Hi Art.
>From downunder my advice would be to go with the AV640 on a 20 foot foldover
support..
If you run the coax feed down the 20 foot support on insulated standoffs
and then put an omega style tuner at the base, the whole antenna will work
as a base fed vertical on 80mx as well. By omega, I mean two capacitors,
one series and one parallel to ground. The 20 foot support is grounded, by
the way.
In that way you will have a fairly good, albeit omni directional setup from
80mx through 6 mx (in fact you might even be able to get it going on 160mx
as well with a suitable loading coil!)
It doesn't have any gain compared with say a 3 element beam on the higher
bands, and will probably be noisier than dipoles, but given your time
constraint on the house moving and your access to a contest station for
serious HF Dxing, it still makes a good setup. By the way, the AV640 is
well capable of throwing 1500 watts at it on any band.
I use an AV640 on IOTA Dxpeditions and can only speak highly of its
capabilities. On my recommendation, a number of VK3 hams use this sort of
setup in areas where they are constrained from using towers because of
issues relating to renting, wives, neighbours etc. All are EXTREMELY
happy with their results.
Cheers
Peter VK3QI
----- Original Message -----
From: <atrampler@att.net>
To: <towertalk@contesting.com>
Sent: Sunday, October 21, 2007 12:24 PM
Subject: [TowerTalk] advice sought
> How long would you want to expect to be in a home to justify the expense
> of a tower install versus other antennas?
>
> I have a small backyard (70' x 100' roughly) with three trees in/around it
> that are no good for dipoles or other wire antennas, but enough room to
> squeeze a tower between them. I also have a Hy-Gain AV640 ready to go up
> for 30/40 meter coverage, and a roughly 20' tall, foldover support (4"
> OD/3.5" ID diameter pipe on lower section) to get that vertical up a bit,
> which allegedly helps the improvement.
>
> Due to health issues (someone else's) I have access to a free Glen Martin
> 50', 18" on a side tower/hazer and Mosley TA-53M. My xyl wants the
> guy-wires elevated, and I live on top of limestone. Short story: to put
> this up, I'm looking (with coax, new rotor cable, etc) at about $2500,
> another $1000 if I want to push it to 60' (which with the trees I might).
>
> Now my wife is talking about moving in two to five years...
>
> Would you guys put up a tower if you thought you'd be moving in that
> time-frame, or settle for a vertical? I may just sell the NIB AV640 and
> put up a Big Steppir vertical instead...I couldn't lay down 66' radials,
> or many that long, but I could have most longer than 35 feet, so 80 might
> be OK. From all I read, lay down 180 radials or so and I'd likely have a
> much better performer out of the Big Steppir vertical than the 3/8 wave
> Hy-Gain.
>
> I know this is slightly off-topic, but it is tower-related. WIth the
> small yard the guyed tower is not optimal, of course. The AN Wireless
> self-supporting towers look much more attractive and while needing more
> concrete, don't need the concrete for guy supports, more phillystran, etc.
>
> Advice is warmly welcomed and accepted. This is not going to be a contest
> station--ever--but a relaxing improvement over my mobile set up (where I
> worked 3B7C on 40, barefoot...). For contests I'm part of the stable at
> K5GO.
>
> FYI, the free tower belongs to my dad, N0JT. At 84 he has so much trouble
> getting up and down to and from the basement that he doesn't go on the
> air, and I am TRYING to convince him to let me move the rig/amp/rotor
> control into his bedroom. Wish me luck...I'd rather seem him have a few
> weeks, months or years of pleasure than just give it to me because of the
> stairs. But OTs can be stubborn, right?
>
> 73,
> Art, KC2G
> _______________________________________________
>
>
>
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