Peavey Triumph 60 Reverb Problems

Peavey Triumph 60 Reverb Problems

Hello,
I am attempting to repair a Peavey Triumph 60 guitar amplifier. It was
used in the classic series configuration (speaker output of one
amplifier into the guitar (or effects return) input of this one, to
make use of the Triumph's effects. This of course had the classic
effect of screwing it up.

A fuse was replaced before I received this casualty, don't know which
one.

I did replace the 4 main power supply filter caps, which had bulging
rubber plugs. C42, C43, C44, C45

All seems to work fine with the exception of the reverb. It will work
for a while, then disappear. Probing any HV contact, like the output
of the main diodes, or pin 1 of V3, will cause a pop sound and then
the reverb will return. It will work for a while and then disappear
again. Switching standby status will cause fizzes and pops if the
reverb is acting funny, and will be smooth and quiet if the reverb is
normal.

Peavey Triumph 60 Schematics are here.
* w w w .intergate . com /~gander/Electronics/Pages/Electronics%20Hyperlink.htm

Corrections to schematics - The R tap off the OPT ties in on the other
side of R59, and the pre-amp output comes from the other side of R88.

The caps I put in were new, and I did not attempt to form them. The
amp "seemed" to operate better the longer I have been observing it,
but it is still not right.

Could this be a cold solder joint? Should I "re-solder" all
connections in the amp? I have used a wooden stick to probe components
to see if this might affect the reverb. The only change comes when I
touch a metal probe to the HV circuits.

Switching to standby and back again will also revive the 'verb.

I have switched a 12AX7 in the reverb circuit with the power amp (PI?)
circuit to see if that might help. I do not have a spare 12AT7 to
switch out the other side of the reverb circuit.

Any help would be appreciated. I have taken every class in electronics
my JC had to offer, but I don't have any practical experience. Tips on
troubleshooting techniques and evaluating components are very welcome.
I am hoping maybe someone might spot the problem from the above
symptom, or at least point me in the right direction. I would think it
is power supply/capacitance.

Thanks to everyone in the AGA for all you do. This is a wonderful
place to come for advice on guitar amplifiers, and a great place to
seek enlightenment on the current state of U.S. politics.

Dr RaTsTaR - Novice

Re: Peavey Triumph 60 Reverb Problems

Dr RaTsTaR wrote:

> Hello,
> I am attempting to repair a Peavey Triumph 60 guitar amplifier. It was
> used in the classic series configuration (speaker output of one
> amplifier into the guitar (or effects return) input of this one, to
> make use of the Triumph's effects. This of course had the classic
> effect of screwing it up.
>
> A fuse was replaced before I received this casualty, don't know which
> one.
>
> I did replace the 4 main power supply filter caps, which had bulging
> rubber plugs. C42, C43, C44, C45
>
> All seems to work fine with the exception of the reverb. It will work
> for a while, then disappear. Probing any HV contact, like the output
> of the main diodes, or pin 1 of V3, will cause a pop sound and then
> the reverb will return. It will work for a while and then disappear
> again. Switching standby status will cause fizzes and pops if the
> reverb is acting funny, and will be smooth and quiet if the reverb is
> normal.
>
> Peavey Triumph 60 Schematics are here.
> * w w w .intergate . com /~gander/Electronics/Pages/Electronics%20Hyperlink.htm
>
> Corrections to schematics - The R tap off the OPT ties in on the other
> side of R59, and the pre-amp output comes from the other side of R88.
>
> The caps I put in were new, and I did not attempt to form them. The
> amp "seemed" to operate better the longer I have been observing it,
> but it is still not right.
>
> Could this be a cold solder joint? Should I "re-solder" all
> connections in the amp? I have used a wooden stick to probe components
> to see if this might affect the reverb. The only change comes when I
> touch a metal probe to the HV circuits.
>
> Switching to standby and back again will also revive the 'verb.
>
> I have switched a 12AX7 in the reverb circuit with the power amp (PI?)
> circuit to see if that might help. I do not have a spare 12AT7 to
> switch out the other side of the reverb circuit.
>
> Any help would be appreciated. I have taken every class in electronics
> my JC had to offer, but I don't have any practical experience. Tips on
> troubleshooting techniques and evaluating components are very welcome.
> I am hoping maybe someone might spot the problem from the above
> symptom, or at least point me in the right direction. I would think it
> is power supply/capacitance.
>
> Thanks to everyone in the AGA for all you do. This is a wonderful
> place to come for advice on guitar amplifiers, and a great place to
> seek enlightenment on the current state of U.S. politics.
>
> Dr RaTsTaR - Novice

Remove all Molex-type connectors and treat the male pins with Caig D5.

Push the mating connectors on and off the pins five times each.
Pay attention to the wiring inside the footswitch -
a screw up here will cause all kinds of weirdness
inside the amp. (BTDT) A cracked solder joint is
not an impossibility...try flexing the board(s) (while
the amp is on) by pushing downward on them with
your poke stick. Do it at several different places
to make sure you flex the boards in different
directions.

Lord Valve
Founder, HARM (Heavily Armed Rightwing Maniacs)