73 Deluxe Reverb hums when rvrb turned up

[Shakespeare]

I've got a 1973 Deluxe Reverb that hums when the reverb knob is turned up. The more I turn up the reverb, the louder the hum.

Reverb does work.....but adds hum.

Any ideas?

[Amp Kat]

Could be a cou[ple of things. The filter cap at that node,the recovery tube or your cables may be to close to the speaker and need to be rerouted or shielded better.