[Elecraft] Transverter calibration

[Mike Harris]

 From the K144XV Reference Oscillator Phase Lock Option Installation Manual:

Recalibrating the K144XV

With the K144 XV Reference Oscillator Phase Lock option installed, you 
no longer need to calibrate the two crystal local oscillators as 
described under Frequency Calibration in the K144 XV Installation and
Operation manual. Once the proper settings are made in the CONFIG menu, 
the calibration occurs automatically as both oscillators are phase 
locked to the master K3REF oscillator in the K3.

Enable the calibration as follows:

Be sure you have K3 Firmware ver. 4.42 or later installed.

Tune the K3 to any frequency in the 2-meter band.
Hold CONFIG to access the CONFIG menu and select XVn OFS, where n is the 
transverter number you assigned to the K144XV (see Enabling the K144XV 
Module in the K144XV Installation and Operation manual).

Tap the 0 switch until you see REFLOCK on the K3’s LCD. The 
automatically calculated offset will appear in upper half of the K3’s 
LCD. This enables reflock for both the 144 and 146 MHz band segments.

You don’t have to repeat the procedure for each segment.

If the K3 EXREF option is also installed, the K3’s reference oscillator 
itself will be automatically calibrated by the external 10 MHz 
reference. In this case, enabling REFLOCK for the K144XV module will 
allow the K144XV frequency to track the external reference. The accuracy 
of the 2-meter frequency will be less than that on HF by a factor of 
about two, due to the higher frequency of the K144XV local oscillators.

I have that installed in my K3 along with the EXTREF module driven by a 
10MHz GPSDO. From a cold start the automatically calculated offset can 
be seen to change +100Hz as the TCXO drifts with warm up.

Belief and reality ain't necessarily the same thing.

Regards,

Mike VP8NO

On 22/06/2018 15:46, Don Wilhelm wrote:
> Alan,
> 
> I have not worked with the REFLOCK, but I believe the XV1 OFS parameter 
> must still be set in the menu.  The REFLOCK cannot read the labels on 
> the top of the K144XV.
> 
> 73,
> Don W3FPR