[ARC5] BC-348-Q Capacitor Testing

[Robert Eleazer]

First thing to do is to check the current drain with the receiver powered up.  I have a BC-348N that had a AC power supply installed exactly per the Surplus Conversion handbook.  Fortunately, the owner did no more than that, even using the ON-Off-MVC- AVC switch as the AC power switch and even leaving the dial light dimming control intact although disconnected.

After confirming that the receiver worked I rebuilt the power supply, removing the dynamotor plate it was using and replacing it with a 1/8 in thick piece of AL.  I added some resistors to the AC line and B+ line to get the B+ down to 200VDC (the Surplus Conversion Handbook has you use a 300V transformer) and added an in-line AC switch to keep from having to use the MVC-AVC switch.  Current drain is about 60 ma and I have left all the caps untouched except for the ones in the power supply.  If your B+ current drain either on an AC supply or the dynamotor is more than 60ma you should look for possible cap leakage.

Wayne
WB5WSV      
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