[Elecraft] Sync AM and checking VFO accuracy using WWV

[ab2tc]

Hi,

Boy, this thread is now incredibly long and I am not sure it if I want to
risk sticking my neck out with another entry. But I will.

There has been an intense debate for at least the past 8 years as to what
constitutes the "best" way to adjust the reference oscillator to the best
accuracy. Why not just stick with the "Zero beating" (Method 2) described in
the manual? All it requires is clear reception of WWV at the highest
frequency possible. No other instrumentation like a PC spectrum analyzer
program or frequency counter is needed. As for accuracy, the only possible
weakness I can see is the accuracy of the K3 audio side tone, but there is
no reason why this should not be accurate to a fraction of the Hz. Barring
that the method is perfect. (The expectation that the PC spectrum analyzer
is any more accurate is dubious). Aw, forget about Doppler shift in the WWV
signal. Under normal ionospheric conditions it's negligible.

AB2TC - Knut

PS. I would also describe the sound heard at near zero beat as
"whump-whump-whump" or "wow-wow-wow", but certainly not "chirp-chirp-chirp".
And I agree with the comments below.


k6dgw wrote
> There are a myriad of ways to do it if you're interested, however don't 
> underestimate the accuracy you can achieve with your ears and ability to 
> count when you get the levels equalized.  If you count 6 noise peaks in 
> 60 sec, you're within 0.1 Hz.
> 
> Something that hasn't been mentioned [and that I only alluded to in a 
> previous post] is doing this during the tone-free minutes on WWV.  The 
> tone modulation can make it very difficult, and in some cases your 
> result can be off by the frequency of the tone.
> 
> 73,
> 
> Fred K6DGW
> Sparks NV USA
> Washoe County DM09dn
> <snip>





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