[Elecraft] K2 Failure

[Dauer, Edward]

More on the defunct K2:  I measured the DC voltage on both sides of F1, 
the self-resetting fuse.  With the power switch “off” the voltage is 13.8. 
 With it on, the voltage is essentially zero on both sides of F1.  
Measured the resistance to ground at the collector of Q7 - it’s about 2 
ohms, not the >500 it should be.  But that doesn’t mean that Q7 or Q8 is 
the culprit.  A short anywhere on the DC line could cause that reading 
anywhere else, yes?  So, what’s the best procedure to isolate the problem 
— I removed the KNB2 and the KAF2; no change.  Tomorrow, in the cold gray 
light of dawn, I will pull the front panel board and the control board off 
the RF board, to see if that narrows it down.  Tonight, I will just have 
another glass of wine.  That should help.

Anyone know if F1 has a reset time of just under a second?  If so, then 
the “popping” noise may be F1 trying to reset itself.  Which doesn’t help 
locate the downstream problem, of course.  But it would strongly suggest a 
DC short somewhere rather than some configuration glitch, yes?

Ted, KN1CBR