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Old January 20th 04, 04:08 AM
Craig Buck
 
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You're making my head hurt but I think I am beginning to see the light.

--
Radio K4ia
Craig "Buck"
Fredericksburg, VA USA
FISTS 6702 cc 788 Diamond 64
"Bill Turner" wrote in message
...
On Sun, 18 Jan 2004 22:55:27 -0500, "Craig Buck" wrote:

I am baffled too., If the antenna is too short and therefore exhibits
capacitive reactance, why isn't the adding a coil (inductive reactance)
enough to balance it out? I guess I don't understand matching networks

at
all. If the antenna is too capacitive or to inductive add the opposite

to
get to zero. Seems like you add one or the other but not both to get a
match.


__________________________________________________ _______

You guys are making this way too complicated.

First, get an ARRL handbook and learn about L-matching networks
(entirely apart from antennas).

Then, picture your HF mobile antenna with no matching network, but tuned
to resonance. The feed point resistance will be typically 10-40 ohms or
so. Pure resistance, no reactance.

Now picture that same antenna with an L-network to raise the feedpoint
resistance to 50 ohms. Still pure resistance, no reactance.

Now, (here's the clever part) detune the antenna so it appears to have a
small amount of capacitance or inductance in series with it. This
becomes one of the two elements of the previous L-network. All you have
to do is add the other element of the L-network and connect the coax to
the junction of the other element and the base of the antenna.

Presto, it's matched! Make sense now?

--
Bill, W6WRT