[time-nuts] Cable length calibration

[Poul-Henning Kamp]

--------
In message <20160629192850.19C2940605C at ip-64-139-1-69.sjc.megapath.net>, Hal Mu
rray writes:

>> At one point they were looking into making a GPS time receiver where the
>> cable length calibration would be built-in. 
>
>How would you do that?

TDR ?

If it wasn't behind a choke, the inrush current to the antenna
preamp power filtering capacitor could be measured, but the choke
ruins that.

The trouble is how to do it without frying the antenna preamp...


Seriously...

GPS antennas and receivers are cheap, I would just use two GPS antennas
with a known difference in cable-length.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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