> So, then, what about this trade-space (again, in the world of fairly
> inconspicuous antennas)..
>
> You could have a ground mounted vertical (of whatever length)
>
> OR
>
> a shorter vertical sticking up from the roofline, with a bunch of wire
> as a counterpoise/ground screen on the roof. (or a vertical dipole)
In my opinion, the "optimum" solution consists of two antennas. The
first would be a roof mounted 22 foot vertical (either a "half size"
43' vertical with tuner or an R5/AV-620) for 20-10 meters and a ground
mounted 88' vertical (or inverted L - up 55 out 32) for 160-30 meters.
In this case "optimum" is defined as a minimum effort/impact solution
that provides reasonable performance on all bands.
73,
... Joe, W4TV
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of jimlux
> Sent: Monday, June 01, 2009 9:27 AM
> To: jim Jarvis
> Cc: towertalk@contesting.com
> Subject: Re: [TowerTalk] optimum vertical length
>
>
> jim Jarvis wrote:
> > Jim,
> ".
> >
> > Regardless of the electrical length of the antenna, though, getting
> > it up high and in the clear
> > is the important factor. A 40m vertical dipole plays
> amazingly well
> > on multiple bands, with
> > a tuner, if you can get the high current portion of the antenna up
> > 50' or so, in a tree.
> >
>
>
>
> So, then, what about this trade-space (again, in the world of fairly
> inconspicuous antennas)..
>
> You could have a ground mounted vertical (of whatever length)
>
> OR
>
> a shorter vertical sticking up from the roofline, with a
> bunch of wire
> as a counterpoise/ground screen on the roof. (or a vertical dipole)
>
> If one uses the old CB antenna rules of 12-15 ft max height above
> structure as a constraint, are you better off with some sort of short
> vertical dipole, up 30 ft on the roof, or with a 45 ft
> vertical, on the
> ground?
>
>
> Assuming you're not at the beach, etc. It seems that getting the
> feedpoint up in the air will reduce near field losses from
> the soil, at
> the expense of incurring losses in your groundplane/lower half of the
> antenna.
>
> _______________________________________________
>
>
>
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