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Tom Donaly · September 16th 06, 10:14 PM posted to rec.radio.amateur.antenna

wrote:
On Sat, 16 Sep 2006 17:41:01 GMT, "Harold E. Johnson"
wrote:

The simplest fed is a L network with the C at the transmitter end
and the antenna at the unterminated inductor end. Works best
in the radiator is slightly capacitive looking.

Specificallly check the article "feeding the EDZ" as that
talks about the problem at hand.

Allison

Not really, the capacitor goes on the end of the coil closest to the higher
impedance. I'm certain his half wave will be appreciably above 50 Ohms.
Mine's about 2600 Ohms.

W4ZCB

You must have missed the second sentence where I state at
resonance It's a high resistance. I think we agree.

""For a "half wave" fed at the end the sign of the reactive part will
vary depending on it's real length. If it's really resonant there is
no reactive component only a very high resistive one. ""

However in a few cases I found the radiator and mountings to be
capacitive enough to result in no additional capacitance needed.
We agree but implementation sometimes takes other forms.

One of the sites posted suggests a PI network and again with the right
values it's the most flexiable and offers a low pass characteristic
that never hurts.

Allison

How do all these various matching schemes affect bandwidth?
73,
Tom Donaly, KA6RUH