[Elecraft] K2 Frequency accuracy by band

[jeff_elecraft at burnshome.org]

I borrowed an IFR FM/AM-1200s service monitor from a friend for a project I
was working on. While I had it I decided to check the frequency accuracy of
my radios. I thought my K2 was 60 Hz high and quick check confirmed this.

I then used the service monitor to adjust the 4MHz crystal, and ran CAL PLL.

I checked the frequency accuracy on each band using the following procedure.
I set the frequency on the service monitor to the center of each band, and
injected that signal into the radio. In CW mode I used the spot tone to
match the incoming signal as close as possible. I then transmitted a low
power signal back into the service monitor, and adjusted the transmit
frequency until the frequency deviation meter indicated zero deviation. The
difference of the service monitor setting and the radio frequency display
was then noted.

The results were:

Set Freq. (MHz)   Error (Hz)
        1.9       -10
        3.75	-10
        7.15	-30
       10.1       -40
       14.15	-60
       21.2	     -110
       24.93     -130
       28.5	     -140

Testing to WWV at 10MHz gave a +10 Hz error. Testing to WWV at 15MHz gave an
error of -10 Hz. These do not quite agree with the test using the service
monitor. 

Has anyone else measured the frequency deviation of a K2 per band? Are these
errors normal?

I also ran this test on my Omni VI. This brings up another question that I
will pose in a separate message. 

By the way, my friend used this service monitor professionally, but has not
had it calibrated since he retired more than ten years ago. 

Jeff Burns
AD9T