On 1/22/2020 12:05 PM, donovanf@starpower.net wrote:
We're not discussing a choke operating at very high frequencies,
we discussing its performance at 1.8 or 3.5 MHz. At these frequencies,
a few feet of 50 ohm transmission line such as RG-142 or RG-400
connected to the end of a 75 ohm line has a tiny -- nearly immeasurable --
effect.
Great advice. AND -- exporting measurements of real antennas to SimSmith
(a very good freeware Smith Chart calculator and adding parallel wire
THHN or Teflon chokes to high dipoles for 40 and 80 shows that it often
improves the broadband match to the antennas!
My Choke Cookbook includes the physical lengths of each choke, allowing
about 8 inches for leads.
73, Jim K9YC
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