reverb hum in a princeton chorus,transistor amp

[Joe Buckley]

I have a Fender princeton chorus amplifier ,a transistor amp with two speakers. it has a good clean sound and it suits my purposes well.

Recently there is a humming sound that seems to be linked with the amplifier's reverb. My first guess is that something needs cleaning or that there is a grounding problem. My electronic skills are slim and electricity is not something to play with.

Having said that does anyone have any ideas ,simple and safe ideas, about how i could fix this problem.

I also have an old gregory mark 11 tube amplifier that lost a great deal of it's volume. The tubes are ancient and I think that is the first thing that may remedy the problem. I know it is not a classy old fender amp but It is mine and the tremelo on it sounds pretty cool when everything is working ok.

Any bright ideas and helpful hints would be apreciated.

With best wishes

Joe Buckley