[time-nuts] schematics for a HP117a please

J. Forster jfor at quik.com
Sat May 1 17:02:49 UTC 2010


Have you tried Dave at Artek Media?

A couple of things on the 117A:

The antenna is a roughly 1 meter diameter loop, but has a very frequency
selective pre-amp built in. Early versions used two Nuvistors and a 60 KHz
mechanical filter. Later versions used FETs I think. The amp in the unit
also uses three Nuvistors. These devices are getting scarce and expensive.

The coax between thr receiver and antenna has DC on it to power the loop
preamp.

The paper for the stripchart is getting hard to find also.

FWIW,

-John

==============




> Just picked up 2 units at a flea market today.
> Would like to fire them up without smoke. :-)
> Would appreciate schematics if the are out there.
> My search so far is 0
> Thanks
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