what is the reading of a multi tester in a good or damage transistors?

Answer 1

The two junctions (base-emitter and base-collector) are like two diodes and each can be checked with a multimeter to see that it conducts one way and not the other.

Using an analogue meter switch it to one of the lower resistance ranges.
I f you want to use a digital meter it will need to have a dedicated diode range because the normal resistance ranges don't present sufficient voltage at the test leads to turn a diode junction on.

Do a search on Google for basic transistor tests, or something similar.

(I think it's about time I wrote up a simple article with diagrams to add to my web site.)