[Elecraft] [KX3] Re: Strong recommendation: MFJ 18xx-series single-band whips for KX3, etc.

[Tom Crayner]

John,

Just like Bruce said regarding the 1899...

I started at one tap position for 20M and then changed the coil tap to
another for 40M. When I wrote my original note that was my 40M testing... I
failed to mention in my earlier email. In this case the whip length itself
isn't adjusted, just the tap, and I guess to be optimal the length of
counterpoise should be as well, but I cut corners and didn't do that.

I got lazy and after getting it close enough I switched on the ATU of the
KX3 and it tuned to 1.2:1. That ATU is a great feature for use with
antennas such as these where bandwidth is going to be narrow and tuning can
be a pain without a good ATU. Cannot imagine life without one when doing
portable stuff with compromised antennas... I'd spend all day tuning up...

Tom, W2YF


On Thu, Mar 24, 2016 at 10:21 AM, Bruce Nourish <w0mbt at w0mbt.net> wrote:

> Most of the electrical length of these physically-short whips is in the
> loading coal. Adjusting the length of the 40m whip as you describe would
> only move the resonance point around within the 40m band. To move the
> resonance point between bands, you'd need to tap the coil. MFJ makes such a
> whip; scroll to page 2 of this doc and read about the 1899T:
>
> http://www.mfjenterprises.com/support.php?productid=MFJ-1810T
>
> On Thu, Mar 24, 2016 at 6:55 AM John Pitz <crustacean at brig-elec.com>
> wrote:
>
> > Hello All,
> >
> > Please excuse the amateurishness of this question, but could you get one
> > of these whips for a low band such as 40M and use it on say 20M if you
> > don't extend it fully?
> >
> > John Pitz
> > KD8CIV
> >
> >
>
>