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

[Don Wilhelm]

Brendon,

A capacity hat can work on bringing the frequency downward, but how much 
depends on the size of the capacity hat and the inductance of the 
loading coil.

If you are not comfortable with modeling software, but have an antenna 
analyzer, you can still experiment.  Try a capacity hat and see how far 
it brings the resonant frequency down.  If it is not far enough, try a 
bigger hat.

The fact that you can lower the resonant frequency does not indicate 
efficiency (it only indicates the ability to properly load the transceiver).
Efficiency and lower SWR are not equal.  A 4 foot radiator is still a 4 
foot radiator and will have full efficiency at about 50 MHz. Using it 
with loading coil and/or top hat on lower frequencies will allow it to 
be used, but will not compare with a full size vertical radiator.

73,
Don W3FPR

On 3/24/2016 6:15 PM, Brendon Whateley wrote:
> Jim,
>
> Can you toss a capacitive hat on the top of the shorter vertical and see
> what difference that makes? I've not figured out how to use the modeling
> software yet!
>
>