K2 4 MHz reference oscillator calibration

[Ben Hofmann K1NT]

I need to calibrate the reference oscillator in my K2.
 Don't have any test equipment so I'll need to do it
against WWV at 10 MHZ using the N6KR method.

I'm a little confused as to how to zero beat the WWV
carrier as it instructs me to.  The instructions say
to zero beat the carrier precisely, or adjust the VFO
for best quality on a voice signal.  So, assuming
these are both happening at the same time (if they're
going to produce the same result) if I have the voice
tuned correctly (using USB or LSB mode), I can't hear
the carrier, so how can I zero beat it?  What am I
trying to zero beat the carrier against anyway?  Also
isn't the voice reception dependent on the BFO setting
of the filter?  My filter settings are not yet
optimized, I was planning on doing that after doing
the reference oscillator.  I'm confused about all
these points.

I've also read AB9GV's notes on W3FPR's web page, and
I think they just confused me even more.

Can anyone shed some light on this for me to make it a
little more clear?

Thanks.

-Ben  KB1AHR
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[Don Wilhelm-3]

Ben,

I believe you may be misinterpreting what is meant by 'zero-beat'.  What it
really means is to place the transmit frequency at the same place as the
signal that you are receiving.  More details on just how to accomplish that
in a transceiver when you are moving both the transmit and receive
frequencies if you ask about that specifically (you move the receiver to
accomplish that feat) - but now on to how to properly tune WWV --

You can get close by listening to the voice announcements, but that is only
roughly close but for adjusting the reference, you want to be REALLY close.

WWV's transmitting format says that they transmit 500 Hz and 600 Hz tones on
alternate minutes - and that is the fact that I use.  I crank up Spectrogram
on the computer and set one Spectrogram marker to 500 Hz and another to 600
Hz - of course, I have the K2 audio output connected to the soundcard input
and the sound comes out of the computer speakers - and I wait a while
looking for the tones to line up with the Spectrogram markers.

If you are in a place where you can receive both WWV and WWVH, you are
fortunate because you will see both tones, when WWV transmits 500 Hz, WWVH
transmits 600 Hz, etc.

If you happen along during one of the quiet minutes, you will just have to
wait, but you can get a good indication af where you are from the 1000 Hz
tone that is transmitted for one second at the start of each minute.

Folks with perfect pitch will be able to tune it correctly almost instantly
without the aid of Spectrogram, but those of us who lack that gift must
resort to non-auditory aids such as Spectrogram.

Once you are receiving the WWV 500 and 600 Hz tones at those audio
frequencies, you are at the 'zero beat' frequency. and you can then follow
the N6KR method easily.

If that was not adequately clear, sned me a note off-reflector and we can
straighten it out.

73,
Don W3FPR

> -----Original Message-----
>
> I need to calibrate the reference oscillator in my K2.
>  Don't have any test equipment so I'll need to do it
> against WWV at 10 MHZ using the N6KR method.
>
> I'm a little confused as to how to zero beat the WWV
> carrier as it instructs me to.  The instructions say
> to zero beat the carrier precisely, or adjust the VFO
> for best quality on a voice signal.  So, assuming
> these are both happening at the same time (if they're
> going to produce the same result) if I have the voice
> tuned correctly (using USB or LSB mode), I can't hear
> the carrier, so how can I zero beat it?  What am I
> trying to zero beat the carrier against anyway?  Also
> isn't the voice reception dependent on the BFO setting
> of the filter?  My filter settings are not yet
> optimized, I was planning on doing that after doing
> the reference oscillator.  I'm confused about all
> these points.
>
> I've also read AB9GV's notes on W3FPR's web page, and
> I think they just confused me even more.
>
> Can anyone shed some light on this for me to make it a
> little more clear?
>
>

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