[Milsurplus] More on the TCS

Mon, 8 Dec 2003 15:18:01 -0500

The antenna current indicator is only meaningful as a tuning aid to tune for
maximum. This maximum can only be related to actual power output only if the
antenna impedances are known. With a higher impedance antenna you'll see
less current (as long as you're able to match with the output controls) for
the same power output, than the current indicated when you're putting it
through a lower impedance antenna.
And the short antennas have low impedance,  so it makes sense that for the
purpose they were built, to work mainly into short whip antennas, the
matching circuit is designed to feed  low impedances.

You don't want to build a "balun" (balanced-to-unbalanced) but an "un-un"
(unbalanced-to-unbalanced) transformer, unless your antenna feedline is a
balanced line.

73, Meir WF2U

-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Ray Fantini
Sent: Monday, December 08, 2003 2:42 PM
To: [email protected]
Subject: [Milsurplus] More on the TCS

The low impedance output tank explains why my antenna current is so low,
do not see the advantage to building a low impedance tank when it would
be feed to relatively high impedance  " short" antennas, perhaps that's
where the huge inductance in the loading coil comes in. will build the 4
to 1 balm and see how that works, would be a lot more satisfying to see
the antenna current meter move. The gorse impedance miss match may
explain the harmonic problem on 160. Thanks for all the responses.
Have updated the pictures of the ham shack on my web page to show the
TCS station. At www.ka3ekh.net
Ray Fantini
Hope I have the spelling of impedance right and its not impendence.

_______________________________________________
Milsurplus mailing list
[email protected]
http://mailman.qth.net/mailman/listinfo/milsurplus