[marcapra]

I have a 1928 radio that was just rebuilt, but it still has excessive static. The repairman asked me to tap the tubes to see if that caused loud static, but it didn't. I discovered that touching or turning the volume control knob caused very loud static that continues for awhile even after I stop turning it. Any ideas as to what's wrong? Thanks.

[codefox1]

The control probably needs to be cleaned or replaced. I would suggest you use DeOxit or tuner cleaner. You have to get the stuff into the control for it to work. Then it needs to be rotated back and forth a few times with the power off. Let everything dry out for an hour or two before powering up again.