Fender 65 Twin Reverb Reissue - No Reverb

[ratlordfx]

Hi there,

New to the forums, so I hope everybody is well

I am having an issue with a Fender Twin Reissue that has been worked on by somebody else, and very badly at that...

I found resistors R15 and R22 piggybacked across the old open resistors. Also R28 was open, but not replaced, so I fixed all of those. Still no reverb.

I had a replacement tank for this, but swapping them I still get nothing. Same with the reverb transformer (which I have a few of).

On the scope, I see my 1khz 30mv signal at the input, and all the way up to the tank. Then nothing on the other side. I can shake the tank and get signal on the output, but it seems like there is no signal going into the tank, but i have signal at TP10.

This amp has several problems, but this is the main issue, and I am stumped, because I know my tanks are good.

Here is a link to the schematic and layout, let me know if youve ever dealt with an issue like this before

http://www.ampwares.com/schematics/6..._@20manual.pdf

Thanks,
Jason 'Rat Lord" Richardson

[Chuck H]

I can shake the tank and get signal on the output,..

...i have signal at TP10.

...I know my tanks are good.

Two considerations. First, are you testing signal for TP10 at the chassis jack or at the tank itself. If you're testing at the chassis then the reverb tank input cable is still suspect. Then the only thing you haven't tested is the tank because you assume it's good. But the input transducer in the tank being bad is what the symptoms indicate. In fairness to yourself you need to test that.

[ratlordfx]

Two considerations. First, are you testing signal for TP10 at the chassis jack or at the tank itself. If you're testing at the chassis then the reverb tank input cable is still suspect. Then the only thing you haven't tested is the tank because you assume it's good. But the input transducer in the tank being bad is what the symptoms indicate. In fairness to yourself you need to test that.

Hey Chuck,

Thanks for the input. I tested TP10 directly on the circuit board. I figured out the problem tho and you guys arent gonna believe this... The jacks on the chassis are reversed, either from the factory or the guy who fixed this before me. I was wondering why switching tanks wasn't doing the trick. I had signal going in, and spring noise coming out.

Anyways if anybody else notices this on this model let me know. Otherwise im going to chalk this one off as a repairmans mistake... hard to believe they would do that from the factory... but this is the reissue

Thanks again!!

[ratlordfx]

Hey Chuck,

Thanks for the input. I tested TP10 directly on the circuit board. I figured out the problem tho and you guys arent gonna believe this... The jacks on the chassis are reversed, either from the factory or the guy who fixed this before me. I was wondering why switching tanks wasn't doing the trick. I had signal going in, and spring noise coming out.

Anyways if anybody else notices this on this model let me know. Otherwise im going to chalk this one off as a repairmans mistake... hard to believe they would do that from the factory... but this is the reissue

Thanks again!!