PSN-L Email List Message
Subject: Re: Help me LEARN
From: =?ISO-8859-1?Q?J=F3n_Fr=EDmann?= jonfr@.........
Date: Sat, 27 Feb 2010 13:02:39 +0000
Using radio signal for time in earthquake mesurement is quite
inaccurate. You should get a GPS clock, as you just have to buy it once
and set it up once. It is not that expensive in the long run.
On lau, 2010-02-27 at 05:45 -0700, Geoffrey wrote:
> It is not unusual to get signals several seconds
> in difference to the models.
> Your tables should be designed
> for your exact geographic location.
> The models used by Winquake are most likely
> a general type table.
> The thing I like are those theoretical tables
> built by the USGS as they relate to your position and
> the earthquake in question.
> Sometimes but not always. I get results almost exactly
> the same as those theoretical computations.
> I compare my signals with Phoenix initially.
> Most always I get results consistent with
> my location relative to Phoenix and
> the Earthquake.
> I missed this last 8.8 EQ because if my
> times has not been calibrated within the last 24 hours
> I simply turn off the program collecting the info
> till I can get the clock set to WWV.
> I use a free running modulo counter to
> calibrate my times due to the fact
> my WWV radio signal is horrible and I can
> not afford the opportunity costs to have
> a GPS calibration and I will not run
> a time sharing program to collect information
> like Windows.
> I consider my times very good
> when the clock is properly set.
> Very good to me is like +/- 0.1 second.
> But to the USGS its probably more like +/- 0.000000001 second.
> Light travels in a vacuum (Deep Space) maybe 11.8 inches in this time.
> If your times are a bit off after calibrating
> and coordinating your time do not worry
> about a few seconds of difference.
> After all, we are Armatures and not serious scientists.
> Gut Luk Comrade, :-)
> ----- Original Message -----=20
> From: "GPayton"
> To: "PSN Network List"
> Sent: Friday, February 26, 2010 8:04 AM
> Subject: Help me LEARN
> > After reading many posts on the PSN Net, it is obvious that I know very=
> > little as compared to MANY of you out there. I am often embarrassed t=
> > a question and turn to the books to try to resolve my question(s). Eve=
> > that, many time I fall short.
> > So! Question:
> > 1) Today's trace of the 3.1 event in Oklahoma displays in WinQua=
> > that both the Pb & Sb were seconds BEFORE the P & S times. To me, that=
> > seems like I get a bouncing ball BEFORE I actually drop it! What did I=
> > wrong? Is this a matter of the "tables" being off? Or, am I wrong in=20
> > assuming it is incorrect?
> > 2) Another "pause" that I have when using WinQuake of any event i=
> > HOW LONG to plot it. Obviously, a local event would be short, a region=
> > would be a little longer and a teleseismic may be over an hour. But, I=
> > wondering IF there was a rule-of-thumb time that you experienced people=
> > Thanks & Best regards,
> > Jerry=20
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