Jack Painter wrote:
wrote
Can anyone tell me where I can find plans for building a great
jpole
that is dual band and has a low swr?

Also, do you have to ground or use a balun with a jpole? I have
seen
some plans that say you dont on their design.


I use the design found at : http://www.hamuniverse.com/jpole.html
Standard 1/2" copper pipe with acid-free solder, no balun, no choke,
and
approximately 70' of Belden 9913 feedline. Grounded roof top mast
uses #4
bare copper lightning down conductors in two directions, coax is
shield
grounded at ground level, then to an I.C.E lightning surge arrestor,
then to
a 25w marine vhf transceiver. The J-Pole is bench centered on 156.800
Mhz
and allows 18-23w output (at the transceiver) across the vhf-marine
band.
Very experienced antenna builders on this group have explained that
my
results without a balun/choke at the feedpoint is a combination of
luck
concerning feedline length and operating bandwidth. Accordingly, your
results would most likely vary, but the design is a confirmed
performer.

73,
Jack Painter
Virginia Beach, Virginia

How do you "adjust" this antenna for optimum swr? Would it change the
results using "qwick connect" fittings instead of welding/soldering?

Are the end caps that are soldered on included in calculating the
length?