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Old September 21st 04, 08:51 AM
Toni
 
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Hi Richard,

En Richard Harrison va escriure en Mon, 20 Sep 2004 10:24:54
-0500:

Toni wrote:
"This explains the "not exactly 50 ohms" thing."

The FET input resistance is high and a shunt diode probably has high
impedance at low signals.


Due to lower antenna loading, a high
receiver input impedance does better with a too-short antenna than does
a 50-ohm input. But high-impedance input may be more susceptible to
interference and overload.

Maximum power transfer to a receiver occurs when there is a conjugate
match between the antenna and its receiver. This may, however, not give
the best noise performance.


Yes, but my main objective for all this is feeding the receiver
with the signal comming from the antenna well above the roof, and
(try to) avoid feeding the noise picked by the feedline on it's
way down. Light dimmers, fluorescent tubes, the computer, TV,
etc. I can notice a noise difference when turning them on/off,
and that's what I want to solve/improve.

73s,

--
Toni

"Auto" = prefijo griego que significa "no funciona"