[Elecraft] K2 Loss of functions on 20M & 17M bands

[Ray Spreadbury]

Hi Elecrafters

 

The K2  (# 4099) has the 100W amplifier and external tuner. It appears to
behave normally in all modes on all bands except 20M & 17M.

 

The K2 has lost all receive sensitivity on both the 20M & 17M bands (no
signals can be heard). 

 

In addition, it will not transmit on these two bands and has a very high SWR
into a 50ohm dummy load on these bands. 

 

Bypassing the external tuner does not improve the situation even when
feeding into the dummy load, so I assume the problem is within the K2 rather
than the external tuner.

 

I am not sure if these symptoms point to a problem(s) in either the
band-pass and low-pass filters?

 

Any ideas of what I should be checking please?

 

Cheers

Ray G3XLG