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Author Topic: All 1 PPS pip / pulse / tick logs here please  (Read 45722 times)

Offline Josh

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Re: All 1 PPS pip / pulse / tick logs here please
« Reply #135 on: November 30, 2021, 0027 UTC »
Wcode chu mode (inverted) said this;
Year: 2021,   TAI-UTC: 37s,   DUT1: -0.1s,   no Leap Second,   DSTpatCode:  7
  Day: 330,   Hour:  2,   Minute: 31,   Second: 33
  Day: 330,   Hour:  2,   Minute: 31,   Second: 34
  Day: 330,   Hour:  2,   Minute: 31,   Second: 35
  Day: 330,   Hour:  2,   Minute: 31,   Second: 36
  Day: 330,   Hour:  2,   Minute: 31,   Second: 37
  Day: 330,   Hour:  2,   Minute: 31,   Second: 38
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Offline Token

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Re: All 1 PPS pip / pulse / tick logs here please
« Reply #136 on: November 30, 2021, 0345 UTC »
Wcode chu mode (inverted) said this;
Year: 2021,   TAI-UTC: 37s,   DUT1: -0.1s,   no Leap Second,   DSTpatCode:  7
  Day: 330,   Hour:  2,   Minute: 31,   Second: 33
  Day: 330,   Hour:  2,   Minute: 31,   Second: 34
  Day: 330,   Hour:  2,   Minute: 31,   Second: 35
  Day: 330,   Hour:  2,   Minute: 31,   Second: 36
  Day: 330,   Hour:  2,   Minute: 31,   Second: 37
  Day: 330,   Hour:  2,   Minute: 31,   Second: 38

That roughly matches the day and time he reported.  Also, if I remember right, CHU transmits its data mode in seconds 31 to 39.  Listening to the MP3 file there are 9 bursts of data, your decode shows 5 of those 9, and match when CHU would have been sending data.

So, someone (I assume pirate base don freq choice) retransmitting CHU audio?  Or something else?

T!
T!
Mojave Desert, California USA

Offline ~SIGINT~

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Re: All 1 PPS pip / pulse / tick logs here please
« Reply #137 on: November 30, 2021, 2328 UTC »
Correct, CHU sends the digital time code between the 31st and 39th seconds past the minute as 10 characters at 300 bits per second using 8N2 asynchronous serial communication following the Bell 103 compatible 300 baud modem waveform.

Offline Josh

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Re: All 1 PPS pip / pulse / tick logs here please
« Reply #138 on: December 10, 2021, 1855 UTC »
Wcode chu mode (inverted) said this;
Year: 2021,   TAI-UTC: 37s,   DUT1: -0.1s,   no Leap Second,   DSTpatCode:  7
  Day: 330,   Hour:  2,   Minute: 31,   Second: 33
  Day: 330,   Hour:  2,   Minute: 31,   Second: 34
  Day: 330,   Hour:  2,   Minute: 31,   Second: 35
  Day: 330,   Hour:  2,   Minute: 31,   Second: 36
  Day: 330,   Hour:  2,   Minute: 31,   Second: 37
  Day: 330,   Hour:  2,   Minute: 31,   Second: 38

That roughly matches the day and time he reported.  Also, if I remember right, CHU transmits its data mode in seconds 31 to 39.  Listening to the MP3 file there are 9 bursts of data, your decode shows 5 of those 9, and match when CHU would have been sending data.

So, someone (I assume pirate base don freq choice) retransmitting CHU audio?  Or something else?

T!

That'd be easier than rolling your own version of the chu modem I guess.
We do not encourage any radio operations contrary to regulations.