I've been trying to fix my home intercom system. It fails by blowing fuses so I figured one or more components had failed short. Boy was I wrong lots of shorted components including several transistors.
It's pretty easy to test a bipolar transistor with a DVM in diode test mode. You don't need to know whether its NPN or PNP so it's pretty quick.
Quick test to see if a transistor is bad. This works for most NPN and PNP transistors that have failed with a short.