learning to test horizontal output transistor - odd readings?

Cartouche

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learning to test horizontal output transistor - odd readings?

I'm trying to test, for practice, these two horizontal output transistors. It's the part# 2SD1938, I believe referred to as a 220 package?

One is new from Bob Roberts, the other I removed from a wg19k7905 I'm attempting to rebuild.

I was under the impression that to test this with a DMM, one places:
1. red to base, blk to emitter = junction drop ~ .7
2. red to base, blk to collector = junction drop ~ .7
3. blk to base, red to emitter = open
4. blk to base, red to collector = open
5. blk to collector, red to emitter = open
6. blk to emitter, red to collector = open

I test the old one, and results are:
1. .07 (way too low, right?)
2. .49 (ok)
3. .07 (should be open, right?)
4. open
5. .52 (ditto)
6. open
I figure, good idea to replace this - 1,3, and 5 say bad transistor.

More importantly, the brand new Bob Roberts one shows:
1. .53 (good)
2. .48 (good)
3. 1.67 (huh?)
4. open (good)
5. 1.78 (huh again?)
6. open (good)

On both transistors, I get readings at 3 and 5 - so am I misunderstanding something about testing these puppies? Or are both transistors be bad?
 
There is an internal resistor connected base-to-emitter in that transistor.

If you use an analog multimeter, B to E one direction is about ten ohms and if you reverse the polarity, it should read 30 to 40 ohms.
 
There is an internal resistor connected base-to-emitter in that transistor.

If you use an analog multimeter, B to E one direction is about ten ohms and if you reverse the polarity, it should read 30 to 40 ohms.
Did you mean a damper diode?
 
Thanks - I'm beginning to see this is a lot like learning French. Lots of rules and lots of exceptions to those rules.

There is an internal resistor connected base-to-emitter in that transistor.

If you use an analog multimeter, B to E one direction is about ten ohms and if you reverse the polarity, it should read 30 to 40 ohms.
 
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