On Mon, 17 Jan 2005 22:12:33 +0000 (UTC), Leigh Marrin/KM6JE
wrote:

Vinnie S. wrote:
Hi. If I want to talk abrefoot and run a dipole for 27 MHz in my attic, I
noticed there are numerous versions. The vertical is out for obvious reasons. So
there are inverted and horizontal. Is there any version I am better off using
barefoot?

Vinnie, I've had a lot of fun using various wire antennas on CB.
Horizontally polarized antennas don't do very well for local talkin' to
vertically polarized stations, especially on AM. AMers love strong "big
strapper" signals. However, a horizontal wire dipole will work fine in a
more effecient mode like SSB.

I understand you want a low profile antenna: you might try making a 1/4
wave groundplane on your roof. Buy a 102" whip and mounting bracket from
Radio Shack, hose-clamp the mounting bracket on a roof vent pipe, then
attach two or more slightly longer radials (maybe 106"), attach them to
the outside of the mounting bracket. Just lay the radials on the roof,
and perhaps thumbtack them when you've got the antenna tuned.

You can tune this 1/4 wave groundplane by trimming or lengthing the
radials: shortening a radial will cause the resonant frequency to go up.
Also, changing the angle of the radials will slightly affect SWR.

I've also used long wire antennas on CB: again, they usually end up being
horizontally polarized. For my current HF ham station (covering
10/15/20/40/80) meters, I use a 50' wire tied to a tree, a 8 foot ground
rod about 6 feet away from my radio, and a small/cheap MFJ tuner. Works
great for CW on those 5 bands, although on 20 meters I sometimes get some
RF "bites" when trying to tune on 20 meters/14mhz. On SSB, I usually can
get good signal reports on 40 meters, and SSB reception reports on other
bands are not quite so good, although the other operators can at least
usually hear me.

When I hook my Uniden PC-122 CB up to this long wire antenna, it works OK
for local SSB use, but on AM, I'm "mud-duckin'"..

A couple of times I've set up "stealth" ham and CB stations from motel
rooms when traveling. I'd ask for a second story room: at night I'd take
a roll of 24 gauge wire with a weighted end got up as much wire as I
could, and then for a ground for the tuner, I'd lay about 30 feet of wire
on the floor of my motel room. (When expecting maid service, I'd coil up
the inside wire.)

(Note that the above suggestion will cause much interference to
phones/TVs/etc.)

One last suggestion: I'd avoid antenna tuners from CB sources, as a
"Pyramid" brand tuner I had was terible. MFJ makes several tuners in the
$30 to $50 range that will tune both long wire and coaxial antennas.
While MFJ products typically have a very flimsy feel them, they are almost
always excellent designs that work well.

You might also want to check ARRL antennas books in the local library: I
had a lot of fun making and using a vertically-polarized and
vertically-mounted full-loop on CB. My loop used about 37 feet of wire,
with one end soldered to the coax shield and the other end soldered to the
coax center conducter.

In any event, HAVE FUN! If your antenna works, you can be proud of your
handiwork, as most of us CBers and Ham-bones are nuthin' but "appliance
operators".

73 and all them other good numbers to ya. --Leigh Marrin/KM6JE in Santa
Barbara, Calif.


Thanks. !

Vinnie S.