[AMRadio] : BC 610 needing POWER 220VAC

Brian Sherrod ars.w5ami at gmail.com
Sat Apr 8 11:16:30 EDT 2006

On Saturday 08 April 2006 9:16 am, James M. Walker wrote:
> The BC-610, does not operate properly, when the front panel
> switch is in "protect" or "tune" mode, if you are on AM. Bias
> voltages change all around as the "tune/protect" position switches
> in a series dropping resistor to the 115 VAC main input.
I may be wrong, however I thought that ONLY the HV plate voltage circuit was 
reduced via the wire wound power resistor inline with the primary side when 
HV protect is on.  Seems that dropped the primary voltage to about 70 volts.  
The bias, filament, etc. stay the same on mine, and should!  

Still doesn't mean you can operate phone like this without adjusting the bias 
to compensate on the modulator's...  I have done this using the winding of a 
large 12v transformer in series instead of the stock resistor in the 610.  Of 
course there is some change needed in the bias to compensate.

Brian / w5ami

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