[time-nuts] Symmetricom Syncserver S300

[Bob Darlington]

Guys, I have a broken Syncserver S300.  OCXO, gps, 60kHz receiver
internal.  No Rb or anything special.  It's been broken since 2015.  It was
fine till I power cycled the thing, but that's the way it goes with .gov
surplus stuff sometimes.  It ran for years before that.

Symptom: 4 red front panel lights, nothing on the serial port (front serial
port, don't know if there is another inside), and during boot the VFD on
front spins the hourglass.  It gets to booting or loading OS and eventually
just freezes.

Digging through the archives I see a similar issue described and that
system seems to have been resolved by noticing high frequency ripple on at
least one of the DC power supply lines and replacement of a capacitor.
Well, I saw that, and I found a bulging cap, and replaced it.  And sure,
maybe the ripple is better but it's not perfect and it didn't fix the
problem.  There's a lot of trough hole electrolytics in the PSU.  The one I
changed required desoldering of a daughter board that was bolted to some
other bits.  A real pain.  15 minute "fix", but a pain.   I don't see any
of the others bulging but that doesn't mean they're all good.  I don't know
if the ripple I see is even coming from the PSU or the main board, or if
it's even a problem.

There was some speculation about CF card corruption. I didn't chase that
down.

I'm done!

If anybody in the USA is interested in continuing on this repair project, I
will give you the unit for the cost of shipping.  I don't know what that
will be, but I assume under $50.  The unit has rack ears and cosmetically
is a 9.5 out of 10.   Talking to TVB, his suggestion was to test with an
external clean power supply to rule that out.

In the very least it's a pretty nice 1U rack enclosure.

Please, ping me direct and I'll let the list know it's spoken for.  I'll
let the next owner ask for help! I'll image the CF cards to keep around
just in case.  Again, USA only.  Somehow shipping clocks will be under ITAR
rules and I don't wanna go there.

-Bob N3XKB