[Elecraft] K2 problem: no tx output on 15 and 17m

[Don Wilhelm]

Nick,

My best guess is that something has happened in the 15/17 meter bandpass 
filter.  You could verify that guess by doing a check of a couple points 
in the Transmit Signal Tracing section of Appendix A in the manual.   
Use the RF Probe or oscilloscope with a 10X probe. You can start on page 
14.  The two points of interest are the Buffer Output and the Bandpass 
Filter Output.  Of course, you would set the K2 to 15 or 17 meters 
rather than 40 meters as suggested in the manual.  If you have a good 
amplitude signal at the Buffer Output, but little or none at the 
Bandpass Filter Output, you have confirmed that the bandpass filter is 
the problem.

If you are also getting HiCur messages, the most likely problem area is 
the Low Pass Filter rather than the Bandpass Filter.

The first thing to check is soldering.  An unsoldered or poorly solder 
connection can work fine for a long time with only mechanical contact, 
but one day it develops enough oxidation to cause a problem.

73,
Don W3FPR

On 4/30/2014 12:18 PM, Nick Henwood wrote:
> Any advice please?   My K2 suddenly lost tx output on 15 and 17 (actually still a tiny amount - less than a watt). Still receiving OK on those bands. I removed the 100w amp and the problem relates to the K2 barefoot. There is common circuitry on these bands - any suggestions where to start checking pl? The K2 is still working OK on all other bands.
>