please delete, help no longer required.

This Magnavox is from around 1964 or so...appears to be a very early solid state model. May be a shorted electrolytic cap...this is getting to the age where electrolytics start going bad in larger amounts.
If you can disassemble the tuner/preamp assembly out of the console to where you can get some photos of the problem area it would be easier to give advice what it might be.