[time-nuts] About HP10544A

Bruce Griffiths bruce.griffiths at xtra.co.nz
Sun Mar 8 02:11:31 UTC 2009

Tom Van Baak wrote:
>> I have been able to find schematics of the 10544A but not a service manual.
>> Is there a service manual available?
> http://www.leapsecond.com/museum/10544/
> I'll look for something like a service manual. I know I have some
> interesting info in the 10544. When I find it I'll update the page.
> One thing you could do is look at hp op/service manuals of
> instruments (e.g., frequency counters) made in the late 70's
> and see how they integrated the 10544 into their design. This
> will give you hints on both input power and output buffering.
> I know *late* model 5245L counters used the 10544A oscillator.
> Perhaps others in the group can provide other examples and
> then you can head off to the online manual sites and grab the
> info you need from the PDF files.
> /tvb

No 5245 manuals on Agilent site nor the agilent ftp site nor BAMA site.

The HP5370A also used a 10544A as an optional high stability timebase OCXO.
The reference buffer PCB is close to the 10544A socket.
The reference buffer consists of a series string of 3x 1/3 MC10216 ECL
line receivers.
The reference input pin uses a 1k resistor in series with 10pF connected
to the input of the first ECL line receiver.
This buffer is somewhat crude, but nevetheless has adequate performance
for its intended application.


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