Re: [Elecraft] [K3] Display frequency accuracy on 6 meters

2009-02-25 Thread Julian, G4ILO



Bill W5WVO wrote:
> 
> I work 6-meter WSJT digital modes, where frequency differences measured in
> Hz are significant. Working with various other stations whose technical
> capabilities I trust more then my own, I've concluded that my K3 is about
> 96 Hz, plus or minus, on the low side of actual when the VFO is set to a
> kHz integer frequency on 6 meters. (E.g: display frequency 50260.000,
> actual frequency 50259.904.) I would like to tweak this in to a higher
> degree of accuracy. Since I didn't put together my own K3, I'm not at all
> sure how to do this. Can someone knowledgeable point me in the right
> direction? If test equipment is needed, let me know what it is.
> 

The reference oscillator calibration procedure is described on page 49 of
the manual. You don't need any special test equipment. You just need to be
able to receive a signal of known accuracy.

There are various ways to do this, and if you can receive WWV then you can
probably use that. What I did is tune a short wave broadcast station 1KHz
high or low in SSB mode and then adjust the reference oscillator so the
heterodyne was precisely 1KHz, using the sound card software Fldigi to
measure it. If you have a frequecy counter that measures audio frequencies
you could feed the audio from the K3 into that, I suppose.

Most short wave broadcasters are accurate enough on frequency for our
purposes, but it makes sense to tune in several and check the heterodyne is
the same pitch, to avoid picking one that is off-frequency.

-
Julian, G4ILO. K2 #392  K3 #222.
http://www.g4ilo.com/ G4ILO's Shack   http://www.g4ilo.com/blog.html G4ILO's
Bloghttp://www.g4ilo.com/kcomm.html KComm for Elecraft K2 and K3 
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[Elecraft] [K3] Display frequency accuracy on 6 meters

2009-02-25 Thread Bill W5WVO
I work 6-meter WSJT digital modes, where frequency differences measured in Hz 
are significant. Working with various other stations whose technical 
capabilities I trust more then my own, I've concluded that my K3 is about 96 
Hz, plus or minus, on the low side of actual when the VFO is set to a kHz 
integer frequency on 6 meters. (E.g: display frequency 50260.000, actual 
frequency 50259.904.) I would like to tweak this in to a higher degree of 
accuracy. Since I didn't put together my own K3, I'm not at all sure how to do 
this. Can someone knowledgeable point me in the right direction? If test 
equipment is needed, let me know what it is.

Bill W5WVO
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