We loaded a pencil sharpener and a metal window frame while in college
and made contacts with both. I think both were on 15 but I forget for
sure.
###
BRETT WINCHESTER
[log in to unmask]
208-639-8386
###
-----Original Message-----
From: For blind ham radio operators
[mailto:[log in to unmask]] On Behalf Of Colin McDonald
Sent: Friday, August 24, 2007 10:06 AM
To: [log in to unmask]
Subject: Re: dipole antenna verses vertical and use of a tuner
less then 2 to 1 on all bands is a good thing.
A decent tuner will do that with any chunk of wire really.
You could put a 25 foot chunk of wire around your ham shack floor in an
underground bunker, and with an external tuner get less then 2 to 1 on
any
band....
The issue is that the antenna will not be efficient, and will not be
radiating properly except on the band it was specifically designed for.
You can tune the heck out of a 20 meter dipole and get an swr of less
then 2 to 1 on 160 meters, but it isn't going to work. A tuner fools
the radio into thinking that it has a 50 ohm load on it, and also fools
the swr meter into thinking the same thing. It doesn't suddenly make
your antenna efficient or allow it to radiate well on the band it isn't
cut for.
A standard understanding with antennas is that you can use an antenna on
the frequency it is cut for, and tune it for frequencies with shorter
wave lengths and it will still be relatively efficient on those other
bands. But it doesn't work for frequencies with longer wave lengths.
Most guys who use a dipole and say they can use it on any band, are
using fairly long dipoles, usually around a half wave on 75meters, or
longer.
That way, they are always tuning for frequencies that have a shorter
wave length then the antenna is designed for.
hope this isn't too confusing.
Basically, your 20 meter dipole shouldn't need any tuning via a tuner on
20 meters, and should work fine with the use of a tuner on 17, 15, 12
and 10.
Remember also, that a dipole doesn't start becoming efficient until it
is at least a half wave above ground.
For 20 meters this is a bit over 30 feet.
73
Colin, V A6BKX
----- Original Message -----
From: "Gery Gaubert" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, August 24, 2007 9:38 AM
Subject: dipole antenna verses vertical and use of a tuner
> Ok, not sure who wrote it but they said a dipole shouldn't limit you
to =
> just 1 band. This brings up a situation that happened to me the other
=
> night. I have a tuner and the dipole. I got everthing set up and
then =
> used th ldg z100 tuner. I then got less than 2.0 on all bands. Could
=
> tis be true or could something be wrong with my meter or tuner?
>
>
> --
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4:04 PM
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