Message-ID: <1611e7d66bb.marcocadeddu@tin.it>
Date: Mon, 22 Jan 2018 16:29:50 +0100 (CET)
From: "marcocadeddu@tin.it" <marcocadeddu@tin.it>
To:  <rsgb_lf_group@blacksheep.org>
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Subject: R: LF: GPS locked frequency standard
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Hi Paul,

what a neat layout! :-)

73, Marco IK1HSS

P.S. a bit out but tuned to LF/VLF... I'll support the wish of Roger 
concerning an EbNaut idiot's guide.. I made some test when started the 
first LF transmission but I forgot all about SL config etc.. I mean 
that if somebody will so kind to write the guide probably more reports 
arrive ;-)

----Messaggio originale----
Da: vlf0403@abelian.org
Data: 22-gen-2018 7.58
A: <rsgb_lf_group@blacksheep.org>
Ogg: LF: GPS locked frequency standard


A GPS based frequency standard I put together over the weekend.

  http://abelian.org/vlf/tmp/180121a.jpg  http://abelian.org/vlf/tmp/180121b.jpg

Based on a Trimble 57963 GPS disciplined OCXO, I added a divider
and power supply.  It produces signals with very good short
term and long term phase stability.   There is a DC coupled
output (CMOS logic level) and AC coupled (for sound card input).

It's an arrangement I've often used for testing sound cards and
changes to vttime, but each time I cobbled together a divider
on breadboard.  Now finally got around to putting it in a box,
it is much simpler to use.

I'm intending to do a lot more work on the Raspberry Pi and
Octo card combination so will be making plenty of use of this.

--
Paul Nicholson
--