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A somewhat riskier but faster approach is to take a pair of hemostats and short across base to emitter of first one, then the other final transistor. If both are contributing equally to the output power you'll see the same drop in power either way. Even if one final transistor is totally dead you'll see a drop in power shorting the input of the dead transistor. But if one of them is really not working you'll see the power drop to zero when the good transistor gets the drive removed from it this way.

And if you see more or less the same drop in power doing this to each final, they're both working.

Takes a steady hand. If you accidentally bridge the base to the collector, it won't matter how quickly you draw the tool away. This will surely croak a good final if it happens.

73

[QUOTE="nomadradio, post: 815814, member: 22"] A somewhat riskier but faster approach is to take a pair of hemostats and short across base to emitter of first one, then the other final transistor. If both are contributing equally to the output power you'll see the same drop in power either way. Even if one final transistor is totally dead you'll see a drop in power shorting the input of the dead transistor. But if one of them is really not working you'll see the power drop to zero when the good transistor gets the drive removed from it this way. And if you see more or less the same drop in power doing this to each final, they're both working. Takes a steady hand. If you accidentally bridge the base to the collector, it won't matter how quickly you draw the tool away. This will surely croak a good final if it happens. 73 [/QUOTE]

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