Jeff,

I also measure 4.89vdc at these pins so that is OK.  I haven't looked to see
why yet.

Have you built the RF probe and traced the transmitter signals as outlined
starting on page 12 of Appendix E of the owner's manual?  If so what were
your findings?

73,
Charles N3EJS

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Jeff Kinzli
Sent: Friday, February 02, 2007 11:59 PM
To: elecraft@mailman.qth.net
Subject: [Elecraft] Debugging no TX on K2

So I've been debugging as I get time my recently finished K2, and trying
to find out why it's got no output. 

Tonight I traced all of the DC voltage points in the troubleshooting 
guide, and found two anomolies, both of which are connected to one
another.

On pin 7 of U4, and also pin 1 of U5, I get 4.9V, and the manual
says they should be 0V.

My first thought was a solder bridge, but I see none.

U4 is where there's a mod on the bottom side of the board. My thought now
is that while adding that mod, I overheated U4 and opened up a path 
to pin 7 of 5V. 

Does that sound possible/reasonable/likely? Would that also cause my 
"no output" problem? These chips appear to be in the PLL circuit, so it
seems 
if these were fried, I'd have frequency/VFO problems, yes?

Since these two pins connect to each other, and nothing else, I don't see 
any other way for 5V to get in there.

Or, am I chasing another ghost? :)

Thanks for any ideas guys, you have all been very helpful and I really
appreciate it.

Jeff
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