[Elecraft] Zero-Beat Procedure for the Elecraft K3s (DRAFT)

[Don Wilhelm]

Clay and all,

That is good work, but I feel it is overly complex.

The secret to using the zero-beat method for the Reference Oscillator is 
in the ability to correctly tune WWV (or other standard station) to 
zero-beat.

I make use of an audio spectrum analyzer running with my PC and 
soundcard.  Spectrum Lab will do fine, but I use Spectrogram v16.  For 
those who want Spectrogram 16 or 5.17, they are available on my website 
www.w3fpr.com - scroll down near the bottom of the opening page and you 
will find the links.  Those files are local to my website and have been 
scrubbed many times for virus.

With Spectrogram running, first tune WWV and feed the K3 audio to the 
soundcard input using SSB mode.  Knowing that WWV transmits 500 and 600 
Hz tones with a 1 second 1kHz tone at the start of each minute, it is 
easy to properly tune WWV (in SSB mode).

Now switch the K3 to CW mode, and you should see the carrier displayed 
at your sidetone pitch on the Spectrogram screen.  Adjust the tuning 
slightly if not true.

Now that WWV (or other standard station) is tuned properly, lock the VFO 
and follow the other instructions in the Zero-Beat (Method 2) in the manual.

All done.

73,
Don W3FPR

On 6/4/2018 12:32 AM, Clay Autery wrote:
> It was not until recently that I acquired the TMP connectors and crimp 
> tool to make a proper jumper cable from my K3s' J1 connector on my K3s’ 
> TXCO (TMP) to my frequency counter (BNC), so I have always used the 
> "zero-beat" method.  Periodically, I go back and repeat the TXCO 
> calibration using a modified "Method 2 (Zero-Beating)" procedure (K3s 
> Owner's Manual, Rev A1, p.53).  It originated (and grew) from a post 
> snippet from this reflector. (Thanks Scott, K9MA)  IF you have an 
> Elecraft P3 Panadapter, or other, connected to the K3s’ IF Out, you can 
> use it to great facility in visualizing and verifying what "is" and what 
> you "do".  I have written this procedure with the assumption that the P3 
> is not present or is not being actively used beyond observation.  I may 
> write an addendum later to include the active use of the panadapter vs. 
> as an observational tool only.
> 
> For obvious reasons, the manual says to use the highest WWV frequency 
> available, and references 10, 15, and 20 MHz.  Just in case you missed 
> it, NIST put WWV at 25 MHz back on the air sometime in 2015, but they 
> switched it to circular polarization around July of 2017.  Link: 
> http://www.arrl.org/news/wwv-25-mhz-signal-swapped-to-circular-polarization 
> OR, back to the half-wave dipole depending on which reference you read. 
> <confused>  Point is, that I am having great luck using it as a 
> reference signal.
> 
> Of interest to some may be the inclusion of a very simple equation that 
> tells you how much and which way to adjust REF CAL in one shot.  No 
> fuss, no muss, no futzing around and back and forth. You make one 
> observation, one calculation, one input and you're done.  (Usually) MOST 
> of the procedure is in the setup.
> 
> Go here to grab a PDF of the DRAFT document of the procedure I use: 
> http://www.montac.com/pdfs/Elecraft_K3_Zero_Beat.pdf
> 
> 73,
>