I had a Challenger in Colorado. The counterpoise (used to increase bandwidth on
40 metres) ius supposed to be about 57 feet in length.
This antenna worked very well for me on the bands it wasn't supposed to work on.
I worked many nearby states on 160, and was satisfied with the results on the
other
bands too. The internal antenna tuner on the TS940 handled the VSWR by itself
except on (I think) 12 metres [which wasn't a main band for me anywuz]. There I
had to use the MFJ 989 to get the VSWR to the point where the TS940 internal
tuner could finish the job (and I recall having to "override" it.
I had the antenna guyed with some nylon rope about a foot or two above the
"gap."
The purpose of the guys was not to provide rigidity (hence the use of nylon,
which
stretches) so much as to insure that should anything untoward occur, the antenna
would stay in my yard. Although the Denver, Colo (as opposed to Denver, NY and
Denver, Pa) area can have some hefty winds, I never had any problems in that
regard. When I moved to Nevada, however, the story was not the same. For a
number of reasons, the antenna was left unguyed and eventually developed a
30-degree "list" about a foot above where it went into the ground. Another ham
had
his Challenger do the same thing but the angle was 90-degrees! So this antenna
MUST be guyed. The Titan survived Nevada's breezes (80MPH gusts) without
guying. I will admit to having an occasional SWR spike and gradual change. The
latter of which was probably due to the tuning rods getting out of alignment.
To the
best of my knowledge, I had no problems with wind noise in the receiver.
73,
Bob AA0CY
PS Interesting that no one seems to be praising or damning the MFJ antennas.
They look rather unwieldy in the ads. Maybe I'll get their in-the-house whip and
antenna tuner model and be entirely covert in my operations!
----------
From: Thomas R. Williams[SMTP:n2cu@buffnet.net]
Sent: Friday, June 12, 1998 10:27 AM
To: towertalk@contesting.com
Subject: [TowerTalk] Re: Vertical?
Steve,
I've been using a GAP Challenger since September until I get my beam and
wires up. I like it so much I'm going to keep it for use on 80m and 40m,
and as a search antenna for the other bands. This antenna works great on
40m and 20m; OK on the other bands. In fact, I almost decided not to put
up the beam, with all the expense associated with it. The only problem I
encountered was that the three 25' counterpoise wires needed to be
trimmed to 19' to resonate on 40m (where they have the only effect).
Mine is guyed with their kit at about the 20' level. I have taken the
antenna down once to change the resonating cap for 80m and had no
problem with the self-tapping screws - just don't over tighten. No first
hand experience with other makes but a friend who owns an R7 added guys
to his because the design has a propensity to snap off at the base
insulator in high winds. Operationally, he is very pleased with it.
73,
Tom N2CU
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