Hi Folks I have a master volume pot on a Polytone amp I have that's getting wonky so I want to replace it. There doesn't seem to be any markings on the pot but I have to admit I didn't take it out of the chassis yet. But I did measure the ohms readings between a outside pole and middle pole with the pot on 10 , and this is what I got. METER set to read 200K and the actual reading I got was 75.0. So the question is what value pot do I need to get to replace the wonky one.? any questions please ask. G.