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Old January 6th 05, 05:54 AM
Eric F. Richards
 
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Howard wrote:

Huh? If I'm mistaken, which could be, at least give me a hint why I'm
wrong and I will follow up on it.


Oh, ignore our professional idiot.

You did miss something, however. The impedence mismatch makes the
energy transfer from the antenna to the receiver to be inefficient. 5
dB is just about right for any 9:1 matching transformer (from an
end-fed wire to a 50 ohm load).

I'm not going to attempt to explain the theory behind it since I will
certainly leave something out and the peanut gallery will come to life
again, but think about SWR and reflected power and how bad the
mismatch can be without the transformer vs. how bad it would be with
the transformer.

For a practiacal demonstration try (BRIEFLY) to feed a speaker from a
tube amp without using a matching transformer. (You'll want a
blocking capacitor, though.)

I know this isn't rocket science
as I work with rocket scientists and many know little about radio.


:-)

Until shown otherwise I stand by my statement that the balun will not
add gain to the antenna - though it has other characteristics that
will improve the received signal.


No, no *gain* added to the antenna, but better power transfer to the
radio from the antenna. 5 dB is what I've measured as well. I use
ICE prepackaged transformers and Mini-Circuits transformers.


Have a good one DX,
Howard
ps - I don't use a portable as my primary receiver 8-}


--
Eric F. Richards

"Nature abhors a vacuum tube." -- Myron Glass,
often attributed to J. R. Pierce, Bell Labs, c. 1940
 
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