[Elecraft] K3 - Volume loss through filter???

[Al Dynarski]

I recently installed the sub-receiver in my K3 and when comparing the filter performance between the two I realized that I have a
problem with one of the filters in the main receiver.  All filters are 8-pole and each receiver has a 2.8khz, 1.8khz and 250hz
filter.  The filter configuration is exactly the same for both receivers.  

 

Listening to the sub-receiver and narrowing with the Width control I can hear the change as I pass from filter to filter and the
volume stays the same for each filter.  However on the main receiver as I pass from to 2.8khz  to the 1.8khz, the volume drops by
about 2/3 and as I pass from the 1.8khz to the 250hz, the volume returns to the same level as the 2.8khz filter.  I suspect that
either the 1.8khz filter has a problem or I may have a problem with dirty contacts.

 

Before I open up the radio and try swapping the 1.8khz filters to see if the problem follows the filter, I wanted to be sure I was
not missing some other cause or configuration issue. Any comments would be appreciated.

 

Thanks,

Al  W7SYK