Towertalk
[Top] [All Lists]

Re: [TowerTalk] 80 4-square inside a 160 4-square? Pros and Cons please!

To: "Robert Shohet" <kq2m@earthlink.net>
Subject: Re: [TowerTalk] 80 4-square inside a 160 4-square? Pros and Cons please!
From: "Rick Karlquist" <richard@karlquist.com>
Reply-to: richard@karlquist.com
Date: Thu, 10 Jun 2004 18:04:22 -0700 (PDT)
List-post: <mailto:towertalk@contesting.com>
Robert Shohet said:
If I did this, then my existing 80 4 square
> (inv l's) would be inside the 160 4-square.
>
> I can't imagine this would be good for the 80 meter 4-square performance.
>
> Has anyone out there actually had an  80 4-square inside a 160 4-square
> and
> can tell me about actual changes in performance (that they have observed)
> of
> the 80 4-square and what they were?

I have 80 and 40 meter concentric 7-hex arrays.  The 80 meter
verticals have insulators at the midpoint with latching vacuum
relays across them.  I have to open up the relays on the 80 meter
verticals when on 40 meters and also float them from ground.
Failure to do this would result in severe pattern distortion on
40 meters.  The same general principle should apply to concentric
4 squares.

> Are these problems (if any) worsened by using BOTH antennas at the same
> time
> on different bands with two different radios?  Both 4-squares would be


Difficult.  You would have to use traps instead of relays.
The traps would act as loading coils on 80, so you would want
cancel the inductance with a series capacitance on 80.  This will reduce
bandwidth, which is one reason why I don't do it that way.

Rick N6RK


_______________________________________________

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

<Prev in Thread] Current Thread [Next in Thread>