[Elecraft] WWV tones and CW reverse?

[Bill Coleman]

On Dec 26, 2004, at 9:13 PM, JAKidz wrote:

> When a K2 is set to zerobeat the 10 Mhz WWV carrier, should the
> pitch of the WWV tones not change when toggling between CW and CW
> reverse in CW mode or between USB and LSB as toggled by CW reverse?

There may be a slight change. It is hard to eliminate this entirely.

> And,
> when the pitch does not change, the difference between the frequency
> readout (10000.14) and 10000.00 is how much lower I need to set C22?

I believe this is entirely dependent on the BFO settings for CW and CW 
R (or USB and LSB).

This is one of my tricks for trying to get USB and LSB to sound the 
same. (and for CW and CW R) I'll use another receiver to listen to a 
strong AM signal (with an AM detector). Then I'll tune the K2 with LSB 
until it sounds the same pitch, and switch to USB. If there is a 
difference in sound, I bump the USB BFO setting one notch either way 
until it is the same. (This is done after calibrating with Spectrogram 
or its equivalent) Usually the initial calibration is close, but this 
helps to get it dead on (well, at least really close).

Note that, because of the asymmetrical shape of the SSB filter (and to 
a lessor extent, the CW filter, depending on how wide it is set), the 
"color" of the background noise in USB and LSB will be different, even 
when the BFOs are dead on.

Because of the slight variability in frequency steps in the K2, the 
frequency response in each sideband can be off by about 20 Hz.

I've never understood the obsession with exact frequency readouts with 
the K2. Even if you get C22 exactly on 4.0 MHz, the K2 calibration may 
vary a bit. If you are within 200 Hz on all bands, I wouldn't worry 
about it.


Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net
Quote: "Not within a thousand years will man ever fly!"
             -- Wilbur Wright, 1901