Mike Andrews wrote:
hillbilly3302 wrote:

Hi ED, thanks for the response.... yes its a Mech. hum, I have never
put it on the air. I bought it from an estate and when I fired it up I
noticed the hum when I turned on the HV switch.... it has the solid
state recitifer replacements and 4 brand new 811's I doubt I ever use it
and I'de like to get my $250.00 back out of it...lol


Any chance it's just the power transformer laminations vibrating?

I'd worry more if it didn't hum.

-Bill