Message

This is an open letter to the President of Italy from the EMSC:-

http://www.emsc-csem.org/Doc/Laquila_indictment_EMSC_Suppor= t.pdf

Martin

Subject: Re: J'accuse From: Mauro Mariotti mariotti@......... Date: Sun, 04 Jul 2010 18:06:32 +0200 Hi All, since i am Italian and work on seismology field since 1997 when an earthquake stroke my area (Umbria-Marche) with some causalties also, i hope to provide clarification on what is going on. It would be a very long story to report but i can't explain all in a small email, if someone wants know more simply ask here. First of all it should be taken in account that science world and politics in Italy are very bounded to each other. So very often there are discussion (if not literally legal litigation) among different seismic networks for who have calculated properly this or that earthquake magnitude. One say 4.1 the other 3.9 ... bla bla... Earthquake in l'Aquila stroke 6 april 2009. It has been a mainshock after months and months of increasing magnitude in a very long sequence. Historical seismic records for that area supposed a long sequence with expected magnitude up to 7.0 The area is very active and with very very complex faults systems. What I can say is that Giampaolo Giuliani warned the population there because not only he was knowing the seismological history of the place (that include accurate records since 1500 a.c.). Giuliani warned also because he has a small network of detectors that are not exactly radon-detector but it is a more complex system not completely disclosed but it regards a special measurement of radon in a special lead-camera (not sealed of course) capable of trap only certain istopes, (don't ask me more on this because i don't know the details). This earthquake sequence has been monitored also by me and others of the Italian Experimental Seismic Network that is the same as the PSN only is in Italy. It is well known that one of the most reliable earthquake precursors (if i am correct it should be analyzed by a japanese named Takamori or soemthing like it i don't remember, sorry); that is presente when a sequence of small earthquake rise and rise in magnitude and frequency during time until suddenly the sequence of events stops without have decreased the magnitude. In this case from up to 72 hours you must expect a "mainshock" of magnitude from 1 to 1.5 magnitude over the higher magnitude observed in the foreshocks. This is exactly what happened in l'aquila. So this earthquake could be forecasted. But almost nobody is complaining this specifically. Almost every people in Abruzzo (L'Aquila's region) is complaing that the evening of the 5th april the Civil Defense was going up and down on the villages telling: "Please go back home, inside home. There is no concern, please leave the roads free, there is no alarm for earthquakes." This politic to keep people calm and not induce panic is common custom and fashion since tenths of years in Italy. The main question of the people now is: IF THE EARTHQUAKE CANNOT BE FORECASTED WHAY CIVIL DEFENSE TOLD PEOPLE TO GO INSIDE HOUSES EXPLAINING THAT NO EARTHQUAKE WILL HAPPENS? If there is no way to forecast earthquake you cannot forecast if it will happen NOR if it would NOT happen. And now the people are upset because 300 causualties, among these many young students in the university that called the families telling: do not worry, the civil defense told us there is NO concern. So I remain here because tomorrow i have exams etc. etc... This is what happened in L'Aquila. There is no arrogance among families. Only upset against a corrupted and lobbiest scientific class of people. Technical explaination: The region surrounding l'Aquila is a very strange area sismologically speaking, it is very active in seismic and also present a VERY STRONG effect of site amplification. I write a link of one interesting article wrote by a friend of mine that explain how is the underground near l'aquila and explain why so many damages happened even if recent buildings. You can download the article clicking here: http://www.infoeq.it/LF_AMPLIFICATION_AQUILA.PDF Best regards Mauro Il 04/07/2010 12:13, Tangazazen@....... ha scritto: > > Hi All, > > I do not know if all members are aware of the events unfolding in > Italy. It seems the Italian seismologists are to be prosecute for man > slaughter for failing to predict the earthquake at L'Aquila. This is in spite of > one Giampaolo Giuliani touring the town a week before with a loud speaker > van warning the residents. He was subsequently arrested. > It is times like this that I feel that mankind has been very arrogant to > bestow on himself the title of Homo Sapien. > > > Martin Page > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: J'Accuse From: Mauro Mariotti mariotti@......... Date: Sun, 04 Jul 2010 18:21:57 +0200 Hi again, Thank to Martin to brought it to my attention sinc i have underlooked it, i want to tell you another story regardin 1997. In september 1997 the ceiling of the Assisi church collapsed over some tecnicians and a cameraman of Italian News Tg5 recorded everything, maybe someone remember this: http://www.youtube.com/watch?v=vZ_vR2tDbhg&feature=related Why these tecnician was there after less than 12 hours after one big event? It is well documented and also historically (hudreds of year before) that Appenninian fault systems always release TWO events. Usually the second with 12-20 hours and that it can be near or slightly over the main shock. If you want I can post some extraction of Italian earthquake official catalogues. Please keep present that the faults system northern to city of Terni and southern from Terni have a rather different behaviour and also magnitude over terni historic catalouge report up to 5.0-6.0 magnitudes, below Terni up to 7.8 in magnitude. best regards Mauro Il 04/07/2010 16:51, Tangazazen@....... ha scritto: > > > Thank you Jerry, > I should have made a web reference to this drama but to make amends I > quote the L'Aquila's public prosecutor Alfredo Rossini who recently said, > "Those responsible are people who should have given different answers to the > public. We're not talking about the lack of an alarm, the alarm came with > the movements of the ground. We're talking about the lack of advice telling > people to leave their homes." > > This is an open letter to the President of Italy from the EMSC:- > > _http://www.emsc-csem.org/Doc/Laquila_indictment_EMSC_Support.pdf_ > (http://www.emsc-csem.org/Doc/Laquila_indictment_EMSC_Support.pdf) > > > Martin > > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: J'accuse From: "Stephen Hammond" shammon1@............. Date: Sun, 4 Jul 2010 12:16:49 -0700 Thanks Mauro for your update. If there are other interesting developments in Italy, please post them here to the PSN list. This is a good example of what can happen if you issue / don't issue a warning without really creditable scientific data supporting your conclusions. Here in the USA I feel the USGS has been doing a really good job of handling both the issue of warning the public about the dangers and then following any major event providing information to the public. This is normally done by radio, TV and the Internet. However, in reading your post, what I find different is the folks here at the USGS seem to always include the likelihoods / probabilities of a larger event occurring in their current assessments which allows the public to decide for themselves if they should evacuate to a safer location. The only example of a real prediction within a window of time that I can think of was Al Lynd's USGS in Menlo Park prediction for the Parkfield, CA earthquake. The event did occur but missed the window by about ten years. Al took a lot of heat over this because the had alarmed the town of Parkfield and a lot of money was spent in preparation of a large event. Eventually all the preparation paid-off and the town withstood the earthquake. Please keep us posted, Steve Hammond PSN San Jose-- Aptos, CA USA -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Mauro Mariotti Sent: Sunday, July 04, 2010 9:07 AM To: psn-l@.............. Subject: Re: J'accuse Hi All, since i am Italian and work on seismology field since 1997 when an earthquake stroke my area (Umbria-Marche) with some causalties also, i hope to provide clarification on what is going on. It would be a very long story to report but i can't explain all in a small email, if someone wants know more simply ask here. First of all it should be taken in account that science world and politics in Italy are very bounded to each other. So very often there are discussion (if not literally legal litigation) among different seismic networks for who have calculated properly this or that earthquake magnitude. One say 4.1 the other 3.9 ... bla bla... Earthquake in l'Aquila stroke 6 april 2009. It has been a mainshock after months and months of increasing magnitude in a very long sequence. Historical seismic records for that area supposed a long sequence with expected magnitude up to 7.0 The area is very active and with very very complex faults systems. What I can say is that Giampaolo Giuliani warned the population there because not only he was knowing the seismological history of the place (that include accurate records since 1500 a.c.). Giuliani warned also because he has a small network of detectors that are not exactly radon-detector but it is a more complex system not completely disclosed but it regards a special measurement of radon in a special lead-camera (not sealed of course) capable of trap only certain istopes, (don't ask me more on this because i don't know the details). This earthquake sequence has been monitored also by me and others of the Italian Experimental Seismic Network that is the same as the PSN only is in Italy. It is well known that one of the most reliable earthquake precursors (if i am correct it should be analyzed by a japanese named Takamori or soemthing like it i don't remember, sorry); that is presente when a sequence of small earthquake rise and rise in magnitude and frequency during time until suddenly the sequence of events stops without have decreased the magnitude. In this case from up to 72 hours you must expect a "mainshock" of magnitude from 1 to 1.5 magnitude over the higher magnitude observed in the foreshocks. This is exactly what happened in l'aquila. So this earthquake could be forecasted. But almost nobody is complaining this specifically. Almost every people in Abruzzo (L'Aquila's region) is complaing that the evening of the 5th april the Civil Defense was going up and down on the villages telling: "Please go back home, inside home. There is no concern, please leave the roads free, there is no alarm for earthquakes." This politic to keep people calm and not induce panic is common custom and fashion since tenths of years in Italy. The main question of the people now is: IF THE EARTHQUAKE CANNOT BE FORECASTED WHAY CIVIL DEFENSE TOLD PEOPLE TO GO INSIDE HOUSES EXPLAINING THAT NO EARTHQUAKE WILL HAPPENS? If there is no way to forecast earthquake you cannot forecast if it will happen NOR if it would NOT happen. And now the people are upset because 300 causualties, among these many young students in the university that called the families telling: do not worry, the civil defense told us there is NO concern. So I remain here because tomorrow i have exams etc. etc... This is what happened in L'Aquila. There is no arrogance among families. Only upset against a corrupted and lobbiest scientific class of people. Technical explaination: The region surrounding l'Aquila is a very strange area sismologically speaking, it is very active in seismic and also present a VERY STRONG effect of site amplification. I write a link of one interesting article wrote by a friend of mine that explain how is the underground near l'aquila and explain why so many damages happened even if recent buildings. You can download the article clicking here: http://www.infoeq.it/LF_AMPLIFICATION_AQUILA.PDF Best regards Mauro Il 04/07/2010 12:13, Tangazazen@....... ha scritto: > > Hi All, > > I do not know if all members are aware of the events unfolding in > Italy. It seems the Italian seismologists are to be prosecute for man > slaughter for failing to predict the earthquake at L'Aquila. This is in spite of > one Giampaolo Giuliani touring the town a week before with a loud speaker > van warning the residents. He was subsequently arrested. > It is times like this that I feel that mankind has been very arrogant to > bestow on himself the title of Homo Sapien. > > > Martin Page > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: J'accuse From: "Geoffrey" gmvoeth@........... Date: Sun, 4 Jul 2010 19:18:43 -0700 I have read about the subject of Criminology, The study of all aspects of a criminal justice system. There exists a slight possibility it is not the real reason of his arrest. Law enforcement has been known to arrest and confine people for trumped up charges simply because other more dangerous forces are mustered against this fellow. The only way the law can keep him alive till the heat blows over might be by arresting him and confining him for stupid reasons that aren't really true. Not all of this, may be as it appears and, the forces that be, will not share this concept with you. I hope he is not going to be hung for some natural force that can not realistically be predicted. There's A scientist in Ispra Italy At the JRC, who I hope is watching this. His name too, is Martin. Regards, geoff ----- Original Message ----- From: To: Sent: Sunday, July 04, 2010 3:13 AM Subject: J'accuse > > Hi All, > > I do not know if all members are aware of the events unfolding in > Italy. It seems the Italian seismologists are to be prosecute for man > slaughter for failing to predict the earthquake at L'Aquila. This is in spite of > one Giampaolo Giuliani touring the town a week before with a loud speaker > van warning the residents. He was subsequently arrested. > It is times like this that I feel that mankind has been very arrogant to > bestow on himself the title of Homo Sapien. > > > Martin Page > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: J'accuse From: Mauro Mariotti mariotti@......... Date: Mon, 05 Jul 2010 09:30:11 +0200 Hello, Italy is probably the country with the highest seismic risk in the world. Seismic risk is not related to intenstity of expected earthquakes but it is a result of some factors: frequency, intensity and distribution of expected earthquake multiplied by age of building and the inverse of building robustness. Italy is an old country with many many building that cannot be simply demolished and rebuilt with new tecniques. Churches, castles, country houses belongs to the artistic and historical inheritage that is protected and cannot be modified. Of course popular houses can be modified and rebuilt with modern approaches. Not easy to do before an earthquake, almost nobody apply modifications to houses (getting out money by themselfes). So good public education and proper scientific and civil defense warnings are a key to solve this puzzle. I like what USGS is doing in the last years. Doing this in italy is almost impossible due to politics and crazy people that act like catholic church to Galileo. The opinion I have here after all this events is: 1) Inform clearly people about dangerousness of his area 2) Force proper building regulation 3) Recomend guidelines to be safe inside safe building (fix fornitures and shelf to avoid stuffs falls on your head during a shake) 4) Inform (not warn) population that a shake sequence is in act in a certain area. 5) If the sequence is serious and the historical record tells special care civil defense should make available tents in open spaces where people that are afraid to sleep inside house due to the house ageness can stay at night. Doing this earthquake forecast would become in time like weather forecast. Please don't exchange or overlap the definition "earthquake forecast" with "earthquake prediction". Earthquakes cannot be predicted, but can be forecasted. best regards Mauro Il 04/07/2010 21:16, Stephen Hammond ha scritto: > Thanks Mauro for your update. If there are other interesting developments in > Italy, please post them here to the PSN list. This is a good example of what > can happen if you issue / don't issue a warning without really creditable > scientific data supporting your conclusions. Here in the USA I feel the USGS > has been doing a really good job of handling both the issue of warning the > public about the dangers and then following any major event providing > information to the public. This is normally done by radio, TV and the > Internet. However, in reading your post, what I find different is the folks > here at the USGS seem to always include the likelihoods / probabilities of a > larger event occurring in their current assessments which allows the public > to decide for themselves if they should evacuate to a safer location. The > only example of a real prediction within a window of time that I can think > of was Al Lynd's USGS in Menlo Park prediction for the Parkfield, CA > earthquake. The event did occur but missed the window by about ten years. Al > took a lot of heat over this because the had alarmed the town of Parkfield > and a lot of money was spent in preparation of a large event. Eventually all > the preparation paid-off and the town withstood the earthquake. > > Please keep us posted, Steve Hammond PSN San Jose-- Aptos, CA USA > > -----Original Message----- > From: psn-l-request@.............. [mailto:psn-l-request@............... On > Behalf Of Mauro Mariotti > Sent: Sunday, July 04, 2010 9:07 AM > To: psn-l@.............. > Subject: Re: J'accuse > > Hi All, > since i am Italian and work on seismology field since 1997 when an > earthquake stroke my area (Umbria-Marche) with some causalties also, i > hope to provide clarification on what is going on. > > It would be a very long story to report but i can't explain all in a > small email, if someone wants know more simply ask here. > > First of all it should be taken in account that science world and > politics in Italy are very bounded to each other. So very often there > are discussion (if not literally legal litigation) among different > seismic networks for who have calculated properly this or that > earthquake magnitude. One say 4.1 the other 3.9 ... bla bla... > > Earthquake in l'Aquila stroke 6 april 2009. > It has been a mainshock after months and months of increasing magnitude > in a very long sequence. Historical seismic records for that area > supposed a long sequence with expected magnitude up to 7.0 > > The area is very active and with very very complex faults systems. > > What I can say is that Giampaolo Giuliani warned the population there > because not only he was knowing the seismological history of the place > (that include accurate records since 1500 a.c.). > Giuliani warned also because he has a small network of detectors that > are not exactly radon-detector but it is a more complex system not > completely disclosed but it regards a special measurement of radon in a > special lead-camera (not sealed of course) capable of trap only certain > istopes, (don't ask me more on this because i don't know the details). > > This earthquake sequence has been monitored also by me and others of the > Italian Experimental Seismic Network that is the same as the PSN only is > in Italy. > > It is well known that one of the most reliable earthquake precursors (if > i am correct it should be analyzed by a japanese named Takamori or > soemthing like it i don't remember, sorry); that is presente when a > sequence of small earthquake rise and rise in magnitude and frequency > during time until suddenly the sequence of events stops without have > decreased the magnitude. In this case from up to 72 hours you must > expect a "mainshock" of magnitude from 1 to 1.5 magnitude over the > higher magnitude observed in the foreshocks. > This is exactly what happened in l'aquila. > So this earthquake could be forecasted. > But almost nobody is complaining this specifically. > Almost every people in Abruzzo (L'Aquila's region) is complaing that the > evening of the 5th april the Civil Defense was going up and down on the > villages telling: > "Please go back home, inside home. > There is no concern, please leave the roads free, there is no alarm for > earthquakes." > > This politic to keep people calm and not induce panic is common custom > and fashion since tenths of years in Italy. > > The main question of the people now is: > IF THE EARTHQUAKE CANNOT BE FORECASTED WHAY CIVIL DEFENSE TOLD PEOPLE TO > GO INSIDE HOUSES EXPLAINING THAT NO EARTHQUAKE WILL HAPPENS? > If there is no way to forecast earthquake you cannot forecast if it will > happen NOR if it would NOT happen. > > And now the people are upset because 300 causualties, among these many > young students in the university that called the families telling: do > not worry, the civil defense told us there is NO concern. So I remain > here because tomorrow i have exams etc. etc... > > This is what happened in L'Aquila. > There is no arrogance among families. > Only upset against a corrupted and lobbiest scientific class of people. > > Technical explaination: > The region surrounding l'Aquila is a very strange area sismologically > speaking, it is very active in seismic and also present a VERY STRONG > effect of site amplification. > > I write a link of one interesting article wrote by a friend of mine that > explain how is the underground near l'aquila and explain why so many > damages happened even if recent buildings. > > You can download the article clicking here: > > http://www.infoeq.it/LF_AMPLIFICATION_AQUILA.PDF > > Best regards > Mauro > > > > > > Il 04/07/2010 12:13, Tangazazen@....... ha scritto: >> >> Hi All, >> >> I do not know if all members are aware of the events unfolding in >> Italy. It seems the Italian seismologists are to be prosecute for man >> slaughter for failing to predict the earthquake at L'Aquila. This is in > spite of >> one Giampaolo Giuliani touring the town a week before with a loud > speaker >> van warning the residents. He was subsequently arrested. >> It is times like this that I feel that mankind has been very arrogant to >> bestow on himself the title of Homo Sapien. >> >> >> Martin Page >> > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: J'accuse From: Tangazazen@....... Date: Mon, 5 Jul 2010 05:15:25 EDT Hi Geof, The events unfolding in Italy are reminiscent of the persecution of Galileo Galilei in 1632 for suggesting that the earth might go round the sun. He was shown the instruments of torture to persuade him otherwise. Lets hope things do not go quite that far. Martin
Hi Geof,

The events unfolding in Italy are reminiscent of the persecution of= Galileo=20 Galilei in 1632 for suggesting that the earth might go round the sun. He= was=20 shown the instruments of torture to persuade him otherwise. Lets hope thin= gs do=20 not go quite that far.

Martin
Subject: Re: J'accuse From: Mauro Mariotti mariotti@......... Date: Mon, 05 Jul 2010 12:21:13 +0200 Hi, now someone remembered me what was told from Civil defense to someone in l'Aquila the night from 5th to 6th april 2009: it was literally: "state tranquilli, tornate nelle vostre case e bevetevi un bicchiere di Montepulciano D'Abruzzo!" that translated in english is: "don't worry, go back inside homes and have a glass of Montepulciano D'Abruzzo" (wich is a good red wine). Is this the proper way to protect lifes? No suprise that somebody wants someone else in prison. But PLEASE don't misunderstand, what do this is politic and corrupted science, not the church... (at least in this case). Mauro Il 05/07/2010 11:15, Tangazazen@....... ha scritto: > Hi Geof, > > The events unfolding in Italy are reminiscent of the persecution of Galileo > Galilei in 1632 for suggesting that the earth might go round the sun. He > was shown the instruments of torture to persuade him otherwise. Lets hope > things do not go quite that far. > > Martin > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: J'accuse From: Tangazazen@....... Date: Mon, 5 Jul 2010 07:13:53 EDT Hi, Thanks Mauro, I shall look out for a bottle of ' Montepulciano D'Aruzzo ' in my local off-licence Cin cin or is it Salute, I was never any good at Italian! Martin
Hi,

Thanks Mauro, I shall look out for a bottle of ' Montepu= lciano=20 D'Aruzzo ' in my local off-licence

Cin cin or is it Salute, I was never any good at Italian!

Martin
Subject: Honshu quake 7.4.10 From: Thomas Dick dickthomas01@............. Date: Mon, 05 Jul 2010 08:56:47 -0500 It has been very quiet here in southern Indiana for about four days. When I saw the USGS list of quakes yesterday, I thought I would see a good record. I worked it up and was disappointed so I didn't post it until today after I saw Bob's (Locust Valley). If you look prior to the arrival of the P wave, there is something there in the frequency of .05 hz (in the one min 40 sec prior to P arrival for Honshu) that appears directional. (e.g. the peak is greater on the E-W than on the N-S and is NOT present on the vertical). The Texas posts show a peak on the vertical too. Since this peak is not synchonous with the S wave arrival from Honshu, is it wish to suppose this is another quake since the Texas stations show a peak on the vertical and probably are closer to it? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re :Honshu quake 7.4.10 From: Bob McClure bobmcclure90@......... Date: Mon, 5 Jul 2010 11:09:59 -0400 My horizontal sensors respond to tilts caused by moving around in the rooms above. I believe the wiggle prior to the P-wave is such an artifact. Bob from Locust Valley My horizontal sensors respond to tilts caused by moving around in the rooms above. I believe the wiggle prior to the P-wave is such an artifact.

Bob from Locust Valley Subject: Re: Honshu quake 7.4.10 From: Bob McClure bobmcclure90@......... Date: Mon, 5 Jul 2010 11:05:42 -0400 My horizontal sensors respond to tilts caused by moving around in the rooms above. I believe the wiggle prior to the P-wave is such an artifact. Bob from Locust Valley On Mon, Jul 5, 2010 at 9:56 AM, Thomas Dick wrote: It has been very quiet here in southern Indiana for about four days. When I saw the USGS list of quakes yesterday, I thought I would see a good record. I worked it up and was disappointed so I didn't post it until today after I saw Bob's (Locust Valley). If you look prior to the arrival of the P wave, there is something there in the frequency of .05 hz (in the one min 40 sec prior to P arrival for Honshu) that appears directional. (e.g. the peak is greater on the E-W than on the N-S and is NOT present on the vertical). The Texas posts show a peak on the vertical too. Since this peak is not synchonous with the S wave arrival from Honshu, is it wish to suppose this is another quake since the Texas stations show a peak on the vertical and probably are closer to it? My horizontal sensors respond to tilts caused by moving around in the rooms above. I believe the wiggle prior to the P-wave is such an artifact.

Bob from Locust Valley

On Mon, Jul 5, 2010 at 9:56 AM, Thomas Dick <dickthomas01@.............> wrote:
It has been very quiet here in southern Indiana for about four days. When I saw the USGS list of quakes yesterday, I thought I would see a good record. I worked it up and was disappointed so I didn't post it until today after I saw Bob's (Locust Valley). If you look prior to the arrival of the P wave, there is something there in the frequency of .05 hz (in the one min 40 sec prior to P arrival for Honshu) that appears directional. (e.g. the peak is greater on the E-W than on the N-S and is NOT present on the vertical). The Texas posts show a peak on the vertical too. Since this peak is not synchonous with the S wave arrival from Honshu, is it wish to suppose this is another quake since the Texas stations show a peak on the vertical and probably are closer to it? Subject: I can't find Recent Quakes for N. California from the USGS From: George Bush ke6pxp@....... Date: Mon, 05 Jul 2010 09:11:07 -0700 Hi- I wonder if any other PSN'ers from Northern California are having trouble downloading N. Calif. quake list from USGS in the Winquake program to process quakes? When I go to EVENT REPORT, then NETWORK REPORT one of my selections is http://quake.wr.usgs.gov/recenteqs/Quakes/quakes0.html (N. Cal Events). When I select it, nothing downloads. This quit working about a month ago and I wonder if the N. Cal. service was discontinued or if the address has changed? I would appreciate any thoughts or help. Sorry to bother all of you who are not in this region. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: I can't find Recent Quakes for N. California from the USGS site anymore From: "Keith Payea" kpayea@.............. Date: Mon, 5 Jul 2010 09:18:07 -0700 Hi George: I check the web page to see the maps and lists every morning. About a month ago they changed the format of the web page. Maybe that feature got lost when they did. Editorial comment: The new pages are "prettier", but not as useful. They used to have the map plus the top 30 earthquakes listed on the same page. Now you have a map or a list, but not both together. Keith -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of George Bush Sent: Monday, July 05, 2010 9:11 AM To: psn-l@.............. Subject: I can't find Recent Quakes for N. California from the USGS site anymore Hi- I wonder if any other PSN'ers from Northern California are having trouble downloading N. Calif. quake list from USGS in the Winquake program to process quakes? When I go to EVENT REPORT, then NETWORK REPORT one of my selections is http://quake.wr.usgs.gov/recenteqs/Quakes/quakes0.html (N. Cal Events). When I select it, nothing downloads. This quit working about a month ago and I wonder if the N. Cal. service was discontinued or if the address has changed? I would appreciate any thoughts or help. Sorry to bother all of you who are not in this region. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Re :Honshu quake 7.4.10 From: Thomas Dick dickthomas01@............. Date: Mon, 05 Jul 2010 14:39:44 -0500 Bob McClure wrote: > My horizontal sensors respond to tilts caused by moving around in the > rooms above. I believe the wiggle prior to the P-wave is such an artifact. > > Bob from Locust Valley Yes Bob, your data "seems" to look that way I agree ... e but look at mine ..... a and then .... x and .... v Well, you are right, I can't seem to find it on the professional equipment .... a __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Windows 7 From: Thomas Dick dickthomas01@............. Date: Fri, 09 Jul 2010 14:37:24 -0500 Will there be any problems running present WinSDR and Winquake with Windows 7? __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Windows 7 From: Larry Cochrane lcochrane@.............. Date: Sat, 10 Jul 2010 14:23:28 -0700 Tom, I have not received any reports of problems with either program running on Windows 7. Regards, Larry Cochrane Redwood City, PSN On 7/9/2010 12:37 PM, Thomas Dick wrote: > Will there be any problems running present WinSDR and Winquake with > Windows 7? > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: The New 64 bit pcs From: "Geoffrey" gmvoeth@........... Date: Sun, 11 Jul 2010 13:07:48 -0700 Hello Psn, are any of you able to verify the following: On the new 64 bit machines you need 8GB of ram to get only 1Gb of 64 bit word space ? You also need a motherboard with a capacity of greater than what you want to use. Like if you want to have full use of 8GB your motherboard will have to handle like 12GB or 16Gb or some of your ram like up to 1GB is lost to hardware mapping. You also need a 64 OS like vista 64 or later. Like 8GB plus 1GB video would be 9GB total ??? Like 8GB RAM plus 1GB video Plus whatever is for hardware is quite a bit more than 8GB ?? Does any of this make sense ? So if you want a full 8GB of ram you need to buy a 16GB motherboard ?? Also, DDR3 is the latest greatest RAM ? I had problems recently relating to enough ram and thats what provoked this investigation. It seems to me if you look at prices a full blown machine today is about the same as a full blown machine of yesterday but several times faster ? Regards, geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Windows 7 From: "Stephen Hammond" shammon1@............. Date: Mon, 12 Jul 2010 10:51:43 -0700 I'm running Winquake on a 10-inch Gateway LT2140u (N450 Intel Atom processer) running Windows 7 and it installed and ran just fine. I have not tried installing Winsdr because there are no serial ports, just USB 2.0 ports. I was wondering if anybody has tried using a Winsdr board via a USB to Serial converter? If you have can you post the brand name you selected. Thanks-- Steve Hammond -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Larry Cochrane Sent: Saturday, July 10, 2010 2:23 PM To: psn-l@.............. Subject: Re: Windows 7 Tom, I have not received any reports of problems with either program running on Windows 7. Regards, Larry Cochrane Redwood City, PSN On 7/9/2010 12:37 PM, Thomas Dick wrote: > Will there be any problems running present WinSDR and Winquake with > Windows 7? > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Windows 7 From: Barry Lotz barry_lotz@............. Date: Mon, 12 Jul 2010 11:10:11 -0700 (PDT) Hi Steve=0AI am running Winsdr thru a serial to usb converter currently. Th= e problem is I =0Aam away from home and can't tell you the brand. I think I= went to Frys or Best =0Abuy. I have had some=A0infrequent communication / = no data read error messages show =0Aup in my log file but I can't specify t= he source. =0A=0A=A0Regards=0ABarry=0Ahttp://www.seismicvault.com =0A=0A=0A= =0A=0A________________________________=0AFrom: Stephen Hammond =0ATo: psn-l@...................... Mon, July 12, 2010 10:51:43= AM=0ASubject: RE: Windows 7=0A=0AI'm running Winquake on a 10-inch Gateway= LT2140u (N450 Intel Atom=0Aprocesser) running Windows 7 and it installed a= nd ran just fine. I have not=0Atried installing Winsdr because there are no= serial ports, just USB 2.0=0Aports. I was wondering if anybody has tried u= sing a Winsdr board via a USB=0Ato Serial converter? If you have can you po= st the brand name you selected. =0A=0AThanks-- Steve Hammond=0A=0A-----Orig= inal Message-----=0AFrom: psn-l-request@.............. [mailto:psn-l-reques= t@............... On=0ABehalf Of Larry Cochrane=0ASent: Saturday, July 10, = 2010 2:23 PM=0ATo: psn-l@......................... Re: Windows 7=0A=0ATom,= =0A=0AI have not received any reports of problems with either program runni= ng on=0AWindows 7.=0A=0ARegards,=0ALarry Cochrane=0ARedwood City, PSN=0A=0A= On 7/9/2010 12:37 PM, Thomas Dick wrote:=0A> Will there be any problems run= ning present WinSDR and Winquake with=0A> Windows 7?=0A> __________________= ________________________________________=0A>=0A> Public Seismic Network Mai= ling List (PSN-L)=0A>=0A> To leave this list email PSN-L-REQUEST@SEISMICNET= ..COM with=0A> the body of the message (first line only): unsubscribe=0A> Se= e http://www.seismicnet.com/maillist.html for more information.=0A>=0A_____= _____________________________________________________=0A=0APublic Seismic N= etwork Mailing List (PSN-L)=0A=0ATo leave this list email PSN-L-REQUEST@SEI= SMICNET.COM with =0Athe body of the message (first line only): unsubscribe= =0ASee http://www.seismicnet.com/maillist.html for more information.=0A=0A_= _________________________________________________________=0A=0APublic Seism= ic Network Mailing List (PSN-L)=0A=0ATo leave this list email PSN-L-REQUEST= @.............. with =0Athe body of the message (first line only): unsubscr= ibe=0ASee http://www.seismicnet.com/maillist.html for more information.=0A

=0A
Hi Steve
=0A
I am running Winsd= r thru a serial to usb converter currently. The problem is I am away from h= ome and can't tell you the brand. I think I went to Frys or Best buy. I hav= e had some infrequent communication / no data read error messages show= up in my log file but I can't specify the source.

Regards<= BR>Barry
http://www.seismicvault.com =0A

=0A

= =0A

From: Stephen Hammond <shammon1@.............>=
To: psn-l@.............. m
Sent: Mon, July 12, 20= 10 10:51:43 AM
Subject: = RE: Windows 7

I'm running Winquake on a 10-inch Gateway LT214= 0u (N450 Intel Atom
processer) running Windows 7 and it installed and ra= n just fine. I have not
tried installing Winsdr because there are no ser= ial ports, just USB 2.0
ports. I was wondering if anybody has tried usin= g a Winsdr board via a USB
to Serial converter? If you have can you post= the brand name you selected.

Thanks-- Steve Hammond

-----Or= iginal Message-----
From: psn-l-request@............ com [mailto:psn-l-request@..............] On
Behalf Of Larry = Cochrane
Sent: Saturday, July 10, 2010 2:23 PM
To: psn-l@webtron= ics.com
Subject: Re: Windows 7

Tom,

I have not receive= d any reports of problems with either program running on
Windows 7.
<= BR>Regards,
Larry Cochrane
Redwood City, PSN

On 7/9/2010 12:37= PM, Thomas Dick wrote:
> Will there be any problems running present = WinSDR and Winquake with
> Windows 7?
> _______________________= ___________________________________
>
> Public Seismic Network = Mailing List (PSN-L)
>
> To leave this list email PSN-L-REQUEST@.............. with
> the body of the messa= ge (first line only): unsubscribe
> See http://www.seismicnet.com/maill= ist.html for more information.
>
_________________________________= _________________________

Public Seismic Network Mailing List (PSN-L= )

To leave this list email PSN-L-REQUEST@SEISMI= CNET.COM with
the body of the message (first line only): unsubscrib= e
See http://www.seismicnet.com/maillist.html for more information.

= __________________________________________________________

Public Se= ismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with
the body of the mes= sage (first line only): unsubscribe
See http://ww= w.seismicnet.com/maillist.html for more information.

Subject: RE: Windows 7 From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Mon, 12 Jul 2010 18:15:27 +0000 Hi, I use Windows 2000 with USB serial converter. There are no problem so far for me using that setup. Regards, J=F3n Fr=EDmann. On m=E1n, 2010-07-12 at 10:51 -0700, Stephen Hammond wrote: > I'm running Winquake on a 10-inch Gateway LT2140u (N450 Intel Atom > processer) running Windows 7 and it installed and ran just fine. I have n= ot > tried installing Winsdr because there are no serial ports, just USB 2.0 > ports. I was wondering if anybody has tried using a Winsdr board via a US= B > to Serial converter? If you have can you post the brand name you selected= ..=20 >=20 > Thanks-- Steve Hammond >=20 > -----Original Message----- > From: psn-l-request@.............. [mailto:psn-l-request@............... = On > Behalf Of Larry Cochrane > Sent: Saturday, July 10, 2010 2:23 PM > To: psn-l@.............. > Subject: Re: Windows 7 >=20 > Tom, >=20 > I have not received any reports of problems with either program running o= n > Windows 7. >=20 > Regards, > Larry Cochrane > Redwood City, PSN >=20 > On 7/9/2010 12:37 PM, Thomas Dick wrote: > > Will there be any problems running present WinSDR and Winquake with > > Windows 7? > > __________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email PSN-L-REQUEST@.............. with > > the body of the message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html for more information. > > > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Windows 7 From: Bob McClure bobmcclure90@......... Date: Mon, 12 Jul 2010 16:17:51 -0400 I am now using a new PC, an eMachines EZ1601-01 All-in-One Desktop with Intel=AE Atom=99 N270 Processor ($406 from Amazon). The operating system is Windows XP. My USB-to-serial adaptor was purchased from USBGear, sku no. 765288, price $11.33 plus $5.89 shipping. It contains an FTDI chip. I use a Dataq DI-154 for data acquisition. I have had no problems at all with this setup, and I see no reason why SDR would not work OK as well. There are drivers available for Windows 7 for the adapter. I like the PC because of its low power consumption and conduction/convection coolling (no fan noise)= . It handles both data acquisition and Web surfing very well. Bob =A0 I am now using a new PC, an eMachines EZ1601-01 All-in-One Desktop with= Intel=AE Atom=99 N270 Processor ($406 from Amazon). The operating system i= s Windows XP. My USB-to-serial adaptor was purchased from USBGear, sku no. = 765288, price $11.33 plus $5.89 shipping. It contains an FTDI chip. I use a= Dataq DI-154 for data acquisition. I have had no problems at all with this= setup, and I see no reason why SDR would not work OK as well. There are dr= ivers available for Windows 7 for the adapter. I like the PC because of its= low power consumption and conduction/convection coolling (no fan noise). I= t handles both data acquisition and Web surfing very well.

Bob
Subject: Re: Windows 7 From: Thomas Dick dickthomas01@............. Date: Mon, 12 Jul 2010 19:43:10 -0500 Thanks Larry. I run XP Pro right now on my whole network (five desk models and three laptops). I was wondering, if the earthquake computer should die, would I have any problems using Windows 7 with your programs. I really like my network (and I like your programs even more). All computers talks to each other without problems and I can talk to ithe earthquake computer from any WiFi site. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: RE: Windows 7 From: "Stephen Hammond" shammon1@............. Date: Tue, 13 Jul 2010 00:17:11 -0700 Thanks for the respones. I'll order the USBGear listed below and give it a try. -- Steve -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Bob McClure Sent: Monday, July 12, 2010 1:18 PM To: psn-l Subject: Re: Windows 7 I am now using a new PC, an eMachines EZ1601-01 All-in-One Desktop with IntelR AtomT N270 Processor ($406 from Amazon). The operating system is Windows XP. My USB-to-serial adaptor was purchased from USBGear, sku no. 765288, price $11.33 plus $5.89 shipping. It contains an FTDI chip. I use a Dataq DI-154 for data acquisition. I have had no problems at all with this setup, and I see no reason why SDR would not work OK as well. There are drivers available for Windows 7 for the adapter. I like the PC because of its low power consumption and conduction/convection coolling (no fan noise). It handles both data acquisition and Web surfing very well. Bob Message

Thanks=20 for the respones. I'll order the USBGear listed below and give it a try. = --=20 Steve

-----Original Message-----
From:=20 psn-l-request@.............. [mailto:psn-l-request@............... = On=20 Behalf Of Bob McClure
Sent: Monday, July 12, 2010 1:18=20 PM
To: psn-l
Subject: Re: Windows=20 7

I am now using a new PC, an eMachines = EZ1601-01=20 All-in-One Desktop with Intel® Atom™ N270 Processor ($406 = from Amazon). The=20 operating system is Windows XP. My USB-to-serial adaptor was purchased = from=20 USBGear, sku no. 765288, price $11.33 plus $5.89 shipping. It contains = an FTDI=20 chip. I use a Dataq DI-154 for data acquisition. I have had no = problems at all=20 with this setup, and I see no reason why SDR would not work OK as = well. There=20 are drivers available for Windows 7 for the adapter. I like the PC = because of=20 its low power consumption and conduction/convection coolling (no fan = noise).=20 It handles both data acquisition and Web surfing very=20 well.

Bob

Subject: RE: Windows 7 From: "Stephen Hammond" shammon1@............. Date: Tue, 13 Jul 2010 00:54:27 -0700 I think there may be more than one of use using a home network and several different systems and OS's. In the July 2010 issue of Maximumpc page 67 there is an article on LogMeIn software. LogMeIn offers several free downloads and besides allowing you to login via the Internet to your local computer they also offer network management software that allows you to login and manage any system within your local network via a LAN or the Internet. As I am in the processes of fixing my data collection system (the motorola GPS is no loger working correctly) I'm also going to move to a much faster system and will installing LogMeIn on it. My goal is to be able to manage and restart (re-boot) the seismic system which is located in the garage via the Internet or via the homenetwork. This also includes acces via my wireless. Once the datacollection system time issue is resolved I also plan on building two new long period sensors because the current AT1 and AT2 sensors and just not working correctly after having to reduce the boom length to install them in their current locations. Regards, Steve Hammond PSN San Jose, Aptos, CA -----Original Message----- From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of Thomas Dick Sent: Monday, July 12, 2010 5:43 PM To: psn-l@.............. Subject: Re: Windows 7 Thanks Larry. I run XP Pro right now on my whole network (five desk models and three laptops). I was wondering, if the earthquake computer should die, would I have any problems using Windows 7 with your programs. I really like my network (and I like your programs even more). All computers talks to each other without problems and I can talk to ithe earthquake computer from any WiFi site. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Windows 7 From: Barry Lotz barry_lotz@............. Date: Tue, 13 Jul 2010 03:59:03 -0700 (PDT) Hi Steve=0AI'm currently using Logmein to manage my sensors. Works great. I= f I can be of =0Aany help let me know.=A0My=A0 data acquisition computer is= a 6 watt Fit-PC running =0AXP=A0( USB inputs). It's=A0about 5"x5"x1.5". Th= e only draw back to this earlier =0Aversion is the RAM is hardwired in. I t= hink its 250mb. I=A0am currently running 8 =0Achannels with Winsdr @ 50=A0s= ps. I have a few (3) sensors that have balancing =0Amotors to maintain sens= or position=A0manually. I bought a serial 8=A0ch=A012 bit ADC =0Acard and s= erial switch card from Weeder Technologies. With these and Logmein I =0Acan= =A0monitor and adjust the sensors remotely.=A0I use a virtual switch contro= l =0Apanel=A0=A0which displays voltages (or other units) and=A0buttons to d= irect the =0Amotors. The software is available thru Weeder Technologies. ..= .. works for me. =0AThe newer Fit-PC's come with WiFi and the ability to ins= tall a solid state=A0HD=A0. =0ARam is 2 gb max,=A0I think. When I get back = into town I plan some long over due =0Asensor maintenance. =0A=0ASorry for = the ramble.=0A=A0Regards=0ABarry =0Ahttp://www.seismicvault.com =0A=0A=0A= =0A=0A________________________________=0AFrom: Stephen Hammond =0ATo: psn-l@...................... Tue, July 13, 2010 12:54:27= AM=0ASubject: RE: Windows 7=0A=0AI think there may be more than one of use= using a home network and=0Aseveral different systems and OS's. In the July= 2010 issue of Maximumpc=0Apage 67 there is an article on LogMeIn software.= LogMeIn offers several=0Afree downloads and besides allowing you to login = via the Internet to=0Ayour local computer they also offer network managemen= t software that=0Aallows you to login and manage any system within your loc= al network via=0Aa LAN or the Internet. As I am in the processes of fixing = my data=0Acollection system (the motorola GPS is no loger working correctly= ) I'm=0Aalso going to move to a much faster system and will installing LogM= eIn=0Aon it. My goal is to be able to manage and restart (re-boot) the seis= mic=0Asystem which is located in the garage via the Internet or via the=0Ah= omenetwork. This also includes acces via my wireless. Once the=0Adatacollec= tion system time issue is resolved I also plan on building two=0Anew long p= eriod sensors because the current AT1 and AT2 sensors and just=0Anot workin= g correctly after having to reduce the boom length to install=0Athem in the= ir current locations. =0A=0ARegards, Steve Hammond PSN San Jose, Aptos, CA

=0A

Hi Steve

=0A

I'm currently usin= g Logmein to manage my sensors. Works great. If I can be of any help let me= know. My data acquisition computer is a 6 watt Fit-PC running X= P ( USB inputs). It's about 5"x5"x1.5". The only draw back to thi= s earlier version is the RAM is hardwired in. I think its 250mb. I am = currently running 8 channels with Winsdr @ 50 sps. I have a few (3) se= nsors that have balancing motors to maintain sensor position manually.= I bought a serial 8 ch 12 bit ADC card and serial switch card fr= om Weeder Technologies. With these and Logmein I can monitor and adjus= t the sensors remotely. I use a virtual switch control panel &nbs= p;which displays voltages (or other units) and buttons to direct the m= otors. The software is available thru Weeder Technologies. ... works for me= .. The newer Fit-PC's come with WiFi and the ability to install a solid stat= e HD . Ram is 2 gb max, I think. When I get back into town I plan some long over due sensor maintena= nce.

=0A

Sorry for the ramble.

Regards
Barry http://= www.seismicvault.com =0A

=0A

=0A= From: Stephen Hammond <shammon1@.............>
To: psn-l@..............
Sent: Tue, July 13, 2010 12:54:27 = AM
Subject: RE: Windows = 7

I think there may be more than one of use using a home netw= ork and
several different systems and OS's. In the July 2010 issue of Ma= ximumpc
page 67 there is an article on LogMeIn software. LogMeIn offers = several
free downloads and besides allowing you to login via the Interne= t to
your local computer they also offer network management software tha= t
allows you to login and manage any system within your local network vi= a
a LAN or the Internet. As I am in the processes of fixing my data
c= ollection system (the motorola GPS is no loger working correctly) I'm
al= so going to move to a much faster system and will installing LogMeIn
on it. My goal is to be able to mana= ge and restart (re-boot) the seismic
system which is located in the gara= ge via the Internet or via the
homenetwork. This also includes acces via= my wireless. Once the
datacollection system time issue is resolved I al= so plan on building two
new long period sensors because the current AT1 = and AT2 sensors and just
not working correctly after having to reduce th= e boom length to install
them in their current locations.

Regard= s, Steve Hammond PSN San Jose, Aptos, CA

Subject: Search Question From: "GPayton" gpayton@............. Date: Tue, 13 Jul 2010 17:53:13 -0500 Hi All. How would I search for earthquake history for a given area or spot, specifically Northern Iraq or Eastern Turkey? The EMSC website does seem to help. Thanks, Jerry

Hi All.

How would I search for earthquake history for a given area or spot, = specifically Northern Iraq or Eastern Turkey? The EMSC website = does seem=20 to help.

Thanks,

Jerry

Subject: Re: Search Question From: Barry Lotz barry_lotz@............. Date: Tue, 13 Jul 2010 16:30:45 -0700 (PDT) Jerry=0AYou might try:=A0 http://earthquake.usgs.gov/earthquakes/eqarchives= /epic/=0A=A0Regards=0ABarry=0Ahttp://www.seismicvault.com =0A=0A=0A=0A=0A__= ______________________________=0AFrom: GPayton =0ATo= : PSN Network List =0ASent: Tue, July 13, 2010 3:53:1= 3 PM=0ASubject: Search Question=0A=0A=0AHi All.=0A=0AHow would I search for= earthquake history for a given area or spot, specifically =0ANorthern Iraq= or Eastern Turkey?=A0 The EMSC website does seem to help.=A0 =0A=0A=0AThan= ks,=0AJerry

=0A

Jerry

=0A

You might try: = http://= earthquake.usgs.gov/earthquakes/eqarchives/epic/

Regards=
Barry
http://www.seismicvault.com =0A

=0A

= =0A

=0A

=0AFrom: GPayton <gpayton@.............&g= t;
To: PSN Network List = <PSN-L@..............>
Sent:<= /SPAN> Tue, July 13, 2010 3:53:13 PM
Subject: Search Question

=0A= =0A=0A

Hi All.

=0A

How would I search for = earthquake history for a given area or spot, specifically Northern Iraq or = Eastern Turkey? The EMSC website does seem to help.

=0A

Thanks,

=0A

Jerry

Subject: Velocity Sensor Question ? From: "Geoffrey" gmvoeth@........... Date: Sat, 17 Jul 2010 07:22:35 -0700 Hello PSN folks, Below Is A Velocity Sensor i had sitting in the corner for the past few years which has collected a lot of dust. "Please Excuse the Years of dust and, possibly, life forms present" I believe it to be a proper design for motion along the plane of the faces of the two magnets. The poles are N=>S TOP S=>N Bottom I intend the coil to move vertically in this picture. http://gmvoeth.home.mchsi.com/100_0516.jpg Do any of you know for sure if this is or is not the correct use of magnet and coil as a sensor ? Please explain your response so I "MIGHT" understand. Best regards, geoff __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Velocity Sensor Question ? From: Brett Nordgren brett3nt@............. Date: Sat, 17 Jul 2010 23:49:09 -0400 Geoff. Looks reasonable to me. Based on your photo, see http://bnordgren.org/seismo/magnet1.pdf The voltage in the coil depends on how many wires cut how many magnetic lines how fast. With the magnets arranged as shown, the magnetic lines go from left to right in the top gap and right to left in the bottom gap. And, if the coil wires are going away from you in the top part of the coil, they will be coming towards you in the bottom part. All that means is that as you move the coil up or down, the voltage generated in the wires of the top half of the coil as they cut magnetic lines, will add to the voltage generated in the wires of the bottom half, adding up to give the output voltage proportional to coil velocity you were looking for. Brett At 10:22 AM 7/17/2010, you wrote: >Hello PSN folks, > >Below Is A Velocity Sensor i had sitting >in the corner for the past few years >which has collected a lot of dust. > >"Please Excuse the Years of dust and, possibly, life forms present" > >I believe it to be a proper design >for motion along the plane of the faces >of the two magnets. > >The poles are N=>S TOP > S=>N Bottom > >I intend the coil to move vertically in this picture. > >http://gmvoeth.home.mchsi.com/100_0516.jpg > >Do any of you know for sure if this is >or is not the correct use of magnet and coil >as a sensor ? > >Please explain your response so I "MIGHT" understand. > >Best regards, >geoff > > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: First post From: Andrew Little little.aa@......... Date: Sun, 18 Jul 2010 09:37:41 +0200 Hello psn, This is my first post, and I would like to ask someone to talk me through uploading event data. The Fox island event is still comming through here in France and I would like to try and upload the data. I am using AmaSeis and will open the file in WinQuake, what next? Thanks in advance. Andy. Hello psn,
This is my first post, and I would like to ask someone to tal= k me through uploading event data.
The Fox island event is still comming= through here in France and I would like to try and upload the data. I am u= sing AmaSeis and will open the file in WinQuake, what next? Thanks in advan= ce.
Andy.

Subject: Re: Velocity Sensor Question ? From: "Geoffrey" gmvoeth@........... Date: Sun, 18 Jul 2010 04:30:39 -0700 Hello Mr. Nordgren; The question I have is thus: Is that coil right for the magnets or, Should it be rectangular in shape with the two vertical sides of the rectangle outside the magnetic flux ? I figure I may need like 1206 feet of 36 AWG(B&S) copper enameled wire for a 2100 turns 500 ohm coil ? The 2100 turns are of enamled wire without a heavy coat of enamel. Is 2100 turns enough ? Would it be better if the coil had a copper or iron core ? This would mean a custom coil rectangular instead of circular. I think it may be possible to have two identical coils center tapped in the middle with a single rare earth magnet in the middle between the two coils then you have the right setup for a proper op amp differential circuit. +COIL- NmagnetS +COIL- THE left coil - is connected to right coil + which is then the ground. Left Coil + goes to op amp + and Right coil - goes to op amp - The relative motion is magnet fixed to ground and coil fixed to device. Coil is stable and magnet moves right and left between the coils. Possibly +/- 2mm of range of motion. Each coil having 1050 to 2100 turns custom wound to be exactly the same. "Which I know is not possible." Close enough for civilian work is all I can expect. As you can tell, I'm not very learned on these affairs. Best regards, geoff ----- Original Message ----- From: "Brett Nordgren" To: Sent: Saturday, July 17, 2010 8:49 PM Subject: Re: Velocity Sensor Question ? > Geoff. > > Looks reasonable to me. > > Based on your photo, see http://bnordgren.org/seismo/magnet1.pdf > > The voltage in the coil depends on how many wires cut how many > magnetic lines how fast. > > With the magnets arranged as shown, the magnetic lines go from left > to right in the top gap and right to left in the bottom gap. And, if > the coil wires are going away from you in the top part of the coil, > they will be coming towards you in the bottom part. > > All that means is that as you move the coil up or down, the voltage > generated in the wires of the top half of the coil as they cut > magnetic lines, will add to the voltage generated in the wires of the > bottom half, adding up to give the output voltage proportional to > coil velocity you were looking for. > > Brett > > > > At 10:22 AM 7/17/2010, you wrote: > >>Hello PSN folks, >> >>Below Is A Velocity Sensor i had sitting >>in the corner for the past few years >>which has collected a lot of dust. >> >>"Please Excuse the Years of dust and, possibly, life forms present" >> >>I believe it to be a proper design >>for motion along the plane of the faces >>of the two magnets. >> >>The poles are N=>S TOP >> S=>N Bottom >> >>I intend the coil to move vertically in this picture. >> >>http://gmvoeth.home.mchsi.com/100_0516.jpg >> >>Do any of you know for sure if this is >>or is not the correct use of magnet and coil >>as a sensor ? >> >>Please explain your response so I "MIGHT" understand. >> >>Best regards, >>geoff >> >> >>__________________________________________________________ >> >>Public Seismic Network Mailing List (PSN-L) >> >>To leave this list email PSN-L-REQUEST@.............. with the body >>of the message (first line only): unsubscribe >>See http://www.seismicnet.com/maillist.html for more information. > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: First post From: "Geoffrey" gmvoeth@........... Date: Sun, 18 Jul 2010 05:32:33 -0700 Im not sure but think you need Larry to help you here. The upload is simple, you simply prepare your PSN file by setting the comments and sensor data and stuff then re-save the whole psn file in whatever data form as either a cropped file ( always smaller in size ) There is an event email address you send your PSN files to and if it gets posted right it may send you a reply its UPLOAD OK & Thanks message. You must always keep your email account the same or the server will not accept the attachment. If you mess up your machine and need to reload your OS then make sure you have exported all your email accounts to a safe place because if the attachment does not come from the very same account you originally made you will have to talk to Larry to straighten it out again. It is good and reliable uploads only so long as you use your same email account to send the attachment. Goto the PSN file, right click send to, mail recipient. You must also go up to the header stuff and right click send to: to get your addresses or contacts with the events address. I will not post the server address since Im not sure i should. It is all described at another PSN website i believe. Look up [PSN, Redwood City, events] at www.google.com I believe. Gut Luk Comrade. geoff ----- Original Message ----- From: "Andrew Little" To: Sent: Sunday, July 18, 2010 12:37 AM Subject: First post > Hello psn, > This is my first post, and I would like to ask someone to talk me through > uploading event data. > The Fox island event is still comming through here in France and I would > like to try and upload the data. I am using AmaSeis and will open the file > in WinQuake, what next? Thanks in advance. > Andy. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Velocity Sensor Question ? From: Brett Nordgren brett3nt@............. Date: Sun, 18 Jul 2010 13:57:43 -0400 Hi Geoff, At 07:30 AM 7/18/2010, you wrote: >Hello Mr. Nordgren; > >The question I have is thus: > >Is that coil right for the magnets or, >Should it be rectangular in shape with the >two vertical sides of the rectangle outside the magnetic flux ? Ideally you want your sensor to be linear. If you move the coil at a constant speed over its mechanical range you would like to see a relatively constant voltage out. You can achieve that in two ways. Have the magnet pole faces large enough that all the coil wires stay well within the magnetic region, or alternatively, make them small enough that all the magnetic lines stay within the region filled with coil wires. When you have the edges of the magnetic field moving across the outside or inside edges of the coil, the linearity suffers, though perhaps not enough to worry about too much. >I figure I may need like 1206 feet of 36 AWG(B&S) copper enameled wire >for a 2100 turns 500 ohm coil ? > >The 2100 turns are of enamled wire without a heavy coat of enamel. > >Is 2100 turns enough ? I guess the question would have to be, enough for what? It all depends on how sensitive you plan to make your signal detection circuit--that is, how much amplifier gain do you plan to have and if you are connecting to an A/D device, what is its sensitivity? In general, I would try to start with the smallest wire and the largest number of turns I could easily manage. Coil resistance of several K Ohms wouldn't be unreasonable. The coil Larry sells I believe has 10,000 turns and is 9,000 Ohms. >Would it be better if the coil had a copper or iron core ? Definitely no. Iron would "suck in" the magnetic lines, away from the wires where you want them to be. Copper, unless it made a complete loop, wouldn't do much since it wouldn't be in the magnetic field, certainly nothing particularly helpful. >This would mean a custom coil rectangular instead of circular. Possibly you'd get slightly better linearity with a rectangular coil and rectangular magnet pole pieces, but either shape should work reasonably well for what you are trying to do. >I think it may be possible to have two identical >coils center tapped in the middle with a single >rare earth magnet in the middle between the two >coils then you have the right setup for >a proper op amp differential circuit. I may be wrong, but I am suspecting that you are wanting to connect one output to each of the two inputs of an op amp. If that is what you are thinking about, the problem will be too much gain. Typical op amps have voltage gains of 100's of thousands, or more often, millions. Generally for approximate analyses designers assume that their gain is infinite. That means that extremely tiny input signals (noise) would have the op amp output bouncing between its voltage limits--not very useful. Usually op amps are connected up as single ended amplifiers using a two-resistor feedback circuit, which makes a very nice voltage amplifier. See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure 3. If you do that, one coil will work fine, and by changing the resistor values you can choose the amplifier gain to complement your coil sensitivity. The only advantage I can think of for some kind of differential coil setup is that it might not be as sensitive to 60 Hz hum. Though it probably wouldn't be that hard to connect a differential coil to a single-ended amplifier, sort of like a guitar "hum-bucking" pickup. An instrumentation amplifier *would* allow for independent connections to a pair of coils, but they tend to be a lot more expensive and their gain usually can't be adjusted as precisely. See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure 2. >+COIL- NmagnetS +COIL- > >THE left coil - is connected to right coil + >which is then the ground. > >Left Coil + goes to op amp + >and >Right coil - goes to op amp - > >The relative motion is magnet fixed to ground >and coil fixed to device. > >Coil is stable and magnet moves right and left >between the coils. > >Possibly +/- 2mm of range of motion. > >Each coil having 1050 to 2100 turns >custom wound to be exactly the same. Hope that's a start, Brett __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Velocity Sensor Question ? From: Brett Nordgren brett3nt@............. Date: Sun, 18 Jul 2010 14:57:06 -0400 Hi Geoff, That second reference URL should have been: An instrumentation amplifier *would* allow for independent connections to a pair of coils, but they tend to be a lot more expensive and their gain usually can't be adjusted as precisely. See: http://www.analog.com/static/imported-files/tutorials/MT-061.pdf Figure 2. Sorry, Brett __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: What are the implications of a M2.8 quake near the San Andreas From: George Bush ke6pxp@....... Date: Sun, 18 Jul 2010 14:32:24 -0700 Hello- This morning we had a M2.8 quake about 4 miles west of us out in the ocean and about 5 miles from the San Andreas fault that runs to the East of us. It was on a minor fault that runs parallel to the San Andreas. The shock knocked my data acquisition computer off-line, but was strong enough to jiggle the pen on my drum recorder that also was off line! I am wondering if the movement of the minor fault will add strain or relieve strain on the San Andreas fault (add or decrease the chances of the San Andreas fault letting-go). I would appreciate any thoughts or opinions on this from you PSN folks. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? From: jzambory@......... Date: Sun, 18 Jul 2010 15:49:45 -0600 Look out, that is the start, you guys are about to fall into the ocean!!! ;-) I have no idea... Jeff On 18 Jul 2010 at 14:32, George Bush wrote: > Hello- > > This morning we had a M2.8 quake about 4 miles west of us out in the > ocean and about 5 miles from the San Andreas fault that runs to the > East of us. It was on a minor fault that runs parallel to the San > Andreas. The shock knocked my data acquisition computer off-line, but > was strong enough to jiggle the pen on my drum recorder that also was off line! > > I am wondering if the movement of the minor fault will add strain or > relieve strain on the San Andreas fault (add or decrease the chances > of the San Andreas fault letting-go). > > I would appreciate any thoughts or opinions on this from you PSN folks. > > > George Bush > Sea Ranch, CA, USA > 38.73775N, 123.48882W > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: First post From: Andrew Little little.aa@......... Date: Sun, 18 Jul 2010 23:50:27 +0200 Thanks for the help with the upload, so far so good. Andy. Thanks for the help with the upload, so far so good.
Andy.

Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? From: "GPayton" gpayton@............. Date: Sun, 18 Jul 2010 16:58:02 -0500 Hi George, I will do a flimsy attempt in answering you question. Yesterday, I received the August issue of EARTH magazine with contained a sort article about the Nazca Plate adjacent to Peru. The article was titled Peruvian Plates Move With and Without Earthquakes. If I understood the article correctly, it was asking the question as to why a block of the plate might move seismic and another part generate an earthquake. It pointed out that the majority of the earthquakes occur inland and not actually off shore at the subducting ridge itself. In humble opinion, that may be because of lubrication from the seawater, which would be less and less at the wedge-shaped plated subducted underneath the South American Plate. THAT is strictly a guess on my part, as I have NO technical training in geology or seismology! In regard to your question, I would think the same process "may" be in play there and there may or may not be a direct interaction, who knows. One might think that jostling a already stressed block might cause it to release; and again it might just lessen the stress. I'd be interested in others opinions. Who knows, I might learn something........Naaaaaa. Regards, Jerry -------------------------------------------------------------------------------- ----- Original Message ----- From: George Bush To: psn-l@.............. Sent: Sunday, July 18, 2010 4:32 PM Subject: What are the implications of a M2.8 quake near the San Andreas fault? Hello- This morning we had a M2.8 quake about 4 miles west of us out in the ocean and about 5 miles from the San Andreas fault that runs to the East of us. It was on a minor fault that runs parallel to the San Andreas. The shock knocked my data acquisition computer off-line, but was strong enough to jiggle the pen on my drum recorder that also was off line! I am wondering if the movement of the minor fault will add strain or relieve strain on the San Andreas fault (add or decrease the chances of the San Andreas fault letting-go). I would appreciate any thoughts or opinions on this from you PSN folks. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information.

Hi George,

I will do a flimsy attempt in answering you question. = Yesterday, I=20 received the August issue of EARTH magazine with contained a sort = article=20 about the Nazca Plate adjacent to Peru. The article was titled=20 Peruvian Plates Move With and Without Earthquakes.

If I understood the article correctly, it was asking the question = as to why=20 a block of the plate might move seismic and another part generate an=20 earthquake. It pointed out that the majority of the earthquakes = occur=20 inland and not actually off shore at the subducting ridge itself.

In humble opinion, that may be because of lubrication from the = seawater,=20 which would be less and less at the wedge-shaped plated subducted = underneath the=20 South American Plate. THAT is strictly a guess on my part, as I = have NO=20 technical training in geology or seismology!

In regard to your question, I would think the same process "may" be = in play=20 there and there may or may not be a direct interaction, who knows. = One=20 might think that jostling a already stressed block might cause it to = release;=20 and again it might just lessen the stress.

I'd be interested in others opinions. Who knows, I might = learn=20 something........Naaaaaa.

Regards,

Jerry

----- Original Message -----

From:=20 George = Bush

To: psn-l@..............

Sent: Sunday, July 18, 2010 = 4:32 PM

Subject: What are the = implications of a=20 M2.8 quake near the San Andreas fault?

Hello-

This morning we had a M2.8 quake about 4 = miles=20 west of us out in the
ocean and about 5 miles from the San Andreas = fault=20 that runs to the
East of us. It was on a minor fault that runs = parallel to=20 the San
Andreas. The shock knocked my data acquisition computer = off-line,=20 but
was strong enough to jiggle the pen on my drum recorder that = also was=20 off line!

I am wondering if the movement of the minor fault = will add=20 strain or
relieve strain on the San Andreas fault (add or decrease = the=20 chances
of the San Andreas fault letting-go).

I would = appreciate=20 any thoughts or opinions on this from you PSN folks.

George = Bush
Sea Ranch, CA, USA
38.73775N, 123.48882W=20 =

__________________________________________________________
Public=20 Seismic Network Mailing List (PSN-L)

To leave this list email = PSN-L-REQUEST@............... =20 with
the body of the message (first line only): unsubscribe
See = http://www.seismicnet.co= m/maillist.html=20 for more information.
Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? From: Barry Lotz barry_lotz@............. Date: Sun, 18 Jul 2010 16:15:31 -0700 (PDT) I keep an eye on this site. nice calif activity=A0display=0Ahttp://earthqua= ke.usgs.gov/earthquakes/recenteqsus/Maps/US10/32.42.-125.-115.php=0A=A0Rega= rds=0ABarry=0Ahttp://www.seismicvault.com =0A=0A=0A=0A=0A__________________= ______________=0AFrom: GPayton =0ATo: psn-l@webtroni= cs.com=0ASent: Sun, July 18, 2010 2:58:02 PM=0ASubject: Re: What are the im= plications of a M2.8 quake near the San Andreas =0Afault?=0A=0A=0AHi George= ,=0A=0AI will do a flimsy attempt in answering you question.=A0 Yesterday, = I received the =0AAugust issue of=A0 EARTH magazine with contained a sort a= rticle about the Nazca =0APlate adjacent to Peru.=A0 The article was titled= Peruvian Plates Move With and =0AWithout Earthquakes.=0A=A0=0AIf I underst= ood the article correctly, it was asking the question as to why a =0Ablock = of the plate might move seismic and another part generate an earthquake.=A0= =0AIt pointed out that the majority of the earthquakes occur inland and no= t =0Aactually off shore at the subducting ridge itself.=0A=0AIn humble opin= ion, that may be because of lubrication from the seawater, which =0Awould b= e less and less at the wedge-shaped plated subducted underneath the South = =0AAmerican Plate.=A0 THAT is strictly a guess on my part, as I have NO tec= hnical =0Atraining in geology or seismology!=0A=0AIn regard to your questio= n, I would think the same process "may" be in play =0Athere and there may o= r may not be a direct interaction, who knows.=A0 One might =0Athink that jo= stling a already stressed block might cause it to release; and =0Aagain it = might just lessen the stress.=0A=0AI'd be interested in others opinions.=A0= Who knows, I might learn =0Asomething........Naaaaaa.=0A=0ARegards,=0AJerr= y=0A=0A________________________________=0A=0A----- Original Message ----- = =0A>From: George Bush =0A>To: psn-l@.............. =0A>Sent: Sunday, July 1= 8, 2010 4:32 PM=0A>Subject: What are the implications of a M2.8 quake near = the San Andreas fault?=0A>=0A>Hello-=0A>=0A>This morning we had a M2.8 quak= e about 4 miles west of us out in the =0A>ocean and about 5 miles from the = San Andreas fault that runs to the =0A>East of us. It was on a minor fault = that runs parallel to the San =0A>Andreas. The shock knocked my data acquis= ition computer off-line, but =0A>was strong enough to jiggle the pen on my = drum recorder that also was off line!=0A>=0A>I am wondering if the movement= of the minor fault will add strain or =0A>relieve strain on the San Andrea= s fault (add or decrease the chances =0A>of the San Andreas fault letting-g= o).=0A>=0A>I would appreciate any thoughts or opinions on this from you PSN= folks.=0A>=0A>=0A>George Bush=0A>Sea Ranch, CA, USA=0A>38.73775N, 123.4888= 2W =0A>=0A>__________________________________________________________=0A>= =0A>Public Seismic Network Mailing List (PSN-L)=0A>=0A>To leave this list e= mail PSN-L-REQUEST@.............. with =0A>the body of the message (first l= ine only): unsubscribe=0A>See http://www.seismicnet.com/maillist.html for m= ore information.=0A>

=0A

I keep an eye on this site. nice calif a= ctivity display

=0A

http://earthquake.usgs.= gov/earthquakes/recenteqsus/Maps/US10/32.42.-125.-115.php
Regards
Barry
http://www.seismicvault.com =0A

=0A

=0AFrom: GPayton <gpayton@uspayto= ns.com>
To: psn-l@web= tronics.com
Sent: Sun, J= uly 18, 2010 2:58:02 PM
Subject: Re: What are the implications of a M2.8 quake near the San Andreas= fault?

=0A=0A=0A

Hi George,

=0A

I will do a flimsy attempt in answering you question.&n= bsp; Yesterday, I received the August issue of EARTH magazine with co= ntained a sort article about the Nazca Plate adjacent to Peru. The ar= ticle was titled Peruvian Plates Move With and Without Earthquakes.

=0A

=0A
If I understood the article cor= rectly, it was asking the question as to why a block of the plate might mov= e seismic and another part generate an earthquake. It pointed out tha= t the majority of the earthquakes occur inland and not actually off shore a= t the subducting ridge itself.
=0A

=0A
In humble o= pinion, that may be because of lubrication from the seawater, which would b= e less and less at the wedge-shaped plated subducted underneath the South A= merican Plate. THAT is strictly a guess on my part, as I have NO tech= nical training in geology or seismology!
=0A

=0A
I= n regard to your question, I would think the same process "may" be in play = there and there may or may not be a direct interaction, who knows. On= e might think that jostling a already stressed block might cause it to rele= ase; and again it might just lessen the stress.
=0A

= =0A
I'd be interested in others opinions. Who knows, I might lear= n something........Naaaaaa.
=0A

=0A
Regards,
= =0A
Jerry
=0A
=0A
=0A
=0A
=0A
----- Original = Message -----
=0A
From: George Bush
=0A
To: psn-l@..............
= =0A
Sent: Sunday, July 18, 2010 4:32 = PM
=0A
Subject: What are the imp= lications of a M2.8 quake near the San Andreas fault?
=0A

Hello-

This morning we had a M2.8 quake about 4 miles west of us o= ut in the
ocean and about 5 miles from the San Andreas fault that runs = to the
East of us. It was on a minor fault that runs parallel to the Sa= n
Andreas. The shock knocked my data acquisition computer off-line, but=
was strong enough to jiggle the pen on my drum recorder that also was = off line!

I am wondering if the movement of the minor fault will add= strain or
relieve strain on the San Andreas fault (add or decrease the= chances
of the San Andreas fault letting-go).

I would appreciat= e any thoughts or opinions on this from you PSN folks.

George Bu= sh
Sea Ranch, CA, USA
38.73775N, 123.48882W

_________________= _________________________________________

Public Seismic Network Mai= ling List (PSN-L)

To leave this list email PSN-L-REQUEST@............. OM with
the body of the message (first line only): unsubscribe
S= ee http://www.seismicnet.com/maillist.html for more information.

Subject: Re: Velocity Sensor Question ? From: "Geoffrey" gmvoeth@........... Date: Sun, 18 Jul 2010 16:16:55 -0700 Here is the preamp. I was going to place it right at the geophone. The two exact coils will change in step with temperature to keep a stable DC baseline. Minimal drift. http://gmvoeth.home.mchsi.com/AMP001.jpg Any reason this should not be right ? Will Larry sell only the coils ? I might get two to try my ideas. I looked into getting ten wound but the company was outragious in its (retooling fees) It seems they cant simply do it even tho they wind the things for a living. Thanks for your response. Best Regards, geoff PS: if PSN had a binary news server. we could post any kind of file for people to have/look at ? Could someone create a [alt.binaries.seismic.psn] news group, I understand there is a complex process but the creation is free and almost all ISP have one as part of their service. I have tried to understand the process but like Linux OS I cant understand it. I have tried Linux several times but cant make it functional. Fedora 10 installs OK but I just cant get it to be functional. ----- Original Message ----- From: "Brett Nordgren" To: Sent: Sunday, July 18, 2010 10:57 AM Subject: Re: Velocity Sensor Question ? > Hi Geoff, > > At 07:30 AM 7/18/2010, you wrote: >>Hello Mr. Nordgren; >> >>The question I have is thus: >> >>Is that coil right for the magnets or, >>Should it be rectangular in shape with the >>two vertical sides of the rectangle outside the magnetic flux ? > > Ideally you want your sensor to be linear. If you move the coil at a > constant speed over its mechanical range you would like to see a > relatively constant voltage out. You can achieve that in two > ways. Have the magnet pole faces large enough that all the coil > wires stay well within the magnetic region, or alternatively, make > them small enough that all the magnetic lines stay within the region > filled with coil wires. When you have the edges of the magnetic > field moving across the outside or inside edges of the coil, the > linearity suffers, though perhaps not enough to worry about too much. > >>I figure I may need like 1206 feet of 36 AWG(B&S) copper enameled wire >>for a 2100 turns 500 ohm coil ? >> >>The 2100 turns are of enamled wire without a heavy coat of enamel. >> >>Is 2100 turns enough ? > > I guess the question would have to be, enough for what? It all > depends on how sensitive you plan to make your signal detection > circuit--that is, how much amplifier gain do you plan to have and if > you are connecting to an A/D device, what is its sensitivity? In > general, I would try to start with the smallest wire and the largest > number of turns I could easily manage. Coil resistance of several K > Ohms wouldn't be unreasonable. The coil Larry sells I believe has > 10,000 turns and is 9,000 Ohms. > >>Would it be better if the coil had a copper or iron core ? > > Definitely no. Iron would "suck in" the magnetic lines, away from > the wires where you want them to be. Copper, unless it made a > complete loop, wouldn't do much since it wouldn't be in the magnetic > field, certainly nothing particularly helpful. > >>This would mean a custom coil rectangular instead of circular. > > Possibly you'd get slightly better linearity with a rectangular coil > and rectangular magnet pole pieces, but either shape should work > reasonably well for what you are trying to do. > >>I think it may be possible to have two identical >>coils center tapped in the middle with a single >>rare earth magnet in the middle between the two >>coils then you have the right setup for >>a proper op amp differential circuit. > > I may be wrong, but I am suspecting that you are wanting to connect > one output to each of the two inputs of an op amp. If that is what > you are thinking about, the problem will be too much gain. Typical > op amps have voltage gains of 100's of thousands, or more often, > millions. Generally for approximate analyses designers assume that > their gain is infinite. That means that extremely tiny input signals > (noise) would have the op amp output bouncing between its voltage > limits--not very useful. > > Usually op amps are connected up as single ended amplifiers using a > two-resistor feedback circuit, which makes a very nice voltage amplifier. > > See: > http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure 3. > > If you do that, one coil will work fine, and by changing the resistor > values you can choose the amplifier gain to complement your coil > sensitivity. The only advantage I can think of for some kind of > differential coil setup is that it might not be as sensitive to 60 Hz > hum. Though it probably wouldn't be that hard to connect a > differential coil to a single-ended amplifier, sort of like a guitar > "hum-bucking" pickup. > > An instrumentation amplifier *would* allow for independent > connections to a pair of coils, but they tend to be a lot more > expensive and their gain usually can't be adjusted as precisely. > > See: > http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure 2. > >>+COIL- NmagnetS +COIL- >> >>THE left coil - is connected to right coil + >>which is then the ground. >> >>Left Coil + goes to op amp + >>and >>Right coil - goes to op amp - >> >>The relative motion is magnet fixed to ground >>and coil fixed to device. >> >>Coil is stable and magnet moves right and left >>between the coils. >> >>Possibly +/- 2mm of range of motion. >> >>Each coil having 1050 to 2100 turns >>custom wound to be exactly the same. > > Hope that's a start, > Brett > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? From: "Geoffrey" gmvoeth@........... Date: Sun, 18 Jul 2010 16:30:27 -0700 Hello Mr. Bush; I live 400 miles away to the EAST of LA and the quake in 1994 rattled things all around here. Small quakes below like 5.0 are very common. I would not worry about one small quake. But you can be sure, CA will one day have a big one. They have charts (USGS) at places on the internet which show research into high stress areas and places like San Bernardino area is under great stress now or so they believe. Washington State, Nevada, They find high stresses where faults have not moved in a long time. I suggest you research stress/strain as it relates to causing quakes. Or so I understand. Regards, geoff ----- Original Message ----- From: "George Bush" To: Sent: Sunday, July 18, 2010 2:32 PM Subject: What are the implications of a M2.8 quake near the San Andreas fault? > Hello- > > This morning we had a M2.8 quake about 4 miles west of us out in the > ocean and about 5 miles from the San Andreas fault that runs to the > East of us. It was on a minor fault that runs parallel to the San > Andreas. The shock knocked my data acquisition computer off-line, but > was strong enough to jiggle the pen on my drum recorder that also was off line! > > I am wondering if the movement of the minor fault will add strain or > relieve strain on the San Andreas fault (add or decrease the chances > of the San Andreas fault letting-go). > > I would appreciate any thoughts or opinions on this from you PSN folks. > > > George Bush > Sea Ranch, CA, USA > 38.73775N, 123.48882W > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Velocity Sensor Question ? From: Barry Lotz barry_lotz@............. Date: Sun, 18 Jul 2010 17:21:58 -0700 (PDT) Hi Geoff=0AIf you are measuring velocity not displacement there shouldn't b= e any =0Atemperature affects except maybe the electronics. There =A0was a p= ost awile back =0Awith a link to Ebay=A0for a coil winding gismo for <$20. = I'll see if=A0I can find =0Athe link.=A0=A0Regards=0ABarry=0Ahttp://www.sei= smicvault.com =0A=0A=0A=0A=0A________________________________=0AFrom: Geoff= rey =0ATo: psn-l@...................... Sun, July 18, = 2010 4:16:55 PM=0ASubject: Re: Velocity Sensor Question ?=0A=0AHere is the = preamp.=0AI was going to place it right at the geophone.=0AThe two exact co= ils will change in step=0Awith temperature to keep a stable DC=0Abaseline. = Minimal drift.=0A=0Ahttp://gmvoeth.home.mchsi.com/AMP001.jpg=0A=0AAny reaso= n this should not be right ?=0A=0AWill Larry sell only the coils ?=0AI migh= t get two to try my ideas.=0A=0AI looked into getting ten wound but the com= pany=0Awas outragious in its (retooling fees)=0AIt seems they cant simply d= o it even tho they=0Awind the things for a living.=0A=0AThanks for your res= ponse.=0A=0ABest Regards,=0Ageoff=0A=0APS: if PSN had a binary news server.= =0A=A0 =A0 we could post any kind of file=0A=A0 =A0 for people to have/look= at ?=0A=A0 =A0 Could someone create a [alt.binaries.seismic.psn]=0A=A0 =A0= news group, I understand there is a complex process=0A=A0 =A0 but the crea= tion is free and almost all ISP have=0A=A0 =A0 one as part of their service= .. I have tried to understand=0A=A0 =A0 the process but like Linux OS I cant= understand it.=0A=A0 =A0 I have tried Linux several times but cant make it= functional.=0A=A0 =A0 Fedora 10 installs OK but I just cant get it to be f= unctional.=0A=0A----- Original Message ----- From: "Brett Nordgren" =0ATo: =0ASent: Sunday, July 18, 201= 0 10:57 AM=0ASubject: Re: Velocity Sensor Question ?=0A=0A=0A> Hi Geoff,=0A= > =0A> At 07:30 AM 7/18/2010, you wrote:=0A>> Hello Mr. Nordgren;=0A>> =0A>= > The question I have is thus:=0A>> =0A>> Is that coil right for the magnet= s or,=0A>> Should it be rectangular in shape with the=0A>> two vertical sid= es of the rectangle outside the magnetic flux ?=0A> =0A> Ideally you want y= our sensor to be linear.=A0 If you move the coil at a constant =0A>speed ov= er its mechanical range you would like to see a relatively constant =0A>vol= tage out.=A0 You can achieve that in two ways.=A0 Have the magnet pole face= s =0A>large enough that all the coil wires stay well within the magnetic re= gion, or =0A>alternatively, make them small enough that all the magnetic li= nes stay within =0A>the region filled with coil wires.=A0 When you have the= edges of the magnetic =0A>field moving across the outside or inside edges = of the coil, the linearity =0A>suffers, though perhaps not enough to worry = about too much.=0A> =0A>> I figure I may need like 1206 feet of 36 AWG(B&S)= copper enameled wire=0A>> for a 2100 turns 500 ohm coil ?=0A>> =0A>> The 2= 100 turns are of enamled wire without a heavy coat of enamel.=0A>> =0A>> Is= 2100 turns enough ?=0A> =0A> I guess the question would have to be, enough= for what?=A0 It all depends on how =0A>sensitive you plan to make your sig= nal detection circuit--that is, how much =0A>amplifier gain do you plan to = have and if you are connecting to an A/D device, =0A>what is its sensitivit= y?=A0 In general, I would try to start with the smallest =0A>wire and the l= argest number of turns I could easily manage.=A0 Coil resistance of =0A>sev= eral K Ohms wouldn't be unreasonable.=A0 The coil Larry sells I believe has= =0A>10,000 turns and is 9,000 Ohms.=0A> =0A>> Would it be better if the co= il had a copper or iron core ?=0A> =0A> Definitely no.=A0 Iron would "suck = in" the magnetic lines, away from the wires =0A>where you want them to be.= =A0 Copper, unless it made a complete loop, wouldn't do =0A>much since it w= ouldn't be in the magnetic field, certainly nothing particularly =0A>helpfu= l.=0A> =0A>> This would mean a custom coil rectangular instead of circular.= =0A> =0A> Possibly you'd get slightly better linearity with a rectangular c= oil and =0A>rectangular magnet pole pieces, but either shape should work re= asonably well for =0A>what you are trying to do.=0A> =0A>> I think it may b= e possible to have two identical=0A>> coils center tapped in the middle wit= h a single=0A>> rare earth magnet in the middle between the two=0A>> coils = then you have the right setup for=0A>> a proper op amp differential circuit= ..=0A> =0A> I may be wrong, but I am suspecting that you are wanting to conn= ect one output =0A>to each of the two inputs of an op amp.=A0 If that is wh= at you are thinking about, =0A>the problem will be too much gain.=A0 Typica= l op amps have voltage gains of 100's =0A>of thousands, or more often, mill= ions.=A0 Generally for approximate analyses =0A>designers assume that their= gain is infinite.=A0 That means that extremely tiny =0A>input signals (noi= se) would have the op amp output bouncing between its voltage =0A>limits--n= ot very useful.=0A> =0A> Usually op amps are connected up as single ended a= mplifiers using a =0A>two-resistor feedback circuit, which makes a very nic= e voltage amplifier.=0A> =0A> See: http://www.analog.com/static/imported-fi= les/tutorials/MT-032.pdf=A0 Figure =0A>3.=0A> =0A> If you do that, one coil= will work fine, and by changing the resistor values =0A>you can choose the= amplifier gain to complement your coil sensitivity.=A0 The only =0A>advant= age I can think of for some kind of differential coil setup is that it =0A>= might not be as sensitive to 60 Hz hum.=A0 Though it probably wouldn't be t= hat =0A>hard to connect a differential coil to a single-ended amplifier, so= rt of like a =0A>guitar "hum-bucking" pickup.=0A> =0A> An instrumentation a= mplifier *would* allow for independent connections to a =0A>pair of coils, = but they tend to be a lot more expensive and their gain usually =0A>can't b= e adjusted as precisely.=0A> =0A> See: http://www.analog.com/static/importe= d-files/tutorials/MT-032.pdf=A0 Figure =0A>2.=0A> =0A>> +COIL-=A0 NmagnetS = +COIL-=0A>> =0A>> THE left coil - is connected to right coil +=0A>> which i= s then the ground.=0A>> =0A>> Left Coil + goes to op amp +=0A>> and=0A>> Ri= ght coil - goes to op amp -=0A>> =0A>> The relative motion is magnet fixed = to ground=0A>> and coil fixed to device.=0A>> =0A>> Coil is stable and magn= et moves right and left=0A>> between the coils.=0A>> =0A>> Possibly +/- 2mm= of range of motion.=0A>> =0A>> Each coil having 1050 to 2100 turns=0A>> cu= stom wound to be exactly the same.=0A> =0A> Hope that's a start,=0A> Brett= =0A> =0A> =0A> =0A> _______________________________________________________= ___=0A> =0A> Public Seismic Network Mailing List (PSN-L)=0A> =0A> To leave = this list email PSN-L-REQUEST@.............. with the body of the =0A>messa= ge (first line only): unsubscribe=0A> See http://www.seismicnet.com/maillis= t.html for more information.=0A> =0A_______________________________________= ___________________=0A=0APublic Seismic Network Mailing List (PSN-L)=0A=0AT= o leave this list email PSN-L-REQUEST@.............. with the body of the = =0Amessage (first line only): unsubscribe=0ASee http://www.seismicnet.com/m= aillist.html for more information.=0A
=0A
Hi Geoff
=0A
If you are measuri= ng velocity not displacement there shouldn't be any temperature affects exc= ept maybe the electronics. There was a post awile back with a link to= Ebay for a coil winding gismo for <$20. I'll see if I can fin= d the link.
Regards
Barry
http://www.seismicvault.com = =0A

=0A

=0A
=0A
=0AFrom: Geoffrey &l= t;gmvoeth@...........>
To: psn-l@..............
Sent: Sun, July 18, 2010 4:16:55 PM
Subject: Re: Velocity Sensor Question ?

Here i= s the preamp.
I was going to place it right at the geophone.
The two = exact coils will change in step
with temperature to keep a stable DC
= baseline. Minimal drift.

http://gmvoeth.home.mchsi.com/AMP001.jpg
Any reason this should not be right ?

Will Larry sell only the = coils ?
I might get two to try my ideas.

I looked into getting te= n wound but the company
was outragious in its (retooling fees)
It see= ms they cant simply do it even tho they
wind the things for a living.
Thanks for your response.

Best Regards,
geoff

PS: if = PSN had a binary news server.
we could post any kind of file
&nb= sp; for people to have/look at ?
Could someone crea= te a [alt.binaries.seismic.psn]
news group, I understand t= here is a complex process
but the creation is free and alm= ost all ISP have
one as part of their service. I have trie= d to understand
the process but like Linux OS I cant under= stand it.
I have tried Linux several times but cant make i= t functional.
Fedora 10 installs OK but I just cant get it= to be functional.

----- Original Message ----- From: "Brett Nordgre= n" <brett3nt@.............>
To: <psn-l@webtro= nics.com>
Sent: Sunday, July 18, 2010 10:57 AM
Subject: Re: Velocity Sensor Question ?

> Hi Geoff,
>
> At 0= 7:30 AM 7/18/2010, you wrote:
>> Hello Mr. Nordgren;
>> <= BR>>> The question I have is thus:
>>
>> Is that c= oil right for the magnets or,
>> Should it be rectangular in shape= with the
>> two vertical sides of the rectangle outside the magne= tic flux ?
>
> Ideally you want your sensor to be linear. = ; If you move the coil at a constant speed over its mechanical range you wo= uld like to see a relatively constant voltage out. You can achieve th= at in two ways. Have the magnet pole faces large enough that all the = coil wires stay well within the magnetic region, or alternatively, make the= m small enough that all the magnetic lines stay within the region filled wi= th coil wires. When you have the edges of the magnetic field moving a= cross the outside or inside edges of the coil, the linearity suffers, though perhaps not enough to worry about too much.
>
&g= t;> I figure I may need like 1206 feet of 36 AWG(B&S) copper enamele= d wire
>> for a 2100 turns 500 ohm coil ?
>>
>>= The 2100 turns are of enamled wire without a heavy coat of enamel.
>= >
>> Is 2100 turns enough ?
>
> I guess the quest= ion would have to be, enough for what? It all depends on how sensitiv= e you plan to make your signal detection circuit--that is, how much amplifi= er gain do you plan to have and if you are connecting to an A/D device, wha= t is its sensitivity? In general, I would try to start with the small= est wire and the largest number of turns I could easily manage. Coil = resistance of several K Ohms wouldn't be unreasonable. The coil Larry= sells I believe has 10,000 turns and is 9,000 Ohms.
>
>> W= ould it be better if the coil had a copper or iron core ?
>
> Definitely no. Iron would "suck in" the magnetic lines, awa= y from the wires where you want them to be. Copper, unless it made a = complete loop, wouldn't do much since it wouldn't be in the magnetic field,= certainly nothing particularly helpful.
>
>> This would me= an a custom coil rectangular instead of circular.
>
> Possibly= you'd get slightly better linearity with a rectangular coil and rectangula= r magnet pole pieces, but either shape should work reasonably well for what= you are trying to do.
>
>> I think it may be possible to h= ave two identical
>> coils center tapped in the middle with a sing= le
>> rare earth magnet in the middle between the two
>> = coils then you have the right setup for
>> a proper op amp differe= ntial circuit.
>
> I may be wrong, but I am suspecting that yo= u are wanting to connect one output to each of the two inputs of an op amp. If that is what you are thinking about, the problem will be = too much gain. Typical op amps have voltage gains of 100's of thousan= ds, or more often, millions. Generally for approximate analyses desig= ners assume that their gain is infinite. That means that extremely ti= ny input signals (noise) would have the op amp output bouncing between its = voltage limits--not very useful.
>
> Usually op amps are conne= cted up as single ended amplifiers using a two-resistor feedback circuit, w= hich makes a very nice voltage amplifier.
>
> See: http://www.= analog.com/static/imported-files/tutorials/MT-032.pdf Figure 3.
&g= t;
> If you do that, one coil will work fine, and by changing the re= sistor values you can choose the amplifier gain to complement your coil sen= sitivity. The only advantage I can think of for some kind of differen= tial coil setup is that it might not be as sensitive to 60 Hz hum. Though it probably wouldn't be that hard to connect a different= ial coil to a single-ended amplifier, sort of like a guitar "hum-bucking" p= ickup.
>
> An instrumentation amplifier *would* allow for inde= pendent connections to a pair of coils, but they tend to be a lot more expe= nsive and their gain usually can't be adjusted as precisely.
>
&g= t; See: http://www.analog.com/static/imported-files/tutor= ials/MT-032.pdf Figure 2.
>
>> +COIL- Nmagn= etS +COIL-
>>
>> THE left coil - is connected to right c= oil +
>> which is then the ground.
>>
>> Left C= oil + goes to op amp +
>> and
>> Right coil - goes to op = amp -
>>
>> The relative motion is magnet fixed to groun= d
>> and coil fixed to device.
>>
>> Coil is stable and magnet moves right and left
>> between the coils.
&= gt;>
>> Possibly +/- 2mm of range of motion.
>>
&= gt;> Each coil having 1050 to 2100 turns
>> custom wound to be = exactly the same.
>
> Hope that's a start,
> Brett
&g= t;
>
>
> _____________________________________________= _____________
>
> Public Seismic Network Mailing List (PSN-L)<= BR>>
> To leave this list email PSN-L-REQUES= T@.............. with the body of the message (first line only): unsubs= cribe
> See http://www.seismicnet.com/maillist.html for more informat= ion.
>
__________________________________________________________=

Public Seismic Network Mailing List (PSN-L)

To leave this li= st email PSN-L-REQUEST@............. OM with the body of the message (first line only): unsubscribe
See <= A href=3D"http://www.seismicnet.com/maillist.html" target=3D_blank>http://w= ww.seismicnet.com/maillist.html for more information.
Subject: Re: Velocity Sensor Question ? From: Barry Lotz barry_lotz@............. Date: Sun, 18 Jul 2010 17:30:46 -0700 (PDT) Geoff=0A=A0I guess they were a little more expensive than=A0I remembered.= =0Ahttp://http://cgi.ebay.com/Manual-Coil-Winder-Power-Transformer-Winding-= Machine-DI-/360279979429?cmd=3DViewItem&pt=3DLH_DefaultDomain_2&hash=3Ditem= 53e25c35a5=0A=0A=A0Regards=0ABarry=0Ahttp://www.seismicvault.com =0A=0A=0A= =0A=0A________________________________=0AFrom: Geoffrey =0ATo: psn-l@...................... Sun, July 18, 2010 4:16:55 PM=0ASubje= ct: Re: Velocity Sensor Question ?=0A=0AHere is the preamp.=0AI was going t= o place it right at the geophone.=0AThe two exact coils will change in step= =0Awith temperature to keep a stable DC=0Abaseline. Minimal drift.=0A=0Ahtt= p://gmvoeth.home.mchsi.com/AMP001.jpg=0A=0AAny reason this should not be ri= ght ?=0A=0AWill Larry sell only the coils ?=0AI might get two to try my ide= as.=0A=0AI looked into getting ten wound but the company=0Awas outragious i= n its (retooling fees)=0AIt seems they cant simply do it even tho they=0Awi= nd the things for a living.=0A=0AThanks for your response.=0A=0ABest Regard= s,=0Ageoff=0A=0APS: if PSN had a binary news server.=0A=A0 =A0 we could pos= t any kind of file=0A=A0 =A0 for people to have/look at ?=0A=A0 =A0 Could s= omeone create a [alt.binaries.seismic.psn]=0A=A0 =A0 news group, I understa= nd there is a complex process=0A=A0 =A0 but the creation is free and almost= all ISP have=0A=A0 =A0 one as part of their service. I have tried to under= stand=0A=A0 =A0 the process but like Linux OS I cant understand it.=0A=A0 = =A0 I have tried Linux several times but cant make it functional.=0A=A0 =A0= Fedora 10 installs OK but I just cant get it to be functional.=0A=0A----- = Original Message ----- From: "Brett Nordgren" =0ATo= : =0ASent: Sunday, July 18, 2010 10:57 AM=0ASubject: = Re: Velocity Sensor Question ?=0A=0A=0A> Hi Geoff,=0A> =0A> At 07:30 AM 7/1= 8/2010, you wrote:=0A>> Hello Mr. Nordgren;=0A>> =0A>> The question I have = is thus:=0A>> =0A>> Is that coil right for the magnets or,=0A>> Should it b= e rectangular in shape with the=0A>> two vertical sides of the rectangle ou= tside the magnetic flux ?=0A> =0A> Ideally you want your sensor to be linea= r.=A0 If you move the coil at a constant =0A>speed over its mechanical rang= e you would like to see a relatively constant =0A>voltage out.=A0 You can a= chieve that in two ways.=A0 Have the magnet pole faces =0A>large enough tha= t all the coil wires stay well within the magnetic region, or =0A>alternati= vely, make them small enough that all the magnetic lines stay within =0A>th= e region filled with coil wires.=A0 When you have the edges of the magnetic= =0A>field moving across the outside or inside edges of the coil, the linea= rity =0A>suffers, though perhaps not enough to worry about too much.=0A> = =0A>> I figure I may need like 1206 feet of 36 AWG(B&S) copper enameled wir= e=0A>> for a 2100 turns 500 ohm coil ?=0A>> =0A>> The 2100 turns are of ena= mled wire without a heavy coat of enamel.=0A>> =0A>> Is 2100 turns enough ?= =0A> =0A> I guess the question would have to be, enough for what?=A0 It all= depends on how =0A>sensitive you plan to make your signal detection circui= t--that is, how much =0A>amplifier gain do you plan to have and if you are = connecting to an A/D device, =0A>what is its sensitivity?=A0 In general, I = would try to start with the smallest =0A>wire and the largest number of tur= ns I could easily manage.=A0 Coil resistance of =0A>several K Ohms wouldn't= be unreasonable.=A0 The coil Larry sells I believe has =0A>10,000 turns an= d is 9,000 Ohms.=0A> =0A>> Would it be better if the coil had a copper or i= ron core ?=0A> =0A> Definitely no.=A0 Iron would "suck in" the magnetic lin= es, away from the wires =0A>where you want them to be.=A0 Copper, unless it= made a complete loop, wouldn't do =0A>much since it wouldn't be in the mag= netic field, certainly nothing particularly =0A>helpful.=0A> =0A>> This wou= ld mean a custom coil rectangular instead of circular.=0A> =0A> Possibly yo= u'd get slightly better linearity with a rectangular coil and =0A>rectangul= ar magnet pole pieces, but either shape should work reasonably well for =0A= >what you are trying to do.=0A> =0A>> I think it may be possible to have tw= o identical=0A>> coils center tapped in the middle with a single=0A>> rare = earth magnet in the middle between the two=0A>> coils then you have the rig= ht setup for=0A>> a proper op amp differential circuit.=0A> =0A> I may be w= rong, but I am suspecting that you are wanting to connect one output =0A>to= each of the two inputs of an op amp.=A0 If that is what you are thinking a= bout, =0A>the problem will be too much gain.=A0 Typical op amps have voltag= e gains of 100's =0A>of thousands, or more often, millions.=A0 Generally fo= r approximate analyses =0A>designers assume that their gain is infinite.=A0= That means that extremely tiny =0A>input signals (noise) would have the op= amp output bouncing between its voltage =0A>limits--not very useful.=0A> = =0A> Usually op amps are connected up as single ended amplifiers using a = =0A>two-resistor feedback circuit, which makes a very nice voltage amplifie= r.=0A> =0A> See: http://www.analog.com/static/imported-files/tutorials/MT-0= 32.pdf=A0 Figure =0A>3.=0A> =0A> If you do that, one coil will work fine, a= nd by changing the resistor values =0A>you can choose the amplifier gain to= complement your coil sensitivity.=A0 The only =0A>advantage I can think of= for some kind of differential coil setup is that it =0A>might not be as se= nsitive to 60 Hz hum.=A0 Though it probably wouldn't be that =0A>hard to co= nnect a differential coil to a single-ended amplifier, sort of like a =0A>g= uitar "hum-bucking" pickup.=0A> =0A> An instrumentation amplifier *would* a= llow for independent connections to a =0A>pair of coils, but they tend to b= e a lot more expensive and their gain usually =0A>can't be adjusted as prec= isely.=0A> =0A> See: http://www.analog.com/static/imported-files/tutorials/= MT-032.pdf=A0 Figure =0A>2.=0A> =0A>> +COIL-=A0 NmagnetS +COIL-=0A>> =0A>> = THE left coil - is connected to right coil +=0A>> which is then the ground.= =0A>> =0A>> Left Coil + goes to op amp +=0A>> and=0A>> Right coil - goes to= op amp -=0A>> =0A>> The relative motion is magnet fixed to ground=0A>> and= coil fixed to device.=0A>> =0A>> Coil is stable and magnet moves right and= left=0A>> between the coils.=0A>> =0A>> Possibly +/- 2mm of range of motio= n.=0A>> =0A>> Each coil having 1050 to 2100 turns=0A>> custom wound to be e= xactly the same.=0A> =0A> Hope that's a start,=0A> Brett=0A> =0A> =0A> =0A>= __________________________________________________________=0A> =0A> Public= Seismic Network Mailing List (PSN-L)=0A> =0A> To leave this list email PSN= -L-REQUEST@.............. with the body of the =0A>message (first line only= ): unsubscribe=0A> See http://www.seismicnet.com/maillist.html for more inf= ormation.=0A> =0A__________________________________________________________= =0A=0APublic Seismic Network Mailing List (PSN-L)=0A=0ATo leave this list e= mail PSN-L-REQUEST@.............. with the body of the =0Amessage (first li= ne only): unsubscribe=0ASee http://www.seismicnet.com/maillist.html for mor= e information.=0A
=0A
Geoff
=0A
I guess they we= re a little more expensive than I remembered.
=0A
http://http://cgi.ebay.com/Manual-Coil-Winder-Power-Tran= sformer-Winding-Machine-DI-/360279979429?cmd=3DViewItem&pt=3DLH_Default= Domain_2&hash=3Ditem53e25c35a5

Regards
Barry
<= SPAN style=3D"COLOR: rgb(64,64,255); TEXT-DECORATION: underline">http://www= ..seismicvault.com =0A

=0A

=0A
=0A
=0A= From: Geoffrey <gmvoeth@...........>
To: psn-l@..............
Sent: Sun, July 18, 2010 4:16:55 PM
Subject: Re: Velocity Sensor Que= stion ?

Here is the preamp.
I was going to place it right = at the geophone.
The two exact coils will change in step
with tempera= ture to keep a stable DC
baseline. Minimal drift.

http://gmvoeth.= home.mchsi.com/AMP001.jpg

Any reason this should not be right ?
<= BR>Will Larry sell only the coils ?
I might get two to try my ideas.
=
I looked into getting ten wound but the company
was outragious in it= s (retooling fees)
It seems they cant simply do it even tho they
wind= the things for a living.

Thanks for your response.

Best Rega= rds,
geoff

PS: if PSN had a binary news server.
we could post any kind of file
&nb= sp; for people to have/look at ?
Could someone crea= te a [alt.binaries.seismic.psn]
news group, I understand t= here is a complex process
but the creation is free and alm= ost all ISP have
one as part of their service. I have trie= d to understand
the process but like Linux OS I cant under= stand it.
I have tried Linux several times but cant make i= t functional.
Fedora 10 installs OK but I just cant get it= to be functional.

----- Original Message ----- From: "Brett Nordgre= n" <brett3nt@.............>
To: <psn-l@webtro= nics.com>
Sent: Sunday, July 18, 2010 10:57 AM
Subject: Re: Velocity Sensor Question ?

> Hi Geoff,
>
> At 0= 7:30 AM 7/18/2010, you wrote:
>> Hello Mr. Nordgren;
>> <= BR>>> The question I have is thus:
>>
>> Is that c= oil right for the magnets or,
>> Should it be rectangular in shape= with the
>> two vertical sides of the rectangle outside the magne= tic flux ?
>
> Ideally you want your sensor to be linear. = ; If you move the coil at a constant speed over its mechanical range you wo= uld like to see a relatively constant voltage out. You can achieve th= at in two ways. Have the magnet pole faces large enough that all the = coil wires stay well within the magnetic region, or alternatively, make the= m small enough that all the magnetic lines stay within the region filled wi= th coil wires. When you have the edges of the magnetic field moving a= cross the outside or inside edges of the coil, the linearity suffers, though perhaps not enough to worry about too much.
>
&g= t;> I figure I may need like 1206 feet of 36 AWG(B&S) copper enamele= d wire
>> for a 2100 turns 500 ohm coil ?
>>
>>= The 2100 turns are of enamled wire without a heavy coat of enamel.
>= >
>> Is 2100 turns enough ?
>
> I guess the quest= ion would have to be, enough for what? It all depends on how sensitiv= e you plan to make your signal detection circuit--that is, how much amplifi= er gain do you plan to have and if you are connecting to an A/D device, wha= t is its sensitivity? In general, I would try to start with the small= est wire and the largest number of turns I could easily manage. Coil = resistance of several K Ohms wouldn't be unreasonable. The coil Larry= sells I believe has 10,000 turns and is 9,000 Ohms.
>
>> W= ould it be better if the coil had a copper or iron core ?
>
> Definitely no. Iron would "suck in" the magnetic lines, awa= y from the wires where you want them to be. Copper, unless it made a = complete loop, wouldn't do much since it wouldn't be in the magnetic field,= certainly nothing particularly helpful.
>
>> This would me= an a custom coil rectangular instead of circular.
>
> Possibly= you'd get slightly better linearity with a rectangular coil and rectangula= r magnet pole pieces, but either shape should work reasonably well for what= you are trying to do.
>
>> I think it may be possible to h= ave two identical
>> coils center tapped in the middle with a sing= le
>> rare earth magnet in the middle between the two
>> = coils then you have the right setup for
>> a proper op amp differe= ntial circuit.
>
> I may be wrong, but I am suspecting that yo= u are wanting to connect one output to each of the two inputs of an op amp. If that is what you are thinking about, the problem will be = too much gain. Typical op amps have voltage gains of 100's of thousan= ds, or more often, millions. Generally for approximate analyses desig= ners assume that their gain is infinite. That means that extremely ti= ny input signals (noise) would have the op amp output bouncing between its = voltage limits--not very useful.
>
> Usually op amps are conne= cted up as single ended amplifiers using a two-resistor feedback circuit, w= hich makes a very nice voltage amplifier.
>
> See: http://www.= analog.com/static/imported-files/tutorials/MT-032.pdf Figure 3.
&g= t;
> If you do that, one coil will work fine, and by changing the re= sistor values you can choose the amplifier gain to complement your coil sen= sitivity. The only advantage I can think of for some kind of differen= tial coil setup is that it might not be as sensitive to 60 Hz hum. Though it probably wouldn't be that hard to connect a different= ial coil to a single-ended amplifier, sort of like a guitar "hum-bucking" p= ickup.
>
> An instrumentation amplifier *would* allow for inde= pendent connections to a pair of coils, but they tend to be a lot more expe= nsive and their gain usually can't be adjusted as precisely.
>
&g= t; See: http://www.analog.com/static/imported-files/tutor= ials/MT-032.pdf Figure 2.
>
>> +COIL- Nmagn= etS +COIL-
>>
>> THE left coil - is connected to right c= oil +
>> which is then the ground.
>>
>> Left C= oil + goes to op amp +
>> and
>> Right coil - goes to op = amp -
>>
>> The relative motion is magnet fixed to groun= d
>> and coil fixed to device.
>>
>> Coil is stable and magnet moves right and left
>> between the coils.
&= gt;>
>> Possibly +/- 2mm of range of motion.
>>
&= gt;> Each coil having 1050 to 2100 turns
>> custom wound to be = exactly the same.
>
> Hope that's a start,
> Brett
&g= t;
>
>
> _____________________________________________= _____________
>
> Public Seismic Network Mailing List (PSN-L)<= BR>>
> To leave this list email PSN-L-REQUES= T@.............. with the body of the message (first line only): unsubs= cribe
> See http://www.seismicnet.com/maillist.html for more informat= ion.
>
__________________________________________________________=

Public Seismic Network Mailing List (PSN-L)

To leave this li= st email PSN-L-REQUEST@............. OM with the body of the message (first line only): unsubscribe
See <= A href=3D"http://www.seismicnet.com/maillist.html" target=3D_blank>http://w= ww.seismicnet.com/maillist.html for more information.
Subject: Re: What are the implications of a M2.8 quake near the San Andreas From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@......... Date: Mon, 19 Jul 2010 00:56:27 +0000 Hi, It might be a pre-earthquake to a larger earthquake. But only time is going to tell you that. But I wonder why this small earthquake did manage to take your system offline. I try to build my setup in that way that they can at least withstand Mw6.5 earthquake. Regards, J=F3n Fr=EDmann. On sun, 2010-07-18 at 14:32 -0700, George Bush wrote: > Hello- >=20 > This morning we had a M2.8 quake about 4 miles west of us out in the=20 > ocean and about 5 miles from the San Andreas fault that runs to the=20 > East of us. It was on a minor fault that runs parallel to the San=20 > Andreas. The shock knocked my data acquisition computer off-line, but=20 > was strong enough to jiggle the pen on my drum recorder that also was off= line! >=20 > I am wondering if the movement of the minor fault will add strain or=20 > relieve strain on the San Andreas fault (add or decrease the chances=20 > of the San Andreas fault letting-go). >=20 > I would appreciate any thoughts or opinions on this from you PSN folks. >=20 >=20 > George Bush > Sea Ranch, CA, USA > 38.73775N, 123.48882W=20 >=20 > __________________________________________________________ >=20 > Public Seismic Network Mailing List (PSN-L) >=20 > To leave this list email PSN-L-REQUEST@.............. with=20 > the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San Andreas From: Mauro Mariotti mariotti@......... Date: Mon, 19 Jul 2010 09:14:58 +0200 Hello, from far Italy i guess sharing some experience we have here may be useful. Single, spot event usually don't lead to any precursor. Look to event sequences instead. Check for sequence of earthquakes, they have to belong to the same fault system and/or be focused on a constrained area (which can be also rather large, this depends on the seismogenetic structures). Usually dangerous eq sequences follows the seismo structure you have. Check then on the historical records of that area for as back in time you can go and try to see time related patterns. Often the huge ground blocks push to each other and a fault depend on the other, for sure you can find lot of literature about it for your area. Then draw a chart of magnitude of earthquake (Y axis) and time (X axis) and see if magnitude and frequency increase or decrease. Pay much attention if frequency and magnitude stops suddenly. If eq sequence go up in frequency and magnitude, stay in alert. If eq sequence go slowily down in freq. and magnit. probably is only an ew swarm that will exaust with no damages. best regards Mauro Il 18/07/2010 23:32, George Bush ha scritto: > Hello- > > This morning we had a M2.8 quake about 4 miles west of us out in the > ocean and about 5 miles from the San Andreas fault that runs to the East > of us. It was on a minor fault that runs parallel to the San Andreas. > The shock knocked my data acquisition computer off-line, but was strong > enough to jiggle the pen on my drum recorder that also was off line! > > I am wondering if the movement of the minor fault will add strain or > relieve strain on the San Andreas fault (add or decrease the chances of > the San Andreas fault letting-go). > > I would appreciate any thoughts or opinions on this from you PSN folks. > > > George Bush > Sea Ranch, CA, USA > 38.73775N, 123.48882W > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of > the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Velocity Sensor Question From: "Edward Ianni" edwianni1@........... Date: Mon, 19 Jul 2010 12:49:38 +0000 Barry/Geoff On the website instructables.com there are a number of crude = homemade coil winders. Just type in coil winder. Ed.
Barry/Geoff

       On = the website=20 instructables.com there are a number of crude homemade coil = winders.=20 Just type in coil winder.

Ed.
Subject: Coil Winder From: "Gary Lindgren" gel@................. Date: Mon, 19 Jul 2010 06:31:34 -0700 Here is the one I use http://cgi.ebay.com/Manual-Coil-Winder-Power-Transformer-Winding-Machine-DI- /360279979429?cmd=ViewItem&pt=LH_DefaultDomain_2&hash=item53e25c35a5 Gary Gary Lindgren 585 Lincoln Ave Palo Alto CA 94301 650-326-0655 www.blue-eagle-technologies.com Check out Lastest Seismometer Reading cymonsplace.blogspot.com sites.google.com/site/seismicsensorinfo/Home Design Details for New Vertical Seismometer

Here is the one I use   = http://cgi.ebay.com/Manual-Coil-Winder-Power-Transformer-Winding-Ma= chine-DI-/360279979429?cmd=3DViewItem&pt=3DLH_DefaultDomain_2&has= h=3Ditem53e25c35a5

Gary

Gary Lindgren

585 Lincoln Ave

Palo Alto CA 94301

650-326-0655<= /span>

www.blue-eagle-technologies.com &nbs= p; Check out Lastest Seismometer = Reading

cymonsplace.blogspot.com =

sites.google.com/site/seismicsensorinfo/Home<= /a>    Design Details for New Vertical Seismometer

Subject: A Sticky Question From: "GPayton" gpayton@............. Date: Mon, 19 Jul 2010 08:42:55 -0500 In years past, I had difficulties in finding a "manual" coil winder and ended up with an old fashioned had drill. (As you know, you have to search using the correct words or your mouth pursed just right to be successful.) Anyway, that hand drill is what I ended up with. The EBay choices shown by Barry are interesting. Thanks, Barry. Never-the-less, in past, I had more trouble finding proper shaped ready-made spools or bobbins to wind a coil. And, if I tried to construct a rectangular shaped form, I had trouble getting the sandwiched parts to stick together! I suppose that I did not have the correct adhesive. I tried several without satisfaction. If anyone knows the secret to building a rectangular form, materials & glue, I'd appreciate knowing it. Regards, Jerry
In years past, I had difficulties in finding a "manual" coil = winder=20 and ended up with an old fashioned had drill. (As you know, you = have to=20 search using the correct words or your mouth pursed just right to = be=20 successful.)

Anyway, that hand drill is what I ended up with. The EBay = choices=20 shown by Barry are interesting. Thanks, Barry.

Never-the-less, in past, I had more trouble finding proper shaped=20 ready-made spools or bobbins to wind a coil. And, if I tried to = construct=20 a rectangular shaped form, I had trouble getting the sandwiched parts to = stick=20 together! I suppose that I did not have the correct = adhesive. I=20 tried several without satisfaction.

If anyone knows the secret to building a rectangular form, = materials &=20 glue, I'd appreciate knowing it.

Regards,

Jerry

Subject: Re: Velocity Sensor Question ? From: "Geoffrey" gmvoeth@........... Date: Mon, 19 Jul 2010 07:48:07 -0700 I understand the stability of the baseline is related to the DC nature of the balance between the + and - legs of the operational amplifier. Copper has a temperature coefficient which means it changes at a certian rate its resistance with temperature. If i balance both sides of the equation with identical physical properties, then I should expect they will change identically with temperature thus keeping the DC baseline steady. If you use only one copper coil on one leg this balance becomes impossible to achieve. This device will be located outside where temp changes are greatest. I do not know where you guys are coming from with your stable DC baselines unless you use some kind of miracle device which I have never found. Best Regards, geoff ----- Original Message ----- From: "Barry Lotz" To: Sent: Sunday, July 18, 2010 5:21 PM Subject: Re: Velocity Sensor Question ? Hi Geoff If you are measuring velocity not displacement there shouldn't be any temperature affects except maybe the electronics. There was a post awile back with a link to Ebay for a coil winding gismo for <$20. I'll see if I can find the link. Regards Barry http://www.seismicvault.com ________________________________ From: Geoffrey To: psn-l@.............. Sent: Sun, July 18, 2010 4:16:55 PM Subject: Re: Velocity Sensor Question ? Here is the preamp. I was going to place it right at the geophone. The two exact coils will change in step with temperature to keep a stable DC baseline. Minimal drift. http://gmvoeth.home.mchsi.com/AMP001.jpg Any reason this should not be right ? Will Larry sell only the coils ? I might get two to try my ideas. I looked into getting ten wound but the company was outragious in its (retooling fees) It seems they cant simply do it even tho they wind the things for a living. Thanks for your response. Best Regards, geoff PS: if PSN had a binary news server. we could post any kind of file for people to have/look at ? Could someone create a [alt.binaries.seismic.psn] news group, I understand there is a complex process but the creation is free and almost all ISP have one as part of their service. I have tried to understand the process but like Linux OS I cant understand it. I have tried Linux several times but cant make it functional. Fedora 10 installs OK but I just cant get it to be functional. ----- Original Message ----- From: "Brett Nordgren" To: Sent: Sunday, July 18, 2010 10:57 AM Subject: Re: Velocity Sensor Question ? > Hi Geoff, > > At 07:30 AM 7/18/2010, you wrote: >> Hello Mr. Nordgren; >> >> The question I have is thus: >> >> Is that coil right for the magnets or, >> Should it be rectangular in shape with the >> two vertical sides of the rectangle outside the magnetic flux ? > > Ideally you want your sensor to be linear. If you move the coil at a constant >speed over its mechanical range you would like to see a relatively constant >voltage out. You can achieve that in two ways. Have the magnet pole faces >large enough that all the coil wires stay well within the magnetic region, or >alternatively, make them small enough that all the magnetic lines stay within >the region filled with coil wires. When you have the edges of the magnetic >field moving across the outside or inside edges of the coil, the linearity >suffers, though perhaps not enough to worry about too much. > >> I figure I may need like 1206 feet of 36 AWG(B&S) copper enameled wire >> for a 2100 turns 500 ohm coil ? >> >> The 2100 turns are of enamled wire without a heavy coat of enamel. >> >> Is 2100 turns enough ? > > I guess the question would have to be, enough for what? It all depends on how >sensitive you plan to make your signal detection circuit--that is, how much >amplifier gain do you plan to have and if you are connecting to an A/D device, >what is its sensitivity? In general, I would try to start with the smallest >wire and the largest number of turns I could easily manage. Coil resistance of >several K Ohms wouldn't be unreasonable. The coil Larry sells I believe has >10,000 turns and is 9,000 Ohms. > >> Would it be better if the coil had a copper or iron core ? > > Definitely no. Iron would "suck in" the magnetic lines, away from the wires >where you want them to be. Copper, unless it made a complete loop, wouldn't do >much since it wouldn't be in the magnetic field, certainly nothing particularly >helpful. > >> This would mean a custom coil rectangular instead of circular. > > Possibly you'd get slightly better linearity with a rectangular coil and >rectangular magnet pole pieces, but either shape should work reasonably well for >what you are trying to do. > >> I think it may be possible to have two identical >> coils center tapped in the middle with a single >> rare earth magnet in the middle between the two >> coils then you have the right setup for >> a proper op amp differential circuit. > > I may be wrong, but I am suspecting that you are wanting to connect one output >to each of the two inputs of an op amp. If that is what you are thinking about, >the problem will be too much gain. Typical op amps have voltage gains of 100's >of thousands, or more often, millions. Generally for approximate analyses >designers assume that their gain is infinite. That means that extremely tiny >input signals (noise) would have the op amp output bouncing between its voltage >limits--not very useful. > > Usually op amps are connected up as single ended amplifiers using a >two-resistor feedback circuit, which makes a very nice voltage amplifier. > > See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure >3. > > If you do that, one coil will work fine, and by changing the resistor values >you can choose the amplifier gain to complement your coil sensitivity. The only >advantage I can think of for some kind of differential coil setup is that it >might not be as sensitive to 60 Hz hum. Though it probably wouldn't be that >hard to connect a differential coil to a single-ended amplifier, sort of like a >guitar "hum-bucking" pickup. > > An instrumentation amplifier *would* allow for independent connections to a >pair of coils, but they tend to be a lot more expensive and their gain usually >can't be adjusted as precisely. > > See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf Figure >2. > >> +COIL- NmagnetS +COIL- >> >> THE left coil - is connected to right coil + >> which is then the ground. >> >> Left Coil + goes to op amp + >> and >> Right coil - goes to op amp - >> >> The relative motion is magnet fixed to ground >> and coil fixed to device. >> >> Coil is stable and magnet moves right and left >> between the coils. >> >> Possibly +/- 2mm of range of motion. >> >> Each coil having 1050 to 2100 turns >> custom wound to be exactly the same. > > Hope that's a start, > Brett > > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. with the body of the >message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: A Sticky Question From: Barry Lotz barry_lotz@............. Date: Mon, 19 Jul 2010 08:13:27 -0700 (PDT) Jerry=0AI've successfully used acrylic=A0stock from a plastic supplier loca= lly with the =0Aappropriate glue.=A0I found that while machining or cutting= it I had to be careful =0Anot to get it hot. It will melt.=A0I used thin s= heets for the sides and round =0Astock or a thicker sheet cut in a=A0rectan= gle/square for the center. Finding the =0Acenter is challenging.=0A=A0Regar= ds=0ABarry=0Ahttp://www.seismicvault.com =0A=0A=0A=0A=0A___________________= _____________=0AFrom: GPayton =0ATo: psn-l@webtronic= s.com=0ASent: Mon, July 19, 2010 6:42:55 AM=0ASubject: A Sticky Question=0A= =0A=0AIn=A0years past, I had difficulties in finding a "manual" coil winder= and ended up =0Awith an old fashioned had drill.=A0 (As you know, you have= to search using the =0Acorrect words or your mouth pursed just right=A0to = be successful.)=0A=0AAnyway, that hand drill is what I ended up with.=A0 Th= e EBay choices shown by =0ABarry are interesting.=A0 Thanks, Barry.=0A=0ANe= ver-the-less, in past, I had more trouble finding proper shaped ready-made = =0Aspools or bobbins to wind a coil.=A0 And, if I tried to construct a rect= angular =0Ashaped form, I had trouble getting the sandwiched parts to stick= together!=A0 I =0Asuppose that I did not have the correct adhesive.=A0 I t= ried several without =0Asatisfaction.=0A=0AIf anyone knows the secret to bu= ilding a rectangular form, materials & glue, I'd =0Aappreciate knowing it.= =0A=0ARegards,=0AJerry
=0A
Jerry
=0A
I've successfully use= d acrylic stock from a plastic supplier locally with the appropriate g= lue. I found that while machining or cutting it I had to be careful no= t to get it hot. It will melt. I used thin sheets for the sides and ro= und stock or a thicker sheet cut in a rectangle/square for the center.= Finding the center is challenging.

Regards
Barry
http://www.se= ismicvault.com =0A

=0A

=0A
=0A
=0AFrom: GPayton <gpayton@.............>
To: psn-l@..............
Sent: Mon, July 19, 2010 6:42:55 AMSubject: A Sticky Question=

=0A=0A=0A<= DIV>In years past, I had difficulties in finding a "manual" coil winde= r and ended up with an old fashioned had drill. (As you know, you hav= e to search using the correct words or your mouth pursed just right to= be successful.)
=0A

=0A
Anyway, that hand drill i= s what I ended up with. The EBay choices shown by Barry are interesti= ng. Thanks, Barry.
=0A

=0A
Never-the-less, i= n past, I had more trouble finding proper shaped ready-made spools or bobbi= ns to wind a coil. And, if I tried to construct a rectangular shaped = form, I had trouble getting the sandwiched parts to stick together! I= suppose that I did not have the correct adhesive. I tried several wi= thout satisfaction.
=0A

=0A
If anyone knows the se= cret to building a rectangular form, materials & glue, I'd appreciate k= nowing it.
=0A

=0A
Regards,
=0A
Jerry=0A

=0A

Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:17:33 -0700 Hi J=F3n- I think the computer must have a loose card or=20 connection because it seems to be working fine=20 now. I plan on checking all boards and connections on my computer soon. Thanks for your thoughts George At 05:56 PM 7/18/2010, you wrote: >Hi, > >It might be a pre-earthquake to a larger earthquake. But only time is >going to tell you that. > >But I wonder why this small earthquake did manage to take your system >offline. I try to build my setup in that way that they can at least >withstand Mw6.5 earthquake. > >Regards, >J=F3n Fr=EDmann. > >On sun, 2010-07-18 at 14:32 -0700, George Bush wrote: > > Hello- > > > > This morning we had a M2.8 quake about 4 miles west of us out in the > > ocean and about 5 miles from the San Andreas fault that runs to the > > East of us. It was on a minor fault that runs parallel to the San > > Andreas. The shock knocked my data acquisition computer off-line, but > > was strong enough to jiggle the pen on my=20 > drum recorder that also was off line! > > > > I am wondering if the movement of the minor fault will add strain or > > relieve strain on the San Andreas fault (add or decrease the chances > > of the San Andreas fault letting-go). > > > > I would appreciate any thoughts or opinions on this from you PSN folks. > > > > > > George Bush > > Sea Ranch, CA, USA > > 38.73775N, 123.48882W > > > > __________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email PSN-L-REQUEST@.............. with > > the body of the message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html for more information. > > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George=20 __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:21:26 -0700 Jerry- Thanks for the thought, I think I have detected more small quakes from off-shore than from small faults on the other side of the San Andreas fault that are on-shore. George At 02:58 PM 7/18/2010, you wrote: >Hi George, > >I will do a flimsy attempt in answering you question. Yesterday, I >received the August issue of EARTH magazine with contained a sort >article about the Nazca Plate adjacent to Peru. The article was >titled Peruvian Plates Move With and Without Earthquakes. > >If I understood the article correctly, it was asking the question as >to why a block of the plate might move seismic and another part >generate an earthquake. It pointed out that the majority of the >earthquakes occur inland and not actually off shore at the >subducting ridge itself. > >In humble opinion, that may be because of lubrication from the >seawater, which would be less and less at the wedge-shaped plated >subducted underneath the South American Plate. THAT is strictly a >guess on my part, as I have NO technical training in geology or seismology! > >In regard to your question, I would think the same process "may" be >in play there and there may or may not be a direct interaction, who >knows. One might think that jostling a already stressed block might >cause it to release; and again it might just lessen the stress. > >I'd be interested in others opinions. Who knows, I might learn >something........Naaaaaa. > >Regards, >Jerry > >---------- >----- Original Message ----- >From: George Bush >To: psn-l@.............. >Sent: Sunday, July 18, 2010 4:32 PM >Subject: What are the implications of a M2.8 quake near the San Andreas fault? > >Hello- > >This morning we had a M2.8 quake about 4 miles west of us out in the >ocean and about 5 miles from the San Andreas fault that runs to the >East of us. It was on a minor fault that runs parallel to the San >Andreas. The shock knocked my data acquisition computer off-line, but >was strong enough to jiggle the pen on my drum recorder that also >was off line! > >I am wondering if the movement of the minor fault will add strain or >relieve strain on the San Andreas fault (add or decrease the chances >of the San Andreas fault letting-go). > >I would appreciate any thoughts or opinions on this from you PSN folks. > > >George Bush >Sea Ranch, CA, USA >38.73775N, 123.48882W > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email >PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See >http://www.seismicnet.com/maillist.html >for more information. George Jerry-

Thanks for the thought, I think I have detected more small quakes from off-shore than from small faults on the other side of the San Andreas fault that are on-shore.

George

At 02:58 PM 7/18/2010, you wrote:

Hi George,

I will do a flimsy attempt in answering you question. Yesterday, I received the August issue of EARTH magazine with contained a sort article about the Nazca Plate adjacent to Peru. The article was titled Peruvian Plates Move With and Without Earthquakes.

If I understood the article correctly, it was asking the question as to why a block of the plate might move seismic and another part generate an earthquake. It pointed out that the majority of the earthquakes occur inland and not actually off shore at the subducting ridge itself.

In humble opinion, that may be because of lubrication from the seawater, which would be less and less at the wedge-shaped plated subducted underneath the South American Plate. THAT is strictly a guess on my part, as I have NO technical training in geology or seismology!

In regard to your question, I would think the same process "may" be in play there and there may or may not be a direct interaction, who knows. One might think that jostling a already stressed block might cause it to release; and again it might just lessen the stress.

I'd be interested in others opinions. Who knows, I might learn something........Naaaaaa.

Regards,
Jerry

----- Original Message -----

From: George Bush

To: psn-l@..............

Sent: Sunday, July 18, 2010 4:32 PM

Subject: What are the implications of a M2.8 quake near the San Andreas fault?

Hello-

This morning we had a M2.8 quake about 4 miles west of us out in the

ocean and about 5 miles from the San Andreas fault that runs to the

East of us. It was on a minor fault that runs parallel to the San

Andreas. The shock knocked my data acquisition computer off-line, but

was strong enough to jiggle the pen on my drum recorder that also was off line!

I am wondering if the movement of the minor fault will add strain or

relieve strain on the San Andreas fault (add or decrease the chances

of the San Andreas fault letting-go).

I would appreciate any thoughts or opinions on this from you PSN folks.

George Bush

Sea Ranch, CA, USA

38.73775N, 123.48882W

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George Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:18:57 -0700 Thanks, that is what my family back in the center of the country tell me all the time! George At 02:49 PM 7/18/2010, you wrote: >Look out, that is the start, you guys are about to fall into the ocean!!! > >;-) > >I have no idea... > >Jeff > >On 18 Jul 2010 at 14:32, George Bush wrote: > > > Hello- > > > > This morning we had a M2.8 quake about 4 miles west of us out in the > > ocean and about 5 miles from the San Andreas fault that runs to the > > East of us. It was on a minor fault that runs parallel to the San > > Andreas. The shock knocked my data acquisition computer off-line, but > > was strong enough to jiggle the pen on my drum recorder that also > was off line! > > > > I am wondering if the movement of the minor fault will add strain or > > relieve strain on the San Andreas fault (add or decrease the chances > > of the San Andreas fault letting-go). > > > > I would appreciate any thoughts or opinions on this from you PSN folks. > > > > > > George Bush > > Sea Ranch, CA, USA > > 38.73775N, 123.48882W > > > > __________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email PSN-L-REQUEST@.............. with > > the body of the message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html for more information. > > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:22:39 -0700 Thanks Barry- That is a nice display, I will save the URL. George At 04:15 PM 7/18/2010, you wrote: >I keep an eye on this site. nice calif activity display >http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US10/32.42.-125.-115.php > >Regards >Barry >http://www.seismicvault.com > > > >From: GPayton >To: psn-l@.............. >Sent: Sun, July 18, 2010 2:58:02 PM >Subject: Re: What are the implications of a M2.8 quake near the San >Andreas fault? > >Hi George, > >I will do a flimsy attempt in answering you question. Yesterday, I >received the August issue of EARTH magazine with contained a sort >article about the Nazca Plate adjacent to Peru. The article was >titled Peruvian Plates Move With and Without Earthquakes. > >If I understood the article correctly, it was asking the question as >to why a block of the plate might move seismic and another part >generate an earthquake. It pointed out that the majority of the >earthquakes occur inland and not actually off shore at the >subducting ridge itself. > >In humble opinion, that may be because of lubrication from the >seawater, which would be less and less at the wedge-shaped plated >subducted underneath the South American Plate. THAT is strictly a >guess on my part, as I have NO technical training in geology or seismology! > >In regard to your question, I would think the same process "may" be >in play there and there may or may not be a direct interaction, who >knows. One might think that jostling a already stressed block might >cause it to release; and again it might just lessen the stress. > >I'd be interested in others opinions. Who knows, I might learn >something........Naaaaaa. > >Regards, >Jerry > >---------- >----- Original Message ----- >From: George Bush >To: psn-l@.............. >Sent: Sunday, July 18, 2010 4:32 PM >Subject: What are the implications of a M2.8 quake near the San Andreas fault? > >Hello- > >This morning we had a M2.8 quake about 4 miles west of us out in the >ocean and about 5 miles from the San Andreas fault that runs to the >East of us. It was on a minor fault that runs parallel to the San >Andreas. The shock knocked my data acquisition computer off-line, but >was strong enough to jiggle the pen on my drum recorder that also >was off line! > >I am wondering if the movement of the minor fault will add strain or >relieve strain on the San Andreas fault (add or decrease the chances >of the San Andreas fault letting-go). > >I would appreciate any thoughts or opinions on this from you PSN folks. > > >George Bush >Sea Ranch, CA, USA >38.73775N, 123.48882W > >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email >PSN-L-REQUEST@.............. with >the body of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George Thanks Barry-

That is a nice display, I will save the URL.

George

At 04:15 PM 7/18/2010, you wrote:

I keep an eye on this site. nice calif activity display
http://earthquake.usgs.gov/earthquakes/recenteqsus/Maps/US10/32.42.-125.-115.php

Regards
Barry
http://www.seismicvault.com

From: GPayton <gpayton@.............>
To: psn-l@..............
Sent: Sun, July 18, 2010 2:58:02 PM
Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault?

Hi George,

I will do a flimsy attempt in answering you question. Yesterday, I received the August issue of EARTH magazine with contained a sort article about the Nazca Plate adjacent to Peru. The article was titled Peruvian Plates Move With and Without Earthquakes.

If I understood the article correctly, it was asking the question as to why a block of the plate might move seismic and another part generate an earthquake. It pointed out that the majority of the earthquakes occur inland and not actually off shore at the subducting ridge itself.

In humble opinion, that may be because of lubrication from the seawater, which would be less and less at the wedge-shaped plated subducted underneath the South American Plate. THAT is strictly a guess on my part, as I have NO technical training in geology or seismology!

In regard to your question, I would think the same process "may" be in play there and there may or may not be a direct interaction, who knows. One might think that jostling a already stressed block might cause it to release; and again it might just lessen the stress.

I'd be interested in others opinions. Who knows, I might learn something........Naaaaaa.

Regards,
Jerry

----- Original Message -----

From: George Bush

To: psn-l@..............

Sent: Sunday, July 18, 2010 4:32 PM

Subject: What are the implications of a M2.8 quake near the San Andreas fault?

Hello-

This morning we had a M2.8 quake about 4 miles west of us out in the

ocean and about 5 miles from the San Andreas fault that runs to the

East of us. It was on a minor fault that runs parallel to the San

Andreas. The shock knocked my data acquisition computer off-line, but

was strong enough to jiggle the pen on my drum recorder that also was off line!

I am wondering if the movement of the minor fault will add strain or

relieve strain on the San Andreas fault (add or decrease the chances

of the San Andreas fault letting-go).

I would appreciate any thoughts or opinions on this from you PSN folks.

George Bush

Sea Ranch, CA, USA

38.73775N, 123.48882W

__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@.............. with

the body of the message (first line only): unsubscribe

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George Subject: Re: A Sticky Question From: "Geoffrey" gmvoeth@........... Date: Mon, 19 Jul 2010 08:23:19 -0700 "Finding the center is challenging" Isn't that just a matter of geometry or trig to find the center ? ----- Original Message ----- From: "Barry Lotz" To: Sent: Monday, July 19, 2010 8:13 AM Subject: Re: A Sticky Question Jerry I've successfully used acrylic stock from a plastic supplier locally with the appropriate glue. I found that while machining or cutting it I had to be careful not to get it hot. It will melt. I used thin sheets for the sides and round stock or a thicker sheet cut in a rectangle/square for the center. Finding the center is challenging. Regards Barry http://www.seismicvault.com ________________________________ From: GPayton To: psn-l@.............. Sent: Mon, July 19, 2010 6:42:55 AM Subject: A Sticky Question In years past, I had difficulties in finding a "manual" coil winder and ended up with an old fashioned had drill. (As you know, you have to search using the correct words or your mouth pursed just right to be successful.) Anyway, that hand drill is what I ended up with. The EBay choices shown by Barry are interesting. Thanks, Barry. Never-the-less, in past, I had more trouble finding proper shaped ready-made spools or bobbins to wind a coil. And, if I tried to construct a rectangular shaped form, I had trouble getting the sandwiched parts to stick together! I suppose that I did not have the correct adhesive. I tried several without satisfaction. If anyone knows the secret to building a rectangular form, materials & glue, I'd appreciate knowing it. Regards, Jerry __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:25:29 -0700 Thanks Geoff- I only worry because it is so close to the 'locked' San Andreas fault that is about due to go again (over 100 years since the 06 quake that displaced the fault up where I live by almost 20'). At 04:30 PM 7/18/2010, you wrote: >Hello Mr. Bush; > >I live 400 miles away to the EAST of LA and the quake >in 1994 rattled things all around here. > >Small quakes below like 5.0 are very common. > >I would not worry about one small quake. > >But you can be sure, CA will one day have a big one. > >They have charts (USGS) at places on the internet >which show research into high stress areas and >places like San Bernardino area is under great stress >now or so they believe. Washington State, Nevada, >They find high stresses where faults have not moved >in a long time. > >I suggest you research stress/strain as it relates to causing quakes. > >Or so I understand. > >Regards, >geoff > >----- Original Message ----- From: "George Bush" >To: >Sent: Sunday, July 18, 2010 2:32 PM >Subject: What are the implications of a M2.8 quake near the San Andreas fault? > > >>Hello- >>This morning we had a M2.8 quake about 4 miles west of us out in >>the ocean and about 5 miles from the San Andreas fault that runs to >>the East of us. It was on a minor fault that runs parallel to the >>San Andreas. The shock knocked my data acquisition computer >>off-line, but was strong enough to jiggle the pen on my drum >>recorder that also was off line! >>I am wondering if the movement of the minor fault will add strain >>or relieve strain on the San Andreas fault (add or decrease the >>chances of the San Andreas fault letting-go). >>I would appreciate any thoughts or opinions on this from you PSN folks. >> >>George Bush >>Sea Ranch, CA, USA >>38.73775N, 123.48882W >>__________________________________________________________ >>Public Seismic Network Mailing List (PSN-L) >>To leave this list email PSN-L-REQUEST@.............. with the body >>of the message (first line only): unsubscribe >>See http://www.seismicnet.com/maillist.html for more information. >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San From: George Bush ke6pxp@....... Date: Mon, 19 Jul 2010 08:33:32 -0700 Hello Mauro- Thank you for your thoughts and suggestions! I agree with you on the importance of these quakes and willtry to set up some procedure for monitoring and graphing them. George At 12:14 AM 7/19/2010, you wrote: >Hello, > >from far Italy i guess sharing some experience we have here may be useful. > >Single, spot event usually don't lead to any precursor. >Look to event sequences instead. >Check for sequence of earthquakes, they have to belong to the same >fault system and/or be focused on a constrained area (which can be >also rather large, this depends on the seismogenetic structures). > >Usually dangerous eq sequences follows the seismo structure you have. >Check then on the historical records of that area for as back in >time you can go and try to see time related patterns. > >Often the huge ground blocks push to each other and a fault depend >on the other, for sure you can find lot of literature about it for your area. > >Then draw a chart of magnitude of earthquake (Y axis) and time (X >axis) and see if magnitude and frequency increase or decrease. Pay >much attention if frequency and magnitude stops suddenly. > >If eq sequence go up in frequency and magnitude, stay in alert. >If eq sequence go slowily down in freq. and magnit. probably is only >an ew swarm that will exaust with no damages. > >best regards >Mauro > > > >Il 18/07/2010 23:32, George Bush ha scritto: >>Hello- >> >>This morning we had a M2.8 quake about 4 miles west of us out in the >>ocean and about 5 miles from the San Andreas fault that runs to the East >>of us. It was on a minor fault that runs parallel to the San Andreas. >>The shock knocked my data acquisition computer off-line, but was strong >>enough to jiggle the pen on my drum recorder that also was off line! >> >>I am wondering if the movement of the minor fault will add strain or >>relieve strain on the San Andreas fault (add or decrease the chances of >>the San Andreas fault letting-go). >> >>I would appreciate any thoughts or opinions on this from you PSN folks. >> >> >>George Bush >>Sea Ranch, CA, USA >>38.73775N, 123.48882W >>__________________________________________________________ >> >>Public Seismic Network Mailing List (PSN-L) >> >>To leave this list email PSN-L-REQUEST@.............. with the body of >>the message (first line only): unsubscribe >>See http://www.seismicnet.com/maillist.html for more information. >> >__________________________________________________________ > >Public Seismic Network Mailing List (PSN-L) > >To leave this list email PSN-L-REQUEST@.............. with the body >of the message (first line only): unsubscribe >See http://www.seismicnet.com/maillist.html for more information. George __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: Velocity Sensor Question ? From: Pete Rowe ptrowe@......... Date: Mon, 19 Jul 2010 08:41:18 -0700 (PDT) Geoff The secret miracle device that I use is a series coupling capacitor in the amplifier chain. The value I use is 4 uF but I only have a 3 second pendulum. AC couple the stages and the DC component becomes irrelevant. Make sure that the coupling caps are NON-POLAR. Don't use an electrolytic here. You can make up large values by paralleling smaller values. I hope this helps. Pete --- On Mon, 7/19/10, Geoffrey wrote: > From: Geoffrey > Subject: Re: Velocity Sensor Question ? > To: psn-l@.............. > Date: Monday, July 19, 2010, 7:48 AM > I understand the stability of the > baseline is related to the > DC nature of the balance between the + and - legs > of the operational amplifier. Copper has > a temperature coefficient which means it changes at a > certian rate its resistance with temperature. > If i balance both sides of the equation with identical > physical properties, then I should expect > they will change identically with temperature > thus keeping the DC baseline steady. > If you use only one copper coil on one leg this > balance becomes impossible to achieve. > This device will be located outside where > temp changes are greatest. > > I do not know where you guys are coming from > with your stable DC baselines unless you use > some kind of miracle device which I have never found. > > Best Regards, > geoff > > > > ----- Original Message ----- From: "Barry Lotz" > To: > Sent: Sunday, July 18, 2010 5:21 PM > Subject: Re: Velocity Sensor Question ? > > > Hi Geoff > If you are measuring velocity not displacement there > shouldn't be any temperature affects except maybe the > electronics. There was a post awile back with a link to Ebay > for a coil winding gismo for <$20. I'll see if I can find > the link. Regards > Barry > http://www.seismicvault.com > > > > ________________________________ > From: Geoffrey > To: psn-l@.............. > Sent: Sun, July 18, 2010 4:16:55 PM > Subject: Re: Velocity Sensor Question ? > > Here is the preamp. > I was going to place it right at the geophone. > The two exact coils will change in step > with temperature to keep a stable DC > baseline. Minimal drift. > > http://gmvoeth.home.mchsi.com/AMP001.jpg > > Any reason this should not be right ? > > Will Larry sell only the coils ? > I might get two to try my ideas. > > I looked into getting ten wound but the company > was outragious in its (retooling fees) > It seems they cant simply do it even tho they > wind the things for a living. > > Thanks for your response. > > Best Regards, > geoff > > PS: if PSN had a binary news server. > we could post any kind of file > for people to have/look at ? > Could someone create a [alt.binaries.seismic.psn] > news group, I understand there is a complex process > but the creation is free and almost all ISP have > one as part of their service. I have tried to understand > the process but like Linux OS I cant understand it. > I have tried Linux several times but cant make it > functional. > Fedora 10 installs OK but I just cant get it to be > functional. > > ----- Original Message ----- From: "Brett Nordgren" > To: > Sent: Sunday, July 18, 2010 10:57 AM > Subject: Re: Velocity Sensor Question ? > > > > Hi Geoff, > > > > At 07:30 AM 7/18/2010, you wrote: > >> Hello Mr. Nordgren; > >> > >> The question I have is thus: > >> > >> Is that coil right for the magnets or, > >> Should it be rectangular in shape with the > >> two vertical sides of the rectangle outside the > magnetic flux ? > > > > Ideally you want your sensor to be linear. If you move > the coil at a constant speed over its mechanical range you > would like to see a relatively constant voltage out. You can > achieve that in two ways. Have the magnet pole faces large > enough that all the coil wires stay well within the magnetic > region, or alternatively, make them small enough that all > the magnetic lines stay within the region filled with coil > wires. When you have the edges of the magnetic field moving > across the outside or inside edges of the coil, the > linearity suffers, though perhaps not enough to worry about > too much. > > > >> I figure I may need like 1206 feet of 36 > AWG(B&S) copper enameled wire > >> for a 2100 turns 500 ohm coil ? > >> > >> The 2100 turns are of enamled wire without a heavy > coat of enamel. > >> > >> Is 2100 turns enough ? > > > > I guess the question would have to be, enough for > what? It all depends on how sensitive you plan to make your > signal detection circuit--that is, how much amplifier gain > do you plan to have and if you are connecting to an A/D > device, what is its sensitivity? In general, I would try to > start with the smallest wire and the largest number of turns > I could easily manage. Coil resistance of several K Ohms > wouldn't be unreasonable. The coil Larry sells I believe has > 10,000 turns and is 9,000 Ohms. > > > >> Would it be better if the coil had a copper or > iron core ? > > > > Definitely no. Iron would "suck in" the magnetic > lines, away from the wires where you want them to be. > Copper, unless it made a complete loop, wouldn't do much > since it wouldn't be in the magnetic field, certainly > nothing particularly helpful. > > > >> This would mean a custom coil rectangular instead > of circular. > > > > Possibly you'd get slightly better linearity with a > rectangular coil and rectangular magnet pole pieces, but > either shape should work reasonably well for what you are > trying to do. > > > >> I think it may be possible to have two identical > >> coils center tapped in the middle with a single > >> rare earth magnet in the middle between the two > >> coils then you have the right setup for > >> a proper op amp differential circuit. > > > > I may be wrong, but I am suspecting that you are > wanting to connect one output to each of the two inputs of > an op amp. If that is what you are thinking about, the > problem will be too much gain. Typical op amps have voltage > gains of 100's of thousands, or more often, millions. > Generally for approximate analyses designers assume that > their gain is infinite. That means that extremely tiny input > signals (noise) would have the op amp output bouncing > between its voltage limits--not very useful. > > > > Usually op amps are connected up as single ended > amplifiers using a two-resistor feedback circuit, which > makes a very nice voltage amplifier. > > > > See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf > Figure 3. > > > > If you do that, one coil will work fine, and by > changing the resistor values you can choose the amplifier > gain to complement your coil sensitivity. The only advantage > I can think of for some kind of differential coil setup is > that it might not be as sensitive to 60 Hz hum. Though it > probably wouldn't be that hard to connect a differential > coil to a single-ended amplifier, sort of like a guitar > "hum-bucking" pickup. > > > > An instrumentation amplifier *would* allow for > independent connections to a pair of coils, but they tend to > be a lot more expensive and their gain usually can't be > adjusted as precisely. > > > > See: http://www.analog.com/static/imported-files/tutorials/MT-032.pdf > Figure 2. > > > >> +COIL- NmagnetS +COIL- > >> > >> THE left coil - is connected to right coil + > >> which is then the ground. > >> > >> Left Coil + goes to op amp + > >> and > >> Right coil - goes to op amp - > >> > >> The relative motion is magnet fixed to ground > >> and coil fixed to device. > >> > >> Coil is stable and magnet moves right and left > >> between the coils. > >> > >> Possibly +/- 2mm of range of motion. > >> > >> Each coil having 1050 to 2100 turns > >> custom wound to be exactly the same. > > > > Hope that's a start, > > Brett > > > > > > > > > __________________________________________________________ > > > > Public Seismic Network Mailing List (PSN-L) > > > > To leave this list email PSN-L-REQUEST@.............. > with the body of the message (first line only): unsubscribe > > See http://www.seismicnet.com/maillist.html > for more information. > > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. > with the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html > for more information. > > __________________________________________________________ > > Public Seismic Network Mailing List (PSN-L) > > To leave this list email PSN-L-REQUEST@.............. > with the body of the message (first line only): unsubscribe > See http://www.seismicnet.com/maillist.html > for more information. > __________________________________________________________ Public Seismic Network Mailing List (PSN-L) Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? From: "GPayton" gpayton@............. Date: Mon, 19 Jul 2010 10:40:10 -0500 No problem. As I said, it is just my uneducated "guess", at its best. I found the article interesting in that I had noticed the EQ's mostly occurred inland from the ridge, as well as the mountain building aspect. I think I would be a little nervous too, if I lived that close to the San Andreas fault. But, short of moving, what can you do? Best Regards, Jerry ----- Original Message ----- From: George Bush To: psn-l@.............. Sent: Monday, July 19, 2010 10:21 AM Subject: Re: What are the implications of a M2.8 quake near the San Andreas fault? Jerry- Thanks for the thought, I think I have detected more small quakes from off-shore than from small faults on the other side of the San Andreas fault that are on-shore. George At 02:58 PM 7/18/2010, you wrote: Hi George, I will do a flimsy attempt in answering you question. Yesterday, I received the August issue of EARTH magazine with contained a sort article about the Nazca Plate adjacent to Peru. The article was titled Peruvian Plates Move With and Without Earthquakes. If I understood the article correctly, it was asking the question as to why a block of the plate might move seismic and another part generate an earthquake. It pointed out that the majority of the earthquakes occur inland and not actually off shore at the subducting ridge itself. In humble opinion, that may be because of lubrication from the seawater, which would be less and less at the wedge-shaped plated subducted underneath the South American Plate. THAT is strictly a guess on my part, as I have NO technical training in geology or seismology! In regard to your question, I would think the same process "may" be in play there and there may or may not be a direct interaction, who knows. One might think that jostling a already stressed block might cause it to release; and again it might just lessen the stress. I'd be interested in others opinions. Who knows, I might learn something........Naaaaaa. Regards, Jerry ---------------------------------------------------------------------------- ----- Original Message ----- From: George Bush To: psn-l@.............. Sent: Sunday, July 18, 2010 4:32 PM Subject: What are the implications of a M2.8 quake near the San Andreas fault? Hello- This morning we had a M2.8 quake about 4 miles west of us out in the ocean and about 5 miles from the San Andreas fault that runs to the East of us. It was on a minor fault that runs parallel to the San Andreas. The shock knocked my data acquisition computer off-line, but was strong enough to jiggle the pen on my drum recorder that also was off line! I am wondering if the movement of the minor fault will add strain or relieve strain on the San Andreas fault (add or decrease the chances of the San Andreas fault letting-go). I would appreciate any thoughts or opinions on this from you PSN folks. George Bush Sea Ranch, CA, USA 38.73775N, 123.48882W __________________________________________________________ Public Seismic Network Mailing List (PSN-L) To leave this list email PSN-L-REQUEST@.............. with the body of the message (first line only): unsubscribe See http://www.seismicnet.com/maillist.html for more information. George
No problem. As I said, it is just my uneducated "guess", at = its=20 best. I found the article interesting in that I had noticed the = EQ's=20 mostly occurred inland from the ridge, as well as the mountain building=20 aspect.

I think I would be a little nervous too, if I lived that close to = the San=20 Andreas fault. But, short of moving, what can you do?

Best Regards,

Jerry

----- Original Message -----
From:=20 George = Bush

To: psn-l@..............

Sent: Monday, July 19, 2010 = 10:21=20 AM

Subject: Re: What are the = implications of=20 a M2.8 quake near the San Andreas fault?

Jerry-

Thanks for the thought, I think I have = detected=20 more small quakes from off-shore than from small faults on the other = side of=20 the San Andreas fault that are on-shore.

George

At 02:58 = PM=20 7/18/2010, you wrote:

Hi = George,

I will do=20 a flimsy attempt in answering you question. Yesterday, I = received the=20 August issue of EARTH magazine with contained a sort article = about the=20 Nazca Plate adjacent to Peru. The article was titled = Peruvian=20 Plates Move With and Without Earthquakes.

If I = understood=20 the article correctly, it was asking the question as to why a block = of the=20 plate might move seismic and another part generate an = earthquake. It=20 pointed out that the majority of the earthquakes occur inland and = not=20 actually off shore at the subducting ridge itself.

In = humble=20 opinion, that may be because of lubrication from the seawater, which = would=20 be less and less at the wedge-shaped plated subducted underneath the = South=20 American Plate. THAT is strictly a guess on my part, as I have = NO=20 technical training in geology or seismology!

In regard = to your=20 question, I would think the same process "may" be in play there and = there=20 may or may not be a direct interaction, who knows. One might = think=20 that jostling a already stressed block might cause it to release; = and again=20 it might just lessen the stress.

I'd be interested in = others=20 opinions. Who knows, I might learn=20 something........Naaaaaa.

Regards,
Jerry

----- Original Message -----

From: George Bush =

To: psn-l@..............=20

Sent: Sunday, July 18, 2010 4:32 PM

Subject: What are the implications of a M2.8 quake near = the San=20 Andreas fault?

Hello-

This morning we had a M2.8 quake about 4 miles west of us out = in the=20

ocean and about 5 miles from the San Andreas fault that runs = to the=20

East of us. It was on a minor fault that runs parallel to the = San

Andreas. The shock knocked my data acquisition computer = off-line, but=20

was strong enough to jiggle the pen on my drum recorder that = also was=20 off line!

I am wondering if the movement of the minor fault will add = strain or=20

relieve strain on the San Andreas fault (add or decrease the = chances=20

of the San Andreas fault letting-go).

I would appreciate any thoughts or opinions on this from you = PSN=20 folks.

George Bush

Sea Ranch, CA, USA

38.73775N, 123.48882W

=
__________________________________________________________

Public Seismic Network Mailing List (PSN-L)

To leave this list email PSN-L-REQUEST@............... =20 with

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George Subject: RE: A Sticky Question From: "Gary Lindgren" gel@................. Date: Mon, 19 Jul 2010 09:02:47 -0700 Jerry, I have built coil forms using the design of Chris Chapman. I use .062" circuit board material without the copper layer. I cut out the shapes with a saw and use a Dremel tool to cut slots as needed and use epoxy to bond it all together. Gary From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of GPayton Sent: Monday, July 19, 2010 6:43 AM To: psn-l@.............. Subject: A Sticky Question In years past, I had difficulties in finding a "manual" coil winder and ended up with an old fashioned had drill. (As you know, you have to search using the correct words or your mouth pursed just right to be successful.) Anyway, that hand drill is what I ended up with. The EBay choices shown by Barry are interesting. Thanks, Barry. Never-the-less, in past, I had more trouble finding proper shaped ready-made spools or bobbins to wind a coil. And, if I tried to construct a rectangular shaped form, I had trouble getting the sandwiched parts to stick together! I suppose that I did not have the correct adhesive. I tried several without satisfaction. If anyone knows the secret to building a rectangular form, materials & glue, I'd appreciate knowing it. Regards, Jerry

Jerry,

I have built coil forms using the design of Chris = Chapman. I use ..062" circuit board material without the copper layer. I cut out = the shapes with a saw and use a Dremel tool to cut slots as needed and use epoxy to = bond it all together.

Gary

From:= psn-l-request@.............. [mailto:psn-l-request@............... On = Behalf Of GPayton
Sent: Monday, July 19, 2010 6:43 AM
To: psn-l@..............
Subject: A Sticky Question

In years past, I had difficulties in finding a "manual" coil winder and ended up with an old fashioned had drill. (As you know, you have to search using the correct words or = your mouth pursed just right to be successful.)

Anyway, that hand drill is what I ended up = with. The EBay choices shown by Barry are interesting. Thanks, = Barry.

Never-the-less, in past, I had more trouble finding = proper shaped ready-made spools or bobbins to wind a coil. And, if I = tried to construct a rectangular shaped form, I had trouble getting the = sandwiched parts to stick together! I suppose that I did not have the correct adhesive. I tried several without satisfaction.

If anyone knows the secret to building a = rectangular form, materials & glue, I'd appreciate knowing it.

Regards,

Jerry

Subject: Re: A Sticky Question From: "Kay Wyatt" kwyatt@............. Date: Mon, 19 Jul 2010 09:15:03 -0700 Here is the link to Chris Chapman's coil design and instructions http://www.jclahr.com/science/psn/chapman/lehman/index.html By the way, has anybody heard how Chris is doing? I miss hearing from = him on this net. Kay Wyatt ----- Original Message -----=20 From: Gary Lindgren=20 To: psn-l@................. Sent: Monday, July 19, 2010 9:02 AM Subject: RE: A Sticky Question Jerry, I have built coil forms using the design of Chris Chapman. I use .062" = circuit board material without the copper layer. I cut out the shapes = with a saw and use a Dremel tool to cut slots as needed and use epoxy to = bond it all together.=20 Gary =20 =20 =20 =20 =20 =20 From: psn-l-request@.............. = [mailto:psn-l-request@............... On Behalf Of GPayton Sent: Monday, July 19, 2010 6:43 AM To: psn-l@.............. Subject: A Sticky Question =20 In years past, I had difficulties in finding a "manual" coil winder = and ended up with an old fashioned had drill. (As you know, you have to = search using the correct words or your mouth pursed just right to be = successful.) =20 Anyway, that hand drill is what I ended up with. The EBay choices = shown by Barry are interesting. Thanks, Barry. =20 Never-the-less, in past, I had more trouble finding proper shaped = ready-made spools or bobbins to wind a coil. And, if I tried to = construct a rectangular shaped form, I had trouble getting the = sandwiched parts to stick together! I suppose that I did not have the = correct adhesive. I tried several without satisfaction. =20 If anyone knows the secret to building a rectangular form, materials & = glue, I'd appreciate knowing it. =20 Regards, Jerry =20 =20
Here is the link to Chris Chapman's = coil design and=20 instructions

http= ://www.jclahr.com/science/psn/chapman/lehman/index.html

By the way, has anybody heard how Chris = is=20 doing? I miss hearing from him on this net.

Kay Wyatt

----- Original Message -----
From:=20 Gary=20 Lindgren

To: psn-l@..............

Sent: Monday, July 19, 2010 = 9:02 AM

Subject: RE: A Sticky = Question

Jerry,

I=20 have built coil forms using the design of Chris Chapman. I use .062" = circuit=20 board material without the copper layer. I cut out the shapes with a = saw and=20 use a Dremel tool to cut slots as needed and use epoxy to bond it all=20 together.

Gary

From: psn-l-request@............... =20 [mailto:psn-l-request@............... On Behalf Of=20 GPayton
Sent: Monday, July 19, 2010 6:43 = AM
To:=20 psn-l@..............
Subject: A Sticky=20 Question

In years past, I had difficulties in finding = a=20 "manual" coil winder and ended up with an old fashioned had = drill. (As=20 you know, you have to search using the correct words or your mouth = pursed just=20 right to be successful.)

Anyway, that hand drill is what I ended up = with. The=20 EBay choices shown by Barry are interesting. Thanks,=20 Barry.

Never-the-less, in past, I had more trouble = finding proper=20 shaped ready-made spools or bobbins to wind a coil. And, if I = tried to=20 construct a rectangular shaped form, I had trouble getting the = sandwiched=20 parts to stick together! I suppose that I did not have the = correct=20 adhesive. I tried several without = satisfaction.

If anyone knows the secret to building a = rectangular form,=20 materials & glue, I'd appreciate knowing it.

Regards,

Jerry

Subject: Re: A Sticky Question From: "GPayton" gpayton@............. Date: Mon, 19 Jul 2010 11:26:33 -0500 Thank you Kay, good to hear from you. I sent a private email just last week and have not heard back from his wife. The last I heard was that he was still hospitalized and fighting whatever the problem was (I did not pry). I believe it to be serious, but yet unidentified to me. Thank you again for the URL. Back in 1998 he had suggested a glass type PCB and that is where I fell into trouble (if I remember correctly.) Regards, Jerry -------------------------------------------------------------------------------- ----- Original Message ----- From: Kay Wyatt To: psn-l@.............. Sent: Monday, July 19, 2010 11:15 AM Subject: Re: A Sticky Question Here is the link to Chris Chapman's coil design and instructions http://www.jclahr.com/science/psn/chapman/lehman/index.html By the way, has anybody heard how Chris is doing? I miss hearing from him on this net. Kay Wyatt ----- Original Message ----- From: Gary Lindgren To: psn-l@.............. Sent: Monday, July 19, 2010 9:02 AM Subject: RE: A Sticky Question Jerry, I have built coil forms using the design of Chris Chapman. I use .062" circuit board material without the copper layer. I cut out the shapes with a saw and use a Dremel tool to cut slots as needed and use epoxy to bond it all together. Gary From: psn-l-request@.............. [mailto:psn-l-request@............... On Behalf Of GPayton Sent: Monday, July 19, 2010 6:43 AM To: psn-l@.............. Subject: A Sticky Question In years past, I had difficulties in finding a "manual" coil winder and ended up with an old fashioned had drill. (As you know, you have to search using the correct words or your mouth pursed just right to be successful.) Anyway, that hand drill is what I ended up with. The EBay choices shown by Barry are interesting. Thanks, Barry. Never-the-less, in past, I had more trouble finding proper shaped ready-made spools or bobbins to wind a coil. And, if I tried to construct a rectangular shaped form, I had trouble getting the sandwiched parts to stick together! I suppose that I did not have the correct adhesive. I tried several without satisfaction. If anyone knows the secret to building a rectangular form, materials & glue, I'd appreciate knowing it. Regards, Jerry
Thank you Kay, good to hear from you.

I sent a private email just last week and have not heard back from = his=20 wife. The last I heard was that he was still hospitalized and = fighting=20 whatever the problem was (I did not pry). I believe it to be = serious, but=20 yet unidentified to me.

Thank you again for the URL. Back in 1998 he had suggested a = glass=20 type PCB and that is where I fell into trouble (if I remember = correctly.)

Regards,

Jerry

----- Original Message -----
From:=20 Kay Wyatt=20

To: psn-l@..............

Sent: Monday, July 19, 2010 = 11:15=20 AM

Subject: Re: A Sticky = Question

Here is the link to Chris Chapman's = coil design=20 and instructions

http= ://www.jclahr.com/science/psn/chapman/lehman/index.html

By the way, has anybody heard how = Chris is=20 doing? I miss hearing from him on this net.

Kay Wyatt

----- Original Message -----
From:=20 Gary=20 Lindgren