[Elecraft] K1 VFO Range

[Mike Morrow]

Emil / KD1F wrote:

> I was curious as to the general consenses ... with K1 owners, on setting
> VFO Ranges.

Hi Emil,

I built K1 S/N 175 for 150 kHz VFO span.  I actually get about 170 kHz span.

The reasons I choose the wide option are listed below in order of importance
to me:

(1)  There's still quite a lot of CW activity to be found in the 7100 to
7150 kHz band.
(2)  There's every once in a while a 15m band opening, and the wide VFO span
allows tuning for propagation beacons, and tuning for CW activity in the old
Novice CW portion of the band.
(3)  The 30m coverage for the wide VFO span starts at about 10000 kHz, while
that of the narrow span starts at 10100 kHz.  Thus *only* the wide option
allows coverage of 10000 kHz WWV for time and STI info.
(4)  I'm able to cover about the first 20 kHz of the 40m phone band.  Since
the K1 receiver operates in LSB mode, a cross-mode contact is possible
there.
(5)  It is possible to copy, even with the low audio caused the narrow CW
bandpass filter, 40m shortwave broadcast stations.

I have found there to be no problem at all with the faster tuning rate of
the wide option, especially since R19 was added to later K1s at the VFO pot
to linearize the tuning rate at about 17 kHz per turn across the entire
tuning range.

I dislike the extremely light resistance to motion of the K1 VFO pot.  I
added a couple of layers of home-cut felt washers between the back of the
VFO knob and the panel.  That really helps to keep the knob from moving when
I let go of it.  I used thin felt cloth and added/removed layers until I got
a feel that was just right.  I would think that such would be helpful, even
had I used the 80 kHz option.

Were I not in an ITU region where I can operate above 7100 kHz, I guess I'd
be tempted to choose the narrow span.  But here there are, IMHO, many more
reasons to choose the wide option than to choose the narrow.

It's easy to change to the narrow option if you find that you don't like the
wide.

73,
Mike / KK5F