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Old September 22nd 05, 08:44 PM
Steve Nosko
 
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"Jerry Martes" wrote in message
news:b%NWe.1010$9a2.584@trnddc04...

"Richard Harrison" wrote in message
...
Cecil, W5DXP wrote:
"The 180 deg. phase reversing coil is the tricky part."

For UHF, you might prefer to use a 1/4-wave short-circuited stub in
place of a coil to reverse the phase. My 19th edition of the ARRL
Antenna Book shows such an antenna, "the super J-pole on page 16-25. At
other frequencies, this might be called a "Franklin Antenna". It`s a
1/2-wave in-phase with another 1/2-wave, one mounted directly over the
other. Best regards, Richard Harrison, KB5WZZI


Richard


Two half waves in phase, colinear. The 1/4 wave shorted "stub" is perhaps
the easiest way to get a 'good" 180 degree shift to get the segments in
phase. Used from early antenna design times...
73, Steve, K9DCI