Towertalk
[Top] [All Lists]

[TowerTalk] Is it worth it to move 2El Quad from 50ft to 100ft?????

To: <towertalk@contesting.com>
Subject: [TowerTalk] Is it worth it to move 2El Quad from 50ft to 100ft?????
From: n4kg@juno.com (n4kg@juno.com)
Date: Wed, 17 Oct 2001 12:34:11 -0600
John,

Your C31XR at 110 ft is very close to 3 WL high (105 ft).
A 3WL high antenna on 10M has a first lobe centered
at 5 degrees (3db points 3 and 8 degrees) and a second
lobe centered at 14.5 degrees (3 dB points 11 and 17 
degrees).  There is a significant NULL from 8 to 11 degrees.

When 10M is wide open my 40 ft high antenna
(with 3 dB points at 6 and 19 degrees) plays very well.

Most Europeans are using fairly LOW antennas which
concentrate most of their radiated power at higher angles.

An MUF of 50 MHz will support a 20 degree takeoff
angle on 10M.  It is highly probable you are working
them on your SECOND lobe from 11 to 17 degrees.
It is not surprising that the 7 elements of your C31XR
provides more gain then the 2 effective elements of your C4.

A 10M beam at 80 ft has a significant NULL from 11 to 16 degrees.
As I have mentioned numerous times, my TH6 at 80 ft
almost never beats my lower antennas.  For that reason,
I expect that when 10M is wide open to Europe, most of
the signals are arriving at my QTH at 11 to 16 degress
which can be covered quite nicely with a LOW antenna.

Tom  N4KG


On Wed, 17 Oct 2001 JBaumgarte@aol.com writes:
> 
> In a message dated 10/17/01 9:46:48 AM Central Daylight Time, 
> w8ik@subich.com 
> writes:
> 
> << 
>  Since the original question concerned a move from 50 to 100 feet, 
> in my >  experience a single 10 Meter antenna at 100 feet is almost
always 
> too   high to do much good.  
>   >>
> 
> Welllll, I think it also makes a difference where you are.  Here in 
> Northern 
> Minnesota I have a C31XR (7 el on 10) at 110', and a C4 (3 with 2 
> drivers on 
> 10) at 55'.  The high antenna seldom if ever is below the low one on 
10.  
> Admittedly, it is a killer antenna on 10, one that actually allows 
> me,  running 1500 watts, to often beat out stations on the east coast 
> running 100  watts to a tribander at 30'.  :-)
> 
> John, N0IJ
> Duluth, MN
> 

________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
http://dl.www.juno.com/get/web/.

List Sponsored by AN Wireless:  AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!!  http://www.anwireless.com

-----
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com


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