transistor troubleshooting

[trem]

I only have a basic understanding of tube guitar amps. My son asked me to fix a SS power amp. Is there a reliable way to test a transistor, out of the circuit, with a DMM...? It is one of these, with a double Emitter lead.
2SC2290 pdf, 2SC2290 description, 2SC2290 datasheets, 2SC2290 view ::: ALLDATASHEET :::
Thank You

[oc disorder]

This page should help from "The Electronics Club"
Transistors

1. Testing with a multimeter
Use a multimeter or a simple tester (battery, resistor and LED) to check each pair of leads for conduction. Set a digital multimeter to diode test and an analogue multimeter to a low resistance range.
Test each pair of leads both ways (six tests in total):

The base-emitter (BE) junction should behave like a diode and conduct one way only.
The base-collector (BC) junction should behave like a diode and conduct one way only.
The collector-emitter (CE) should not conduct either way.
The diagram shows how the junctions behave in an NPN transistor. The diodes are reversed in a PNP transistor but the same test procedure can be used.

[trem]

OCD....
That is what I need. I did not have a "good" transistor to copmare it to, so I was not sure what the diode function on my DMM was telling me.
The transistor is bad, I have ordered a new one.
Thank You