[Reece]

First, wiggle all the tubes while the radio's playing. Could have a bad contact that needs to be cleaned.

On the volume control are three terminals close together. The center one is the rotor. With the radio on, take a piece of insulated wire a few feet long and touch one end of it to the center terminal. You should get a loud hum which tells you the audio amplifier circuit is working. If no hum, there's trouble in the audio amp or output transformer.

If you got a loud hum, then looking at the control from the back, with the terminals facing upwards, the terminal to the right of the center one is the high side. Clip a test lead from the center to the high side and play the radio. If the amplifier was good, and the control was bad, the set should play with maximum blasting volume now (just for a few seconds before you turn it off!) If no change in volume, the trouble lies elsewhere, and we can go from there.

Reece