[Elecraft] RX/TX different?

[Kevin Cozens]

At 09:06 AM 01/07/2004 -0600, you wrote:
>When I tune in WWV using Spectrogram e.g., set markers for 500/600hz on 
>even/odd minutes (respectively) and/or use a 1Khz 'at the tone' marker my 
>RX displays 9999.99 Khz. I can live with that.
>
>Yet there have been a few SSB contacts that that I tell me they are 
>receiving me 'low'. i.e. if someone is (supposedly) on 18150.0 I have to 
>tune to 18150.22 for them to tell me I'm now xmitting on 18150.0

If you K2 is within 10 Hz on 30m you should not be off by 220 Hz two bands 
up even if C22 is not adjusted right. Its possible that some of the 
frequency error reported by the other station may be due in part to 
frequency inaccuracies on their end.

>Obviously, the resulting dial accuracy is dependent on just how precise 
>one can tune in WWV. I should be able to 'zero beat' precisely to WWV 
>using Spectrogram, right? i.e. after I dial in WWV using the markers per 
>above I can then adjust C22 using Waynes method (e.g. via CAL FCTR and 
>alternating between TP1 & TP1 until the two test points match, then run 
>CAL PLL)?

Yes, Wayne's technique is the best method to use to check/improve your dial 
calibration. Tune to 10MHz by zero beating WWV, using Spectogram, or 
measure your transmit frequency with an external frequency counter and 
adjust the VFO until you are as close to 10MHz as possible. I did the 
latter as I had a frequency counter available.

You don't match the values you read in CAL FCTR between TP1 and TP2. You 
adjust C22 until the difference in readings between the two test points is 
as close to 10Mhz (or the frequency you measured on the frequency counter) 
as you can get. You then run CALL PLL. After CAL PLL, you MUST run CAL FIL 
for the mode and filter you are using while you are adjusting C22. Adjust 
the setting up 1 and down 1. By doing this for only the one mode/filter for 
now, you save some time.

One important note to make life easier. You should adjust C22 only when you 
are measuring TP1 (the PLL). The PLL frequency is about 3 times the BFO so 
adjustments to C22 are more noticeable if you are reading the PLL frequency 
vs. the BFO. It will help you get a more accurate calibration.

Once you are done, run CAL FIL on ALL modes and filters. The first time I 
did this, I was dead on frequency on the low bands and off by no more than 
30Hz on the upper end of 10m.


Cheers!

Kevin.  (http://www.interlog.com/~kcozens/)

Owner of Elecraft K2 #2172        |"What are we going to do today, Borg?"
E-mail:kcozens at interlog dot com|"Same thing we always do, Pinkutus:
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