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Date: Wed, 30 Jan 2002 16:30:45 +0000
To: rsgb_lf_group@blacksheep.org
From: "James Moritz" <j.r.moritz@herts.ac.uk>
Subject: LF: Re: Frequency standards for LF.  The next generation
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Dear Andy, LF Group,

Thanks for writing about this very interesting project -

At 15:17 28/01/2002 +0000, you wrote:
>The effect is to keep the VCXO precisely locked in the long term to the GPS
>signal, although in the short term it's instantaneous phase is jittering,
>and therefore the frequency is shifting by a Hz or two every second.  By
>apropriate choice of charge pump R/C values, the jitter can be minimised.
>When this source is subsequently divided down to LF, the phase shift is
>reduced by the division factor.


What is the source of the jitter here - is it being introduced by the 
stabilisation circuit, or that due to the VCXO itself? Also, I can see that 
it would not matter much for long symbol lengths like Jason or you coherent 
PSK system, but would the jitter be a problem for something like WOLF, with 
it's 10 bits/s?

Cheers, Jim Moritz
73 de M0BMU