A while ago I bought three lovely 5M4's from Trade Me - all restored quite easily apart from the volume. They turn down fine but move the volume control clockwise just a little bit & the sound is very loud. All three radios work like this - I wish I had paid more attention to this before I broke out the soldering iron...
On two of the radios I replaced the volume controls - they were intermittent & a squirt of contact cleaner didn't fix it. (Yes I used log pots)
They all have the resistor network across the speaker & connected to the cold end of the volume control too. I replaced them just to be on the safe side - I used the existing values 'cos this modification isn't on the circuit diagram.
Any ideas on taming these beasties ,please?
Also may I take this time to thank Mr. Dunford for his website. This an excellent resource:)
sounds like someone's attempt to add negative feedback to improve the sound. This Mod maybe causing your problem? try restoring the Volume Pot back to the original design to check. Have you checked the 1 Meg volume Pot and made sure its logarithmic.