[Elecraft] K2 CAL_FIL and the BFO

[Stephen Rector]

I'm new to the list, with a couple of questions on the K2. My s/n 6770  
has been running for about a week: this weekend put in the KSSB2,  
KDSP2 and KNB2. When I select from the four CW xtal filter bandwidths,  
I get a slightly different pitch on the received CW station.

Qusetion 1: Is that pitch change directly due to the offset I have  
dialed in during the filter calibration?

The circuit changes the bandwidth of the Cohn crystal filter and, at  
the same time, I dial in an offset to center that new passband to my  
desired pitch. So, I'm confused why the pitch changes - maybe it's  
just calibration error because the tuning step is coarser than my ear.

Question 2 is an observation: CW mode is LSB all the way to 17 meters,  
then USB from 15M up. This is normal, right? On previous  
(upconverting) radios it's always been USB from 20M up, so this  
surprised me.

Thanks for any help with these...

73,

Steve NU7B