There is a huge amount written on the simple dipole antenna. I would first
consult any ARRL Handbook as well as the Antenna Book. One of my all time
favorite web sites is that of Dr. L. B. Cebik, W4RNL at
http://www.cebik.com/radio.html . You can spend absolutely hours reading and
absorbing all manner of antenna subjects.
During our Field Day operations, we have several 135 foot center-fed dipoles
up. They are fed with ladder-line (just the standard 'window' line, not the
'tuned-feeders' of y'or). We bring the ladder line to fairly near the shack
and attach a 4:1 balun. Then a short run of RG8X completes the run. With an
antenna tuner, you can match very well to frequencies of 75M and above. We
use them for 40 and 80M during FD. Works great !
At the frequencies we're talking about, it would seem to me to make little
difference whether you wrap or solder the dipole ends - I've done both with
no perceived difference. If you use the ladder-line technique above, you
don't have to worry about the diameter (and weight) of the dipole wire
Good Luck !
[mailto:firstname.lastname@example.org] On Behalf Of Lee Buller
Sent: Tuesday, August 30, 2005 1:54 PM
To: TowerTalk Reflector
Subject: [TowerTalk] Dipole questions for the Liberal Arts Major
As I am sitting here waiting for a huge programto load
into the file server I started asking myself about the
simple dipole...or Inverted-Vee (I know there is a
Although my dipoles seem to radiate, I am somewhat
dismayed at the "bandwidth" of a typical 40 or 80
meter dipole. Lets just talk 40 meters for now....
I was always instructed by an Elmer to cut the dipole
long and then use a tuner to tune the higher part of
the band. Others have instructed me to cut the dipole
for about 100 Khz up from the bottom and get as much
use as possible (not quite possible on 80 or 75
meters). Another Elmer cautioned me to make sure I
solder the ends of the dipole because the wire wrapped
at the end acts as a inductor with a capacitor in the
loop of the wire around the insulator which would make
the resonate point different than calculated. And yet
another told me to build a large wire diameter dipole
(out of RG58 or 59 or even RG8) to get some bandwidth.
So, with those comments that I have made...what do you
do when working with dipoles to get them to the point
where you get good bandwidth?
Liberal Arts Major
Common sense is in short supply - get some and use it.
If you can't find any common sense, ask for help from
somebody that has some common sense. - Lee Buller
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
TowerTalk mailing list
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
TowerTalk mailing list