[ARC5] BC-348 Dynamotors

[Robert Eleazer]

Thanks Bob, for that reassurance.  I thought it unlikely they would have created a logistics nightmare by having two different kinds of dynamotors for functionally interchangeable receivers.

I have two 24V DM-36-D dynamotors for equipping the BC-348-R I have restored and the BC-348-J I have in work.  I also have a 12V DM-34-D dynamotor to be used with my BC-224-F.  I think I recall that the BC-224 dynamotor uses exactly the same filter as that for the 348's, according to the manual.

For that matter, I have three DM-21 dynamotors that would give the proper output voltage for 348's or the 224, with a 12VDC input, but of course some disassembly would be required and I won't do that - and there is no need anyway.

I see no obstruction that would prevent the same dynamotor to be used in all of the 348's, although the J-N-Q lack the lower plate of the other models, they actually seem to have less room below the dynamotor mount due to the plate holding that humongous capacitor.

By the way, on the topic of hacking of Command Sets, the Surplus Conversion Manual VOL III suggests replacing the 12SK7 IF and RF amp tubes with 12SG7 tubes and shunting resistors R-1 and R-22 with resistors and adding a 0.01 mfd cap between ground and pin 5 of the RF tube.  They do not mention anything about modifying the audio stage.  There is a short article in the 1957 edition of the Command Sets book on how to modify a BC-453 for BCB to use as an automobile AM receiver that suggests eliminating the BFO and connecting that tube as the first audio stage.

Wayne