"DrDeath" wrote in message
...
"Jay in the Mojave" wrote in message
...
Hello DrDeath:

Why do you want a Balun, and on what type installation are you going to
use it????

Jay in the Mojave


DrDeath wrote:
I am trying to build a balun. I chose the one on this web site as I
like
the design
http://www.hamuniverse.com/balun.html
It states that, and I quote
"The number of turns is not critical because the inductance depends
more
on the length of the wire (coax) than on the number of turns, which
will
vary depending on the diameter of the plastic pipe that is used."
But it does not give the formula. It just says 18 to 21 feet.
I plan to use 4 inch pvc and I want to cover as much of the upper 11
meters as I can. Am I better off at 18 or 21 feet?

I'm just messing around with a home made dipole. I want the balun to cut
down on the TVI.



Just form 4 turns or so of coax in a coil perhaps a foot or so in diameter.
This will form a choke which will kill the current backfeed down the outer
side of the coax. You can actually build an endfed dipole out of coax.
Feed the hot (center) wire into about 9 feet of wire and form a loop (4 or 5
turns of coax) about 9 feet away from the feed. The outer conductor
(shield) of the coax will form the other half of the dipole with the coil
(choke) stopping the rf at that point. Simply move the coil (by turning
towards or away from the center feed) to adjust your SWR. No rf on the
outside of the coax. Presto

Questions, e-mail me at and I'll see if I can take a
digital photo for you. finger crossed - old digital camera which sometimes
has problems with close-ups LOL



73 from Rochester, NY
Jim