[NJARC] Re. Sears guitar amp

[William S Zukowski]

That's "....analog VOM using the diode test range."

Bill
Sent from my iPad

> On Jan 11, 2017, at 16:23, William S Zukowski <n2yeg at optonline.net> wrote:
> 
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> Sounds like a shorted output transistor.
> 
> Is the hum still there with the volume control at minimum?
> 
> If you can determine the output transistors' leads, measure the voltage across the emitter - collector leads of each transistor.  The output transistors act like a voltage divider, so you should measure 1/2 the supply voltage across each transistor.  A shorted emitter-collector will have 0 voltage across it, and the other transistor will have full voltage.  However, if it's a base-emitter or base-collector short this method may not be conclusive.  The best way is to remove at least 2 of the connections and measure the resistance between each junction.  Do this with either an older analog VOM or using the dio
> 
> Hope this helps.
> 
> Bill
> 
> Sent from my iPad
> 
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