[time-nuts] HP5065A revival project, progress report
magnus at rubidium.dyndns.org
Mon Oct 3 21:54:54 UTC 2011
I wanted to bring you an update on the HP5065A revival project.
I have three units, unit A, B and C.
For unit A I have been able to achieve lock, unit B had a PSU failure
and so did unit C. The PSU of unit A is about to fail, but I will fix it up.
I have now done some work on the A15 board of unit B, repaired traces
and replaced 4 caps. It still provides a heavy load which makes the +20V
supply "duck" to 8,70V, as it goes into current limiting. Interestingly
enough this is limited to the PSU board itself. To test this theory I
borrowed the A15 board from the unit A into unit B, and using my
experience of trimming up unit A I was able to get unit B to lock up and
even lit the Continous Operation lamp.
So, now I have both unit A and unit B locking up for me, but I will have
to work more on the A15 assembly for unit B in order to get them
operational at the same time. However, it will be much more rewarding to
work on that board now that I know that it is about the only thing I
need to fix, and I've already come a bit down the road on that one.
Unit C also has the A15 board failure, but it failed even more
spectacular, so I will need to replace the zener diodes as the acid took
one of the zener diode legs with it... :P
First degree cleanup has been started.
I will also need to replace caps on A15 on unit A, as they are about to
fail. However, running shorter batches should be fine for the moment,
especially as I cab down and get additional convection.
Anyway, it is quite rewarding right now. I just couldn't avoid sharing
some of the progress. Hope it doesn't add too much to the noise here.
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