:It's hard to read - I can't read the resistances any better than you can. But, my guess would be the same. Note that the resistances are specified hot; they would be less when cold.
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:If the field coil on just one speaker is bad, no sense replacing both, right?
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:Power supply chokes are usually specified by their current rating and there resistance. Your replacement should have a current rating of at least the maximum current through the coil. You can figure that by adding up the plate currents, etc., from a tube manual.
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:The coil resistance should be equal to the original. You can pad it with an extra power resistor if necessary. Figure power rating by I^2R and doubling for safety. After replacement, check the B+ voltages, especially since there is some uncertainty in reading the schematic. Trim the dropping resistor if necessary.
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:The inductance of the choke isn't critical.
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:You could forget the choke for the time being and just replace the field coil with a power resistor, and jack up the value of filter caps #93, #57, and #40 by 50-100%. That likely could give you acceptable hum.
:Doug
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::All right, guys: I will give up on the idea of repair. Now, the next question is can any of you tell me the resistance measurements for the field coils in this radio? I have enlarged the schematic and it looks to me that the 12" speaker field coil is 1100 ohms and the 10" is 4050 ohms. Does anyone have a better copy to verify this? I have read about the problem of increased hum when the EM speaker is replaced with a PM one due to the loss of the choke function of the field coil if one simply puts a resistor in it's place. So I'm assuming a better option would be to use a choke and a resistor (if needed to get the right resistance. Can anyone recommend a specific choke either from radio daze or AES? Thanks a lot. Mark from Kalamazoo