Clemens wrote:

> http://www.jrmiller.demon.co.uk/projects/ministd/frqstd.htm

That looks well made, similar price to the going rate
for a Trimble Thunderbolt.   Tempted!

There is rumour of a firmware upgrade for the BG7TBL device to fix
that frequency error problem.

I have emailed BG7TBL to see what can be done.  I'm reluctant to
write it off because the OCXO is supposed to be quite good.

Meanwhile one of these has been ordered

  https://www.tindie.com/products/nsayer/gps-disciplined-ocxo/

It has a choice of four output frequencies, DIP switch selected
and one of the options is 100kHz which would be ideal I think
for an LF receiver.

--
Paul Nicholson
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