K1 - tuning range - Correction

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K1 - tuning range - Correction

Mike Morrow-3
Don wrote:

> It will not be necessary to change the CAL OPF menu settings unless a
> crystal is changed on the 4 band board.  

Of course you're correct, Don.  Thanks.  It just shows what I forget in the
years since I calibrated my KFL1-4.  Still, it may be appropriate to check
and perform the CAL OPF process.  It may have been done haphazardly, or it
may have been calibrated for some convention that the new user wishes to
change.  For example, I'll bet that there are K1s that have been calibrated
to, say, display 7000.0 kHz when *zero-beat* with a 7000.0 kHz signal, even
though that's not the way the K1 manual says to do the CAL OPF procedure.
Such a K1 will display 7000.0 but transmit on 6999.4 kHz, if RF-C13 has been
adjusted for 600 Hz CW offset.  I want the display to show transmit frequency,
so I calibrate the display with CAL OPF to show 6999.4 kHz when zero-beat with
a 7000.0 kHz signal.

> The calibration that is necessary with a change of a capacitor in the
> VFO is the VFO calibration which is achieved by changing the turns
> spacing on L1.

That's what I should have emphasized.  As you indicate it's not related to
the CAL OPF procedure at all.  As an aside for this adjustment, my KFL1-4
40m heterodyne oscillator crystal deviates from "nominal" (15000.0 kHz) by
+3.6 kHz, while the other three band crystals deviate from their nominal
frequencies by about -2.5 kHz.  Setting the start of the 40m band at about
6999.0 kHz (by adjusting turn spread on RF-L1) ensures that the other three
bands will reach all the way to the bottom of their CW portion.

Mike / KK5F
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