[TechAssist] Zenith A25B33W

Hello Folks:
     this Zenith set came in dead.  The main fuse was blown.  I replaced
IC3431 ( STR 53041) and it no longer blows the main fuse.  The set still
will not turn on.  I found that the 9V source was 0V . The 9V comes from ICX
3441 ( LM7809) who receives his 13.2V input from Q3404 when it is switched
on.  I have 15V on the emitter of Q3404 but it is not switching on.  Q3402
is supposed to turn on Q3404 when the Microprocessor chip pin 32 supplies 5
volts to it's base.  I don't see any voltage change on the base of Q3402.  I
hate to think that the microprocessor chip is bad.  Any suggestions ???  

Richard J. Bateman, CET, CA. 
Electronics Program Area Coordinator
Amherst Campus 
716-691-0012  EXT - 232
E-MAIL  rjbateman@xxxxxxxxxxxxxxxxxx


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