EZNEC Example of Short Vertical w/ Matching Coil
"Owen Duffy" wrote in message
...
"Frank" wrote in
news:0hqZh.14503$JF6.1620@edtnps90:
...
In any case, whatever you do, it is unlikely that a single element
will achieve
a match. Unless you are very lucky you will need a two element
network. For example a shunt L, series C, or Series L, shunt L, or
series L, shunt C will achieve a match for virtually any capacitive
load. A Smith Chart is ideal for such analysis.
But one of those reactances can be supplied by detuning the loaded
antenna,
the second typically by a shunt coil.
For example, if the R component at the base at resonance is say 20 ohms
(radiation resistance, equivalent coil resistance and equivalent ground
resistance), detuning the radiator + loading for about 25 ohms of
capacitive
reactance will allow a shunt coil of about 2uH to form an L match at
3.6MHz.
Owen
True, I was forgetting the loading coil.
Frank
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