Topband: INV L matching

[Richard (Rick) Karlquist]

On 5/14/2020 9:26 AM, Tom | SP5XO wrote:
>d,
> wideband match. Since short vertical inv L over reasonable ground should
> have roughly 20 OHm impedance that could work here as well.

The matching network that will maximize bandwidth
is an autotransformer wound on a 2.4 inch diameter
ferrite core.  For example, a transformer with a
3:2 turns ratio will transform 50 ohms to 22.2 ohms.
I use a homebrew autotransformer on my 90 foot
vertical which has around 25 ohms drive impedance.
See Jerry Sevick's book on RF transformers for
info on "un-uns".

Rick N6RK