Kim W5TIT wrote:
"Mike Coslo" wrote in message

some snippage

I already presented some fairly comprehensive data on why it wouldn't.
That was pretty basic stuff.

That a quarter wave dipole antenna would work is fairly extraordinary.

Present your evidence and your theory/rationale.

- Mike KB3EIA -



Probably for the same reason loading up house plumbing will work, or loading
up a coat hanger, or whatever. With a tuner, and with other apparatuses in
use or not, coupling--whatever you want to call it--if a signal gets out, it
gets out and that is all that counts *sometimes.*

The idea of using a random length of wire or the rain gutter is a time
honored method of making an emergency/stealth or just plain experimental
antenna. Tuners often make these antennas work - some ok, some not so
well. And a large part of the not so good operation is when the tuner
can't match the antenna.

My MFJ949 tuner manual has several lengths that the user is encouraged
to avoid. According to them they are the worst possible line lengths:

160 meter dipole - 130 feet

80 meter dipole - 66 feet

40 meter dipole - 32 feet

If you do the calculations, you'll see what fractional wavelength those
antennas are for the respective bands.

note: if anyone looks up the MFJ info, they will see a few other
frequencies also on the "do not use" list. These are odd multiples of
1/4 wavelength, so I left them out of this discussion. But in general,
its a related problem - odd multiples of 1/4 wave are not so hot to use.

They note that if you have trouble tuning an antenna on a frequency you
want to use, you should shorten or lengthen the antenna by 1/8th
wavelength. Then you should be able to get the tuner to match things up.

- Mike KB3EIA -