I'm just getting setteled into a new QTH and funds
are tight so instead of buying a tuner to tune my Van
Gorden "All Bander", I decided to see if I could
trim it to resonance on 40m.

For those who don't know, the All Bander is a
ladder line fed 134' dipole. It comes with 100'
of ladder line but I didn't need nearly that much so
I trimmed the ladder line to 50'. At that point I
have a 12 turn, 5-1/4" dia coax choke then 20'
of RG58 going to my SWR meter.

As a 134' dipole, the antenna presented a good
swr at 5, 20 & 28 mhz. I wanted 40m so I started
trimming. By the time I was done I had shortened
the antenna by about 25 feet per side. I'm not sure
exactly how much (+/- 1 ft) I trimmed but I was
VERY carefull to keep the antenna even sided.

The antenna now presents a good SWR centered
at 7.151 mhz but it also is OK at 18-19.5 and
26.5-28.5! Sweet! Performance seems good, too
(or maybe condx are good now)...

The antenna is setup as a dipole with apex & ends
at about 17' AGL. It runs facing 290 & 110 degrees.
One end ends up in a tree, the apex up on my roof
and the other end via nylon twine to a telephone pole.

What I don't get is if I shortened it, why did the 20
mhz low swr point move *down* 1 mhz while the
5 mhz point went up to 7.151 and the 28 mhz point
went down 1/2 mhz?

I'm happy with the results as I now (with a seperate
dipole for 20m) have my 4 favorite bands: 40, 20,
17 & 10.

Anyone care to offer a theory as to what's going on
with this setup?

73's de Ken KG0WX