Re: Any SS foks here : 15003 readings



Those two transistors (cited in the OP) are very nearly in parallel.
So any results are questionable if in-circuit. A simple diode tester
may not be enough to tell one from the other. Those resistors are only
5 ohms.


Blown transistors usually go all open, or more often dead short. Dead shorts are easy to spot with the meter, you see 0 ohms. An open here with the parallel transistors is a little harder to identify. If the circuit seems to operate, se if one transistor isn't getting warm. Or see if there is any voltage drop across its emitter resistor. Exercise care that you don't short something when fumbling with test leads, I tend to blow stuff up worse with this mistake. Tube circuits are more forgiving, and circuit nodes are further apart anyway. Another issue is that some solid state stuff might degrade a little from abuse, and die days later (when you think you had it fixed...).

Check both sides of a complementary pair (the NPNs and the PNPs here). One might be shorted, and the other side blown open.
.

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