Frequency offset with K144XV?

[Frank O'Donnell]

Today I installed a new K144XV 2-meter module and K144RFLK reference
lock board in my K3S.

While trying various experiments to put it through some paces, I set the
radio up with WSJT-X and configured it to listen for FT8 on 144.174 MHz,
after I manually added that frequency to WSJT-X's menu. I notice that
when I use the band pulldown on the WSJT-X top page to select 2m, it
briefly displays 144.174 000 as the frequency, but then quickly changes
to 144.173 998. The frequency on the K3S's display, however, still
appears as 144.174.000. I tried this a couple of times in a row, with
the same result. (Not an elbow-jog in this case.)

I assume this has to do with frequency offsets. Although the written
label on the K144XV case indicates that tests at Elecraft showed an
offset of +3.83 (Hz, I assume) for the 144 MHz subband and +1.95 (Hz)
for the 146 Mhz subband, based on the instructions for the K144RFLK
board I ignored those written values. Instead, I went to Config:XVn OFS,
hit 0 and noted that a REFLOCK value of -2.34 (Hz, I again assume)
appears on the K3S display. This, I gather, is derived from the radio's
master K3REF oscillator.

So, two questions. First, does it seem likely to others (as it does to
me) that the 2-Hz difference showing up in WSJT-X is caused by this
-2.34 (Hz) offset?

Second, is there a way to resolve this so that the frequencies shown in
WSJT-X and on the K3S agree?

Thanks and 73,

Frank K6FOD

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