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Old December 30th 03, 04:04 PM
David
 
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''Magnetic'' is appropriate, is it not?

On Tue, 30 Dec 2003 01:30:34 -0700, Eric F. Richards
wrote:

"Peter" wrote:

Hi there, is antenna matching important for receiving as much as for
transmitting. Sorry if this is a dumb question.


Well it's on topic and not about the latest conspiracy theory, so it's
not a dumb question.

The short answer is no.

The longer answer is that antenna matching with a transmitter is about
energy transfer -- a mismatched load will cause power to be reflected
back to the transmitter where it will be dissipated as heat in the
final amplifiers. This is not good, especially with solid-state gear.

For receivers, the same thing happens, but the energy lost is so
miniscule as to not be dangerous in any way. However, you will lose
energy from the antenna in a bad mismatch.

The best way to deal with this, from a receiving point of view, is to
get a good-enough match. You don't need an antenna "tuner" or complex
matching device; if you have, for example, an end-fed wire, a fixed
matching transformer such as those made by I.C.E. and other companies
(improperly often called "magnetic longwire baluns" which is a triple
misnomer), will set things up for you, gaining an s-unit and lowering
the background noise level. (The latter is a whole 'nuther
discussion.)

For more info on random, end-fed wires, see

http://www.anarc.org/naswa/badx/ante...e_antenna.html

If you're using a dipole, make it a multiband "fan" or "trapped"
dipole or a broadband folded dipole. Search for T2FD, TTFD or
"terminated, tilted folded dipole" for more info on the latter.

T2FD and other wire antenna info can be found he

http://www.hard-core-dx.com/nordicdx...ire/index.html

Hope this helps!


P