[Elecraft] PA transistors
Vic Rosenthal
[email protected]
Wed Nov 6 14:33:00 2002
I have four 2SC2879 transistors, such as are used in the KPA100 PA. When I
measure the forward voltage drop of the emitter-base jucnctions I get:
#1: 0.592v
#2: 0 v
#3: no continuity
#4: no continuity
question 1: I presume this means that only #1 is good?
question 2: Is it necessary to replace both transistors with a matched pair in a
push-pull circuit like the KPA100?
question 3: Assuming #3 and #4 are bad, what conditions cause this kind of
failure?
No, they're not from my KPA, but from my %!$@% high-power final. The problems
I've had with this make me want to go back to 100 watts maximum!
Vic K2VCO