[Elecraft] alternate method for finding zero beat with WWV

[Don Wilhelm]

Oliver,

That works great for those folks who have reasonable pitch 
discrimination.  My ears cannot discern the beat until the pitches get 
close enough to make a slow 'wow-wow' sound, but I do this on a frequent 
basis when aligning K2s (or setting the KX1's BFO and DDS parameters).
Sooo, I use Spectrogram as a crutch - just feed the K2's WWV audio into 
the compute soundcard (hear WWV on the computer speakers) and start up 
Spectrogram.  Knowing that WWV usually transmits tones of 500 and 600 Hz 
on alternate minutes, I put markers at 500 and 600 Hz in Spectrogram and 
tune first until the voice announcements sound intelligible, then tune 
slightly until the transmitted tones line up with the markers.  Use SSB 
mode for this, attempting to use CW will create confusion due to the 
dial offset equal to the sidetone pitch.

So, now you have 2 alternate methods of precisely tuning WWV.

73,
Don W3FPR

Oliver Johns wrote:
> Dear group,
>
> Wayne Burdick and others have given us methods for aligning the 4kHz 
> reference oscillator of the K2 using zero beat with WWV.  The only 
> problem is that it is sometimes hard to recognize zero beat.  Counting 
> the beats of the S meter works sometimes, but sometimes is fairly 
> ambiguous.  Here is a wrinkle on Wayne's method that I haven't seen 
> mentioned.
>
> WWV not only emits a standard carrier, but also emits standard audio 
> tones.  If you tune your K2 to WWV using, say LSB, you find that the 
> received pitch of the tone varies as you approach zero beat.  When the 
> K2's BFO is exactly zero beat with the WWV carrier, the received tone 
> should be exactly of the correct pitch.  But how to recognize that 
> correct pitch?  The answer is that the received audio pitch of the WWV 
> modulation is independent of exact tuning WHEN YOU RECEIVE IT ON AN AM 
> RECEIVER.  So, take any AM receiver capable of tuning WWV and listen 
> to the pitch of the WWV tone on it.  When the pitch from the K2 
> speaker matches the pitch from the AM receiver speaker, you have zero 
> beat.  You can even put the two radios close together and hear the 
> beats between the two pitches.
>
> 73,
>
> Oliver Johns
> W6ODJ
>
>  
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