[TowerTalk] feedpoint capacitors

[Jim Brown]

On 4/25/2021 9:04 AM, John Keating wrote:
> Looking for advice on best type capacitors for legal limit L-C match at wire
> dipole feedpoint.

A resonant half-wave dipole presents a low-impedance load with 
relatively low SWR to 50 or 75 ohm coax, and should not require anything 
to match it to the feedline. Indeed, depending on its height and the 
conductivity of the earth under it, Z at resonance will be between about 
30 ohms and 90 ohms.

What IS often needed is some sort of matching in the shack for operation 
on bands like 80M and 10M whose bandwidth is a relatively high fraction 
of their wavelength. Tube power amps often have sufficient tuning range 
in their adjustable output networks, but solid state output stages 
require a tuner. As a contester, I need something much faster, and use 
stubs that I switch between for CW, RTTY, or SSB.

73, Jim K9YC