[TenTec] Centurion Bias Transistor Follow on post

[Michael Marx]

Guys,

I just posted a message about my Centurion with a bias problem.  As I stated I replaced the bias transistor which did not fix the problem.  Here is something interesting that I don’t understand.  I bought 5 of them from Mouser.  When I measure the transistor junctions with my Fluke 87 meter in the diode function, one junction seems normal as it measures .5 V in one direction and open in the other.  Normal, right? Now the other junction measures open in both directions.  It also measures open in ohmmeter mode.  Could I have bought 5 bad transistors?  Is that even possible?  What am I doing wrong in testing these transistors?  They are just an NPN bipolar transistor, right?  FYI it is an MJ15001G by ON.  This is exactly what Ten Tec sent a few years ago when I had to replace the transistor.  

Very confused.

73
Mike WB0SND


Michael Marx
sndtubes at vacuumtubes.com
636-939-9190

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