Very true Tom,
I am using on 20 meters a Telrex 20M546. The Telrex uses a T network. The T
bars
are very close to the driven element and longer than normal. They use no series
capacitors.
Or should I say condensers as they were called when Mike Arcelino designed the
Telrexs.
73 Price W0RI
The only noise caused by an element charging is a "pop" or arc as the element
moves closer to air potential, until the voltage is high enough to break down
some insulation path to earth. This is a huge problem with T network antenna
tuners that feed big antennas without a ground leak path. The antenna trickle
charges the output capacitor (with microamperes of current) until the cap
flashes over. This sudden rings the tank with high voltage, and that blows the
diodes in the directional coupler detector.
We certainly do not want things to charge to the point something flashes over
and is damaged, but a ground leak does not reduce p-static (corona) noise. A
ground leak does not reduce the chance of a lightning strike, either. Neither
do
those tower whiskers (NASA has extensively tested that).
73 Tom
_______________________________________________
Topband reflector - topband@contesting.com
_______________________________________________
Topband reflector - topband@contesting.com
|