Twin Reverb - reverb issue

[sliberty]

Working on a 1975 Twin Reverb 135. When first turning on the reverb, the wet signal is sputtery, and then over the next few seconds, it stabilizes and sounds fine. Not really familiar with reverb circuits, so I am shooting in the dark here.

I see that there is a 20uF filter cap that serves the reverb driver stage. Could a bad cap there cause this? There is also a 20 uF cap serving the recovery stage, but that same cap serves the trem channel, which is working fine otherwise, so I am thinking that is not the problem.

The amp has had a cap job, but that doesn't mean that it can't have a bad cap. Or am I toally headed in the wrong direction here?

All help appreciated.

Thanks,
Steve

[Firestorm]

Not likely to be the filter cap. Driver tube, maybe; recovery tube, maybe. Try replacing those. Also clean up all the RCA jacks and plugs related to the tank.

[sliberty]

Thanks for the suggestions.

I should have mentioned that I already tried replacing tubes with no benefit.

As for the RCA jacks, I don't think the sputtering would clear itself up after a few seconds if there were a continuity problem due to crud, etc.

[Structo]

I would def check out the tank, make sure the transducers are alright and the springs are connected properly.

[Zippy]

As for the RCA jacks, I don't think the sputtering would clear itself up after a few seconds if there were a continuity problem due to crud, etc.

Maybe not but I, too, have had success in such cases by cleaning and retensioning the RCA jacks.

[sliberty]

Well, it turns out that the .003uF ceramic disc was failing. I moved the leads slightly, and more than just a little of the ceramic material flaked off. I replaced the cap, and all is well now.

Thanks for your help!

Steve