K2 SN 6059 no SSB transmit
Folks, I’m trying to get a newly built SSB board working on my K2. K2 works on
CW per Don’s set up and testing last year. I’m working through the SSB
alignment on the SSB manual. Stopped on page 19 at “Fine Carrier Balance
Adjustment” where it asks that I verify K2 is transmitting when PTT is pushed.
K2 is set for 5 watts power, SSB /LSB mode, SSBA is 3, SSBC is 2-1, FL1 is
selected. My wattmeter shows no output when I push PTT. Wattmeter shows about
5 watts when I push “Tune.” Checking for component orientation, proper
component, cold solder joints, solder bridges, etc. all looked good. Checking
the DC voltage levels on the troubleshooting chart revealed some discrepancies:
On receive:
U1-U5 all pins looked ok except :
U1-6 was 5.5 v., should be 5.1 v. U1-26 was .24 v., should be 0.0
v.
On transmit:
U1-U5 all pins looked ok except :
U1-10 was 2.8 v., should be 3.1 v. U1-13 was 5.75 v., should be 5.9 v.
U1-14 was 5.6 V., should be 5.9 v. U1-16 was 3.0 v., should be 5.4 v.
U1-17 was 4.1 v., should be 5.6 v. U1-28 was 5.4 v., should be 2.4 v.
U2-8 was 3.0 v., should be 5.4 v.
All the diode voltages looked to be OK.
I am at a loss as to where to look next and what exactly to look for, and would
greatly appreciate any and all comments and inputs. Thank you for your
attention.
Bob Hoey KI4RSE
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html