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Old February 3rd 07, 05:18 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Best Books/Websites for Antenna Theory and Building Recommendations

Jimmie D wrote:
One such mistake is calling a 4 ft long antenna that
has a coil to make it resonate on the 10M band a "10M
loaded 1/4 wavelength antenna".


They should be more careful and specify that they are
talking about electrical lengths, not physical lengths.

For instance, the following stub is electrically 90
degrees long even though it is physically only 38
degrees long.

1/4WL stub
-------------------+--------
27 deg, Z0=500 11 deg, Z0=50

Incidentally, this is how a loaded antenna can be
90 degrees long electrically while being physically
much shorter than 90 degrees.
--
73, Cecil http://www.w5dxp.com