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
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