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5/4 Wave Two Meter Antenna

Recently I needed a good, simple VHF antenna that was easy to tune and provided a decent SWR.  My first choice was a J-Pole made with 300 ohm twin lead, but my initial tests proved such an antenna is neither easy to tune nor all that simple.  By a stroke of luck, I happened across this fine web page by N1HFX.  In his design, Mike used wooden dowels to support the antenna within the PVC.  In addition, he fed the antenna with a coaxial "pig tail".  I really did not want to do either of these, so I modified his design just a bit.

Electrically, my design is pretty much the same as the original, except I epoxied a chassis mounted SO-239 to the end of the PVC and fed the antenna from that point.  I also used a much thicker radiating element (#12 vs #18).  This lowered the resonant frequency a bit, forcing me to shorten the length to get it back into the center of the ham bands.

To tweak this antenna, you will need to adjust both the length of the main element (60-1/2"), as well as the matching section (15-1/8").  The former is not all that critical, and you can just fold over the end 1/2" at a time to adjust the length for testing purposes.  The matching section is another matter.  During tests, I found out the hard way that a 1/4" change could make the difference between a good or bad SWR.  Cut carefully if you attempt to optimize this antenna!