You can learn a whole lot about dipoles reading the ARRL Antenna Book. Yes,
thicker wire will give better wider coverage, but the 3 to 1 VSWR bandwidth
will never cover the whole band.
What I would do is decide the portion of the band that will be used most
often and set resonance centered there. For the times you want to venture
to another portion, use an impedance matching network (antenna tuner).
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] 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
Towertalkians....
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
difference.)
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?
Lee Buller
Liberal Arts Major
K0WA
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.
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_______________________________________________
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.
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