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Sherman Webers Sherman Webers is offline
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Default Cary SLP-90 Help Please

Peter,

Thank you for your input. As it turned out, I did not have B+. After
talking to the techs at Cary Audio, I pulled out the trusty fluke 77 and
reverse engineered a better schematic. In that process, I found that one of
the wires inside of the Cinch connector that plugs into the remote power
transformer box had broken. After soldering it back on, the unit is back
on-line and sounding great again.

Thanks again.

Sherman Webers
"Peter Wieck" wrote in message
oups.com...

Sherman Webers wrote:
Greetings,

I have recently purchased a used Cary SLP-90. The unit worked perfectly
for
the first day I had it and sounded great. No issues whatsoever. I left
the
unit in the Standby mode for about 4 hours yesterday and now it will not
transfer from standby to operate. I seem to be getting 12v, 6.3, B+.


It could be a bad switch or relay if the B+ supply is relay-operated.
That switch (or relay) carries a great deal of voltage with the
consequent arcing when made or broken. I would expect that it would be
a high-wear part. How did you verify that you had B+, by the way?

With the amp UNPLUGGED and COLD, you could go inside and check. If it
is a switch, look for scorch or carbon marks around it. Perhaps
scraping it clean would suffice for the moment. If a relay, does it
unplug? You may be able to replace it as simply as that.

STANDARD WARNING: Lethal voltages exist inside this amp. DO NOT screw
around inside unless you are awake, aware and knowlegable of the
conditions.

Unless you *KNOW* what you are doing, do not try to verify B+ on your
own. If you do. then try to see if B+ gets as far as the switch (or
relay). If B+ does not exist, then check the rectifiers or rectifier
block. This thing uses SS diodes for the purpose. If you get no AC to
the rectifiers, then a transformer (winding) has smoked, unlikely but
possible. Again, if you have already verified B+, most of the above is
redundant. Look at the changeover switch (or relay).

Peter Wieck
Wyncote, PA