[Elecraft] N6KR's 4 MHz oscillator cal method for the K2

[Don Wilhelm]

John and all,

When using Spectrogram as an aid to determine zero-beat, it is much easier
to observe the transmitted tones than trying to offset from the carrier -
just look on the Spectrogram screen for the frequency of the tones.  They
alternate between 500 and 600 Hz except for 2 minutes after the hour when
they transmit 440 Hz.

I usually set 2 Spectrogram markers - one at 500 Hz and one at 600 Hz - then
tune WWV for the 'best' voice signal and wait while watching the Spectrogram
screen - the demodulated tones will appear on the screen and will alternate
between the markers.  Touch up the tuning with the VFO knob to move the
displayed tones in line with the markers - takes a few minutes of 'watching
the pot', but you can observe within 1 Hz easily.

For more information about the format of the WWV/WWVH broadcasts, go to
http://www.boulder.nist.gov/timefreq/stations/iform.html

73,
Don W3FPR

----- Original Message ----- 

| I think I was at most 20-30Hz off calibration, but I decided to try this
| method. Concept is pretty straight forward. My problem is with zeroing
WWV.
| I don't recieve it very well here. What I did was to switch between LSB
and
| USB and match the tones. There was some other noise on LSB that made it
| difficult for me to decide when they matched, so I tried running the
signal
| through Spectrogram. I had to change filter to FL2, because the noise on
LSB
| caused the reading to be erratic. After changing to FL2 I brought the two
| tones to 328Hz on both sidebands by matching VCO and BFO via c22. They
| matched with displayed frequency at 9999.74.
|
| This seemed logical to me, but I am not ready to bet I got this right.
Since
| WWV is so bad here I am not sure if I really made more accurate. Bands
were
| pretty dead after I did this, but I am tuning New York Radio (weather) at
| 10051.50. ????? Hope that's where it is supposed to be :)
|
| If I got something wrong here I'd like to know. I am trying to relearn
| electronics and radio theory with my K2. If this is right (or wrong for
that
| matter) it was easy follow and easy to do.
|
| John n1sjz
| K2 #3596
|
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