[time-nuts] HP-5065a bought and finally working!

J. L. Trantham jltran at att.net
Wed Aug 22 12:22:27 UTC 2012


Congrats on getting the 5065A up and operational.  Make sure the A11 Board
(Temperature Controller) is all OK.  Failure there can destroy the A12 RVFR
Assembly.  There is a lot of 'expertise' on the list for this unit.

What is the serial number of your unit and what is the part number of the
manual you have?

I have a couple of manuals and I may also have the 'change sheets' that
updates the manual to your serial number.  It may take me a while to chase
that down but if I have the 'change sheets', I can scan them and send them
to you.

I have not heard of anyone 'disciplining' the 5065A by GPS, other than by
hand from week to week.  However, the 105B has a built in connection on the
back that is great for that purpose (negative slope, as I recall) and I have
done that using a Brooks Shera controller board and the 1 PPS from my TBolt.
It works quite well.


-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Edgardo Molina
Sent: Wednesday, August 22, 2012 12:22 AM
To: time-nuts at febo.com
Subject: [time-nuts] HP-5065a bought and finally working!

Dear Group,

I wish you well.

Do you recall a message and thread about a month ago with my concerns about
buying a used / unknown condition HP-5065a rubidium frequency standard? I
bit the bullet and bought it. Almost mint condition (cosmetically speaking)
and with several operational issues. 

Well, It took me several weeks to put it back to work. Several capacitors on
several boards along with a couple of transistors and an IC were replaced.
After that any being bored by the yellow light, it finally came off to allow
a beautiful green lock condition light. I went through the necessary steps
to tune it and calibrate it. Now, as I have been told recently. "You have
been bitten by the Time Nuts bug." I am not complaining at all.

Now the technical issues if you kindly allow:

a. Does anybody have an HP-5065a manual for the latest versions? Mine (which
I downloaded from the Internet) is intended for earlier versions. It seems I
have one of the last produced units. I would kindly appreciate any help on
this and I am willing to pay for time and expenses to anybody who could
help. During the repair process I found several differences in the earlier
versions design and had to figure out hoy mine works.

b. Is it possible to build a GPSDRb? I would like to know if it is
reasonable to pursue the goal to discipline the 5065a with a TB which I also
got recently. 

c. I am waiting for the delivery of a recent purchase. An HP-59309a Digital
Clock to go with the HP 5065a. How I wish I could find the optional LED
integrated optional clock and 1PPS output. Is my purchase a good match for
the 5065a? Any other suggestions to drive a clock?

d. I am waiting also for de delivery of an HP-105b mint condition quartz
frequency standard. Would a second 59309a make sense to use it with this
quartz standard? Or just saving it for a Cesium? Anybody willing to sell a
spare, dust gathering, clean unit to me?

e. Any suggestions for software of lab equipment to measure my experiments
like AD, jitter, phase comparisons, etc?

While I wait I am doing some experiments with a FE Rb standard to discipline
an Adret synthesiser to output 32.768 KHz to directly drive a Nixie clock
kit I just finished building.

Your comments are surely welcome. Thank you!

Kind regards,

Edgardo Molina

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