[time-nuts] FE-5680A arrived

Chris Albertson albertson.chris at gmail.com
Wed Jan 11 23:32:09 UTC 2012


>  If you don't have a scope or TIC to  get the Rbs PPS offset from GPS, you
> can let NTP do it for you.

You don't even need NTP.  The linux PPS driver tags every pulse with a
nanosecond time tag.   (But on almost all computers the time stamp
will have uSec resolution and the lower order digits will be some
fixed random value.)      Run the program "ppstest" to write these
tags human readable form.

So if you have PC hardware with a serial port, you have a TIC,
interfaced to a computer logger good to about 1 or 2 uS with as many
input channles as you have serial or parallel ports.

Some people are using this to measure 60Hz mains power frequency.
Simply connect AC (using some safe method) to pin one of a serial port
and every cycle gets time stamped.  The system is fast enough to log
1000 per second easy.


Chris Albertson
Redondo Beach, California




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