10-30-2018, 08:46 PM
Welcome to the Phorum!
Tubes 24, 35, and 47 all have a 2.5v filament requirment
A 39/44 tube uses 6.3v so it was probably added in there because it sorta looks like a 35 to make a sale easier, I don't think it would work in a 2.5 volt system....just a guess.
If I remember correctly a Model 224 is an exported version of a 24 but I can't locate a schematic. The 52 sticker on the chassis should be a positive ID that its a 52. The tube shield may have come from another set. I doubt if it left the factory that way but who knows...1932 was a rough year for radio sales and they may have made some short cuts.
Others more familiar with these will surely chime in with thoughts. Pictures might help.
update: I see Terry was typing at the same time I was ... he knows a LOT more than I do...
Tubes 24, 35, and 47 all have a 2.5v filament requirment
A 39/44 tube uses 6.3v so it was probably added in there because it sorta looks like a 35 to make a sale easier, I don't think it would work in a 2.5 volt system....just a guess.
If I remember correctly a Model 224 is an exported version of a 24 but I can't locate a schematic. The 52 sticker on the chassis should be a positive ID that its a 52. The tube shield may have come from another set. I doubt if it left the factory that way but who knows...1932 was a rough year for radio sales and they may have made some short cuts.
Others more familiar with these will surely chime in with thoughts. Pictures might help.
update: I see Terry was typing at the same time I was ... he knows a LOT more than I do...
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