KPA100 Problem still exists, but some new measurements
Posted by
GS-3 on
Feb 04, 2005; 1:42pm
URL: http://elecraft.85.s1.nabble.com/KPA100-Problem-still-exists-but-some-new-measurements-tp374307.html
Hi there,
I'm still on page 43 in the process and I have now narrowed the problem area. You remember, I measured a negative voltage of 0.15V on J3+.
Now: I removed Z1 and found the voltage measured at the collectors of Qs 1 and 2 to be -0.4V (J3+ is ok now). I don't know where it could come from. Shorting the collectors to ground via 1k resistor it takes 3 seconds to eliminate the voltage. I measure 0V. Removing the resistor it takes abt. 20 seconds for the voltage to go to -0.4V again.
T2-4,5 are ok. The base of the transistors are ok, 0V. The emitters also, 0V. The body of T2 also has -0.4V.
Any idea and testing procedures appreciated!
Kind regards
Gerhard Schwanz
DH3FAW
mailto:
[hidden email]
http://www.gs-personal.de_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com