[Elecraft] K2 BFO problem

[Ken Mohler]

You were right, Don, as usual.  The problem was an unsoldered point on the
control board. I was looking on the wrong board the whole time. All tests
and adjustments on Part II are complete and I'm moving forward.  Thanks for
all the help!

Ken
K0WKM

-----Original Message-----
From: Don Wilhelm [mailto:w3fpr at embarqmail.com] 
Sent: Monday, July 19, 2010 9:06 AM
To: Ken Mohler
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] K2 BFO problem

Ken,

You are likely chasing a bad solder connection - things that change by 
themselves is usually an indication of a solder problem.
You are getting close if it was the Q24 drain voltage changing.  Check 
RF Board R98, and then go to the Control Board and check the components 
shown on the Control Board schematic area marked "ALC" (at the top of 
the page).  Double-check the position of the components soldered on the 
back of the board.   When in CAL FCTR, tapping BAND+ should result in a 
high voltage on the VALC line, and tapping BAND-, it should drop to 
zero.  Don't forget to check the connectors between the Control Board 
and the RF Board.

73,
Don W3FPR