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Old January 19th 04, 03:38 PM
Dave Shrader
 
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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.

Just another dummy trying to figure it out.


Adding the proper reactance in SERIES in the antenna tunes it to
RESONANCE. But, the feedpoint, load resistance, will be low; example 10
+ j0 ohms, and the VSWR will be 5:1.

Keeping some reactance in the antenna allows a SHUNT REACTANCE to be
used for tuning. The input impedance then becomes the parallel
combination of the antenna impedance with the shunt impedance. If there
is Q in the circuit then an impedance transformation takes place based
on the value of [Q + 1].

DD, W1MCE