[Elecraft] RE: K1 band Suggestions

[Morrow, Michael A.]

Tim wrote:

> I'm not sure I need a K1-2 or K1-4.

Tim,

I have an early K1, ordered when only two-band boards were available, =
for which I built a 40/20 meter board and a 30/15 meter board.  But as =
soon as I heard that a four-band board was available a year later, I =
ordered one and built it for 40/30/20/15 meters.  In my opinion, the =
four-band board much *more* than doubled the utility of my K1 with =
separate two-band boards.  I can think of absolutely NO good reason one =
should choose a two-band version when the four-band version is =
available, for reasons listed below:

1.  It's cost effective.  For $60 more than a two-band K1, you get four =
bands for which you don't have to swap boards to cover. =20

2.  Swapping between two two-band boards is rather inconvenient, =
especially with the KAT1 installed, I can tell you from experience.  If =
you plan to use the internal battery option KBT1, it's even more trying =
to swap boards because it's hard to grip the forward edge of the =
installed filter board to pry it out.

3.  Many builders report getting slightly higher maximum power output =
compared to the two-band boards.  I certainly did on 15 meters.

4.  In my opinion, the four-band board is actually easier to align.  =
Trimmer capacitors are used, rather than slug-tuned coils.

5.  It certainly requires much less build time to complete and align the =
four-band board, compared to two two-band boards.

I have found only one slight disadvantage to the four-band board that =
the two-band board did not have.  The tuning (alignment) is much =
sharper.  Because of this, I could not align the 40 meter section for =
nearly flat power output across the 7.000 to 7.170 MHz range of my K1 =
(I'm a fan of the 170 kHz VFO span option, at least in the USA, to cover =
all the 40 meter and most of the 15 meter CW band).  If I aligned it for =
the full seven watts out at, say 7.060 MHz, I could only get about one =
watt out at 7.148 MHz.  The simple solution to that was to increase the =
size of the 40/30 meter filter board interstage coupling caps CK and C10 =
from 2.7 pF to 4.7 pF.

I do like 17 meters, but even with the solar cycle dropping, I'd never =
give up 15 meter capability in exchange for a WARC band like 17 meters.

I re-built my old white elephant 40/20 meter board for 80/17 meters, so =
now my K1 can cover all six "official" K1 bands.

> I was thinking that 20 and 40 meters would probably be
> my choice of bands with a K1-2.

That would be obviously the best choice for a two-band version.  =
Informal polls on this list in the past show those to be the two =
favorite choices by far.

> I want to use the radio for portable use.

I can't think of a better choice in a multi-band QRP rig.  Consider =
making it a four-band model.

73,
Mike / KK5F