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Old 23rd Apr 2019, 8:56 pm   #1
Steve G4WCS
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Join Date: Sep 2004
Location: Preston, Lancashire, UK.
Posts: 260
Default RF power transistor testing

Picked this bargain/money pit up for less than the price of the heatsink. Someones gone to a lot of thought with this then spoilt it by tacking bits on like an afterthought
I'm going to give it a full rebuild. I don't like the rats nest biasing circuits, and I'm thinking of using the LM723 bias circuit as per the Motorola application note.

I'm hoping the power transistors aren't fried but I'm working on the assumption that they are.
What's the recommended way to test them, just checking for shorts/open circuits and checking the diode junctions, any precautions etc?

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