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Discussion of precise time and frequency measurement

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Re: [time-nuts] GPS receiver time message offsets to 1PPS

HM
Hal Murray
Tue, Jul 26, 2016 12:45 AM

Here are the results of measuring the difference between the time code in a
GPS receiver time message and the arrival time of the last byte of the
message.  Negative values mean that the receiver sends the timing message
after the 1PPS pulse that it describes. The table also shows the standard
deviation of the message arrival times.

Neat.  Thanks.

holrum@hotmail.com said:
(slight snippage to avoid line wraps)

Z3812A    ...  1450.5      0.6  (ramps 950 .. 1950 over 1000 secs)
Z3801A    ...  1341.5      2.0  (ramps 941 .. 1841 over 1000 secs)

Those ramps don't make sense to me.  Mine are consistently right on.

Are you using T1 or T2 format?  t1 is the default.  I'm using T2.  (Seems
unlikely it would make a difference, but stranger things have happened.)

--
These are my opinions.  I hate spam.

holrum@hotmail.com said: > Here are the results of measuring the difference between the time code in a > GPS receiver time message and the arrival time of the last byte of the > message. Negative values mean that the receiver sends the timing message > after the 1PPS pulse that it describes. The table also shows the standard > deviation of the message arrival times. Neat. Thanks. holrum@hotmail.com said: (slight snippage to avoid line wraps) > Z3812A ... 1450.5 0.6 (ramps 950 .. 1950 over 1000 secs) > Z3801A ... 1341.5 2.0 (ramps 941 .. 1841 over 1000 secs) Those ramps don't make sense to me. Mine are consistently right on. Are you using T1 or T2 format? t1 is the default. I'm using T2. (Seems unlikely it would make a difference, but stranger things have happened.) -- These are my opinions. I hate spam.