Mace reverb hum

[dlb]

I appreciate the earlier help with getting my old Mace amp up and running.

Somewhere along its history the reverb tank was removed. I purchased a new 4EB2C1B tank and installed. There is a very prevalent hum when the reverb control is barely increased from 0.

The input and output cables are new although not the original type.

Is there a certain filter capacitor I should be looking at?

Thanks again for the help!

[oc disorder]

Try rotating it 180 deg If the output of the tank transducer is sitting directly under the power transformer it will hum.

[dlb]

Damn... that did it! Thanks!

The only small issue now is when the reverb control is > ~75% I get a weird squeal type sound. Anything less than 75% is good.

Thanks again!

[oc disorder]

Maybe its induced feedback .. move the speaker wires as far away from the reverb/rev. wires as possible.Also try grounding the speaker frames.
If the shielding around the reverb wires is not good could cause it too.