I got an old 1930s Crosley AM radio. It needs to be recapped and a few other things, such as a dial string and new power cord. Anyhow, after chopping off the bad power cord, I applied a temporary cord and the radio does get sound and radio stations. (Along with the hum from the weak filter caps).
This radio has a beautiful old wooden cabinet, so I am going to restore it completely.
Anyhow, someone replaced the old electromagnet (Field coil) speaker with a permanent magnet speaker. But what they did is sort of odd. I know that speaker coil served as a filter choke, in the power supply, on those old radios. What they did, was saw off the rear of the old speaker, and mount it to the chassis, with that magnet loosly sitting on top of the sawed off rear portion of the old speaker.
What I now have, is this large magnet sitting next to the audio output tube, and very close to the power transformer as well. That magnet is quite powerful, in fact I magnetized a screwdriver with it.
My question is whether that magnetism is going to affect that tube, as well as interfere with the power transformer's function?
If this is a problem, how to I determine what size filter choke to buy to replace it? (Or isn't that real critical)? If it's not going to cause any problems, I may likely just leave it as it is, except to apply some sort of adhesive to prevent that magnet from falling off the sawed off steel piece. Because as it sits now, if I set the radio on edge, that magnet will fall off and could smash tubes in the process. I have never seen this sort of thing done.... Very strange!
By the way, the audio output transformer appears to be glued on to the speaker frame, but it is tight, so I am going to just leave it.