Philco 42-321 volume issue

[Kamakiri]

Which would you classify as the third?

[old_coot88]

For the heck of it I would try this (assuming the control element is open at the bottom end)..

First verify solid continuity (zero ohms) from bottom lug of vol control to ground (the common ground buss, not chassis).

Using a couple of clip leads, try subbing a number of random value resistors, say 100 ohms to 100K ohms, between the middle lug of vol control, and the bottom (ground) lug. Sub them one at a time. You should be able to find some value that'll produce usable control action, though it'll be very nonlinear.