[Elecraft] [K3}beat freq method

[Scott Ellington]

It seems there's a common misconception that one has to have some sense of musical pitch to use this method.  Especially with the K3, using CWT, it's completely unnecessary.  If you can hear the volume (not the pitch) of the tone going up and down, that's all you need.   Using an oscilloscope, you wouldn't have to hear at all.


Here is the procedure I recommend:

1.  Select fine VFO resolution (1 Hz).

2.  Select CW mode and set bandwidth to 500 Hz.  (You don't have to have a CW xtal filter.)

3.  If using WWV, do the calibration only when the carrier is unmodulated.  If you try it when there are audio tones, you may end up tuning to one of the sidebands.

4.  Using CWT, tune to the calibration signal.  This will get you very close to zero beat.

5.  Locate CONFIG:REF CAL.

6.  Tap SPOT to enable the sidetone, and adjust its level to be about the same as that of the signal.  You should hear the "beat", a fluctuation in volume.   If necessary, adjust the sidetone level for the strongest beat.  (If you can't hear it when adjusting the sidetone level, shift the VFO a few Hz.)  Tune the VFO for the slowest possible fluctuation, probably less than 1 per second.

7.  Note the VFO display frequency. If it isn't within 1 Hz of the calibration signal, adjust the REF CAL frequency in small increments, always retuning the VFO for zero beat as above, until the VFO display reads with 1 Hz of the calibration frequency. 

8.  Using the K3 utility, save the configuration.  (Or record the REF CAL value.)

9.  Cancel SPOT and exit the menu.


Note to Wayne and Eric:  Feel free to use this.



73,

Scott  K9MA


> 
> On 3/28/2011 1:31 PM, jrstorms wrote:
>> Trying to set the freq cal for the reference using method 2 since I do not
>> have a freq counter.  I may be tone deaf or something but I am not sure what
>> the beat-freq sounds like.  Wish someone would post or send a sound file
>> demonstrating the beat freq when off, close and good sounds like.  I tried
>> setting it on 15mhz and thought I was close but when listening to WWV on
>> 10mhz had to go down 300 hz to understand the voice transmission.  Also
>> 15mhz voice was "fuzzy" until I tuned off freq about 100hz.  Guess I am
>> confused at this point.  I do understand that this really just adjusts vfo's
>> so when at band edges I do not go out of band.  However when using DX spots
>> with N3FJP auto tune clicks I am off freq.  Have to dial around to get clear
>> signal so if I don't then they do not hear my calls well.  Am sending this
>> message to K3 support a well but appreciate any responses from the
>> community.
>> 

Scott Ellington
Madison, Wisconsin
USA