[time-nuts] 5061's on ebay - FIXED IT

[J. L. Trantham]

Not being able to suppress my interests for too long, I explored my newly
acquired 5061A this weekend.  

The problem was an oscillation in the A7 assembly, as determined by looking
at the output at A7J6.  

I am not sure what I did to fix it but I removed all connections to the A7
and A8 assemblies, reconnected them, and no joy.

I then removed the A7 assembly, checked the components that have frequently
failed in the past on my other 5061A's, found no problems, loosened all the
mounting screws for the PCB then re-tightened them, cleaned all the
connections, reinstalled it, switched the 'HI' and 'LO' switch back and
forth half a zillion times, left it in 'HI', adjusted the 2nd Harmonic to
'40' on the meter, and, magically, everything worked.

I suspect the problem will be back.  I suspect a 'marginal' connection or a
marginal component in the A7 assembly.  I have some 'parts units' available
for the next time the unit fails.

Nonetheless, it has 'locked' for the past hour with a Beam I of about 13
nAmp, if my calculation is correct (-131.50 mV from the CS tube as connected
to the cable from the tube to A7J1 and as measured with my Fluke 8050A with
a 10 MOhm input resistance), and the output is 'locked' on my scope with
it's trigger coming from my TBolt.

I have ordered new batteries for the Option 02 battery pack although it even
worked with only one 'dead' cell.  I replaced the 'dead' cell with one that
'kinda works' from another old battery pack, and now even the backup battery
pack is working, 'kinda'.

Happy to answer any questions.

Joe

-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of J. L. Trantham
Sent: Wednesday, February 22, 2012 9:25 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] 5061's on ebay

I'll do it.

I work full time and this is my hobby.  So, it may be a while before I get
into it though.

Joe

-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of paul swed
Sent: Wednesday, February 22, 2012 9:22 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5061's on ebay

Interested