Thanks for the notes, Jim - it is for 80m. Sorry I didn't include that
detail!
73,
-Brian n8wrl
Another concern should be physical separation from transmitting antennas.
1/2 wavelength at the lowest freq is the usual recommendation.
DX Engineering has a receive four-square system that works very well on 160
and 80 with side lengths of 98 feet. It uses active elements. Height
difference between the elements should not be more than about 10 feet at
that side length.
73 John
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
> Sent: Thursday, September 29, 2005 8:27 PM
> To: n8wrl@arrl.net; TowerTalk@contesting.com
> Subject: Re: [TowerTalk] 4-sqr & terrain
>
> At 04:48 PM 9/29/2005, Brian Smithson wrote:
> >Hello Group!
> >
> >I'm trying to pick the best spot to site a 4-square on my property.
> >I've got about 12 acres to play with but there are various
> obsticles -
> >two towers, a barn, pond, steep hills, etc. It slopes in
> various places
> >but the most-level spot may become an arena for horses. My
> question is,
> >how sensitive is the pattern to differences in height of the
> verticals?
> >That is, can the bases be ~3 feet difference in level from
> each other?
>
>
> first question.. is the 4 square for 80m (in which case 3
> feet is in the
> noise) or for 2m, (in which case it's not...
>
> if you're on 40m, a quarter wavelength is, what, about 33 ft,
> so you're talking 1/40th of a wavelength with 3 ft.. probably
> not an issue. Probably not even an issue with 20m (unless you
> have some sort of exotic phasing system that will be picky
> about tiny changes in mutual Z, and then, you have much
> bigger problems to worry about)
>
> I'd guess that the small scale slopes will have less effect
> than other things around (horses, towers, etc.).
>
> It's actually,
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers",
> "Wireless Weather Stations", and lot's more. Call Toll Free,
> 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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