How to Stop High-Pitched Humming from 70s TV's?

[idiotbox]

I've got a couple B&W TV's from the 1970s that as soon as I turn them on, emit a painfully high pitched and loud hum. They are a 1975 Quasar and a JVC Model 3240 Videosphere. Is this normal and is there anything I can do to stop/reduce the hum? I have the ears of a dog so maybe others haven't noticed this. It's gotten to the point where I can't be in the same room as the TVs because it is so uncomfortable (which really takes the fun out of putting them to use). I have no clue what exactly causes the hum, but even with the volume all the way down the hum doesn't change. Thanks in advance.