From: tchannel1@............

Date: Tue, 9 Oct 2007 14:55:46 -0600

Hi Jerry, "I Think"................Q 1 The p and s and other = phases if you use them are all based on (time theory) =20 The math program knows where you are and where the event took place, it = converts that info to Miles, also to Degrees. It then uses one of several formulas, I use the default formula, to = place the p and s on a time line, which is on the bottom of the Winquake = screen. Q2.........The distance is "around the surface" like a string on a = globe. This is all "great circle" math. So the program is simple for this part, because, it take the event Long. = and Lat, your Long. and Lat, the time of the event, does the math (the = p travels about 10km per second), I calculate it is about 28,000 miles = per hour, and figure it would take the P, say 12.002 minute to reach = you, add that, to the event time, and places the P on your screen = accordingly. It does not read you recording, you could have recorded a truck or a = train and if the event matched your train in would place the p and s, on = the time line. Is this clear??????????????????? Ted ----- Original Message -----=20 From: Jerry Payton=20 To: psn-l@................. Sent: Tuesday, October 09, 2007 1:01 PM Subject: WinQuake Display Question (Question 1): On a WinQuake event display are the P and S arrival = times showning the ACTUAL arrival times or shown according to what the = table says they should be? (Question 2): Is the distance from the event to your seismograph = computed "through the earth" or "around the surface?" Thank you, Jerry PaytonHi Jerry, "I = Think"................Q=20 1 The p and s and other phases = if you=20 use them are all based on (time theory)The math program knows where you are = and where the=20 event took place, it converts that info to Miles, also to = Degrees.It then uses one of several = formulas, I use=20 the default formula, to place the p and s on a time line, which is = on the=20 bottom of the Winquake screen.Q2.........The distance is "around the = surface"=20 like a string on a globe. This is all "great circle"=20 math.So the program is simple for this part, = because, it=20 take the event Long. and Lat, your Long. and Lat, the time of the = event,=20 does the math (the p travels about 10km per second), I calculate it is = about=20 28,000 miles per hour, and figure it would take the P, say 12.002 = minute=20 to reach you, add that, to the event time, and places the P on your = screen=20 accordingly.It does not read you recording, = you could=20 have recorded a truck or a train and if the event matched your train in = would=20 place the p and s, on the time line.Is this = clear??????????????????? =20 Ted----- Original Message -----From:=20 Jerry = Payton=20Sent:Tuesday, October 09, 2007 = 1:01=20 PMSubject:WinQuake Display = Question(Question 1): On a WinQuake event display = are the=20 P and S arrival times showning theACTUALarrival = times or=20 shown according to what the table says they should be?(Question 2): Is the distance from the event to = your seismograph computed "through the earth" or "around the=20 surface?"Thank you,Jerry Payton