[Elecraft] K2 Transmitter and KAT2 failures

[Damon - KC5CQW]

Below is some of the text that I sent to Gary. 
Basically, if I use the KAT2 to tune my 40m attic dipole the PA finals will
short out. 
I haven't tryied to tune any other antennas because I don't want to pay for
any more PA kits ($18.50 'ish each time I tune up).  
Also, CW is un-usable above 80m and no CW output on 10m (SSB and "tune"
yield 8.5W)

See text below...

73, Damon KC5CQW

Copied text from support email:

On 40m-10m when I release the CW key or mic PTT in CW mode, the moment it is
released I get a power spike resulting in a HiCur warning.
On 12m and 10m I have no output during key down; Only the power spike. (CW
only, SSB is fine)
If the tune button is activated, The radio will give about 11w Max on 12m
and 8.5w on 10m.
All other bands yield 12-15W max.


At the time of the last PA meltdown, I was able to tune my 40m dipole on 80,
40 and 10m; It failed at 30m.
There seems to be no rhyme or reason as to when a failure will occur. It has
happened at different frequencies.
I am reluctant to use the KAT2 except in bypass from this point on. 
I don't seem to have any problems with my MFJ-969 Versa Tuner II. 

During some KAT2 troubleshooting, I found that the voltage on pin 1 of U4
was about 2.5VDC (3-4V spec at 5W) with a leg of R6 lifted.
Perhaps I'm not having a mechanical short on the LC board. Maybe the
SWR/Power bridge is sending the wrong data.
If I tune up on 10m into my dummy load, the K2 reports a 2.1:1 SWR. My
MFJ-969 read 1.05:1

The best I can tell, everything seems to be fine on the SSB modes. I can't
help but think however, if a problem in CW if occurring that I may have some
distortion on SSB.



-----
Damon Wascom KC5CQW
Elecraft K2 #:6351
Build: 12/28/07-01/01/08


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