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Old May 12th 07, 10:39 AM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Phase Shift through a 75m Texas Bugcatcher Coil

Richard Harrison wrote:
Cecil
proposed a resistor matching the impedance at the tip of the antenna to
avoid a reflection. This also eliminates the troublesome ambiguity.


Actually a little more elementary than that. Take a base-loaded
75m mobile antenna and remove the stinger, leaving only the
coil. Install a resistor to ground from the top of the coil and
adjust the resistor value equal to the characteristic impedance
of the coil. This is the point where the feedpoint impedance
at the base of the coil is equal to the value of the resistor
in ohms. This is, of course, assuming the coil is less than
1/4WL long which it is for a typical mobile installation.
--
73, Cecil http://www.w5dxp.com