[time-nuts] LORAN-C

[Poul-Henning Kamp]

In message <4FA006E8.5040304 at verizon.net>, "Stan, W1LE" writes:

>I will use a HP-3336C with the station 10 MHz (GPS/DO) reference.
>
>Typo:  trigger should really be 11.148272 Hz instead of KHz !

You need a really amazing stable and noise-free trigger to lock
onto a 5.5Hz (see below) sine at the required level of stability
(~2usec).

I used my HP33120A once, but its square output is made with a
comparator on the sine wave, and has pretty bad jitter.
Switching to saw-tooth solved that, defining my own arbitrary
square-wave was even better, not sure why.

You want 1/(2*.089700) = 5.574136 Hz, otherwise every other
loran-c pulse will cancel out due to the A/B coding polarity.

If you don't have a counter-based signal generator, consider stealing
a GRI or FRI-rate signal from one of your loran-C receivers, I belive
the AUSTRON 2000/2100 offers it on a BNC at the backside.

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