Peter wrote:


Have you considered putting up a 50 ohm coax fed inverted V 80 metre
dipole and then adding a 40 metre dipole to the same coax feed point?
It can come down at a sharper angle than the 80m one or run at right
angles to it. You'll then have 80, 40 and 15 metres since the 40m
dipole will work has 3 half waves in phase on 15. You can hang
dipoles
for the other bands to the same feeder as well. Be prepared for some
cut 'n try of course! This system elimates the need for an ATU but
you'll find the usable bandwidth on 80m to be only just a couple of
dozen kHz or so.

Should be wider than that...I usually get 200-250-300 kc "2:1 SWR" on
80m,
using common fed dipoles. About the same as a single dipole...I just
checked
mine out of curiosity, and I'm tuned at about 3910kc. Using the SWR
meter
in the rig, I hit 2:1 at about 3.810. Actually, I usually tune about
3850 or
so, but it seems to have changed a bit, probably cuz a large tree was
cut down,
and I had to change the antenna layout a bit. But anyway, I'm getting
3.810
to 4.000 usable with no tuner if you consider 2:1 the limit. I am using
an
MFJ 989c tuner, but usually only for the wattmeter...But I can use it
to go
off the beaten path.. Right now, I've got 160,80,40 on one coax feed. I
can
use the tuner for any of the other bands. Even with the coax loss, it
usually
works ok about anywhere. Works real well on 30m, even though the SWR is
about
5:1 or so..At that freq, and the rg-213 I use, 5:1 doesn't add too
awful much
loss. I get real good reports. Running the different dipoles at right
angles
is the best, with almost zero interaction. As they start to parallel,
the
coupling between them will increase, but is usually no big deal.

It's best to always start, and tune the lowest band first, and then add
and
tune each higher band dipole as you go along. Thats the fastest and
easiest
way. If you have coupling problems, it will almost always show up on
the
higher band dipole. Almost never on the lower. IE: An 80 and 40 dipole
on
the same feed, would usually show any coupling/tuning problems on 40m.
Often,
just moving one of the 40 legs a few feet farther away will let it tune
fairly
normally. Once set up, and tuned, the performance of the paralleled
dipoles
will usually outdo most tuner driven/ladder line fed single dipoles. No
tuner losses, no knob fiddling, and you have a normal dipole pattern on
each
of the bands used. It's been my preferred setup for years as far as my
"everyday" lower band antennas. The efficiency is in the 95%+- range
depending
on the band..."I use 213 coax" Can't really improve on that much..Even
lowly
rg-58 will be pretty low loss on the lower bands, as long as the length
is
not excessive. MK