Fender DRRI reverb problem suspect footswitch please help going crazy!

[Jimijames31]

I have a 65' reissue that was hand wired very cool amp. I have a buzz in the reverb only when the pedal is plugged in and it goes away if the vibro is enged along with the reverb. If I unplug the reverb footswitch its beautiful quiet reverb. I have examined the pedal and all seems good. Have tried everything in the book, swapping tubes around, replacing v3 v4 tubes, replaced power tubes because one looked questionable, pulled the reverb tank out and cleaned the rca contacts, tried different RCA cables. Really hoping someone can help me figure this one out. I want to sell the amp soon but not until the problem is fixed. Below is a video of the problem.

https://youtu.be/dy0Bbp4qirg

[Jazz P Bass]

Which footswitch are you using?

Fender used a shielded cable.

[Jimijames31]

Looks just like this guy

[Jimijames31]

It should be the footswitch that came with the amp. The buzz doesn't sound so bad in the video I posted but believe me it's really annoying in person. Do you think I should try a new foot pedal or is there some way to better insulate the one I have?

[g1]

Make sure the footswitch lead connecting to the reverb is the shielded one, and the vibrato is not shielded. I had one that was labelled backwards and did what yours is doing.

edit: ignore that, I thought this was the pedal with 2 rca connectors at the amp.

[Jimijames31]

I'll crack it open right now. I hope that's it! Thank you so much for responding I have been trying for a week to solve this. It's good to finally get someone's help

[Jimijames31]

Ok ill disregard.

[Jimijames31]

really seems like a grounding issue. Is it possible it is the reverb switch button itself?

[nosaj]

I had one of those that had a problem turned out opening the 1/4 connector the ground solder joint was less than desirable. Reflowing it fixed my issue.

Nosaj

[Jimijames31]

The solder joints look pretty good but the more I think about the problem the more it seems like it must be something like that. There is a slight pop when I turn on the vibro as well. I'm thinking that its all related. I'll go over those joints with a fine tooth comb to see. Thanks for the suggestion.

[TomCarlos]

What Nosaj said.... I bought a Twin Reissue and had a problem with the footswitch - the right angle plug. The center conductor had a bad solder connection. Test the foot switch with a meter... make sure it is working correctly and that you have solid solder joints.

[Tom Phillips]

Make sure the footswitch lead connecting to the reverb is the shielded one, and the vibrato is not shielded. I had one that was labelled backwards and did what yours is doing.

edit: ignore that, I thought this was the pedal with 2 rca connectors at the amp.

I would not ignore that. I'm assuming that the button labeled "Reverb" actually turns the reverb On-OFF. Correct?

Anyway...I have come across more than one factory new Fender dual foot switch that was wired incorrectly at the back of the buttons inside the foot switch. Therefore, anything can happen so we need to check. Open the foot switch and verify that the shielded lead is the one used for the reverb switch. AND that the reverb button is controlling Reverb not Tremolo. There can be mistakes weather the foot switch uses two RCA connectors or one stereo 1/4" connector.

[Jimijames31]

reverb is the side with the shielded cable. There is one questionable joint in the angled 1/4 jack. now im a novice with electrical testing but I set my multi-meter to the lowest ohms and the tested the switch. What should I be getting for a reading? .5?

[TomCarlos]

When the switch is engaged, you should get near "0" ohms. Depending on your meter and test leads, that could be the resistance you are seeing.

Using the lowest resistance setting on your meter, take the test leads and short them together. Look at your meter. If you are seeing any resistance, that is your baseline. Sometimes, you might get .5 ohms. So you would add that to whatever you are measuring. In your case, it looks like .5 ohms is as low as you'll go. If you change the meter setting to a higher range, that .5 ohms probably goes away.

[Tom Phillips]

...If I unplug the reverb footswitch its beautiful quiet reverb...

That tells me that the amp is working properly. I think that something is amis in the foot swich assembly.

Edit: Do you have a spare un-wired stereo 1/4" jack? If so plug it into the foot switch jack on the amp with the barrol removed so that the contacts are exposed and do this test.
1) Short the tip to the sleeve. That should turn the tremolo ON. Does it?
2) Short the ring to the sleeve. That should turn the reverb OFF. Does it?
3) When none of the contacts are shorted the reverb should be working and there should be no excessive background buzz.