TenTec
[Top] [All Lists]

Re: [TenTec] vertical radials

To: tentec@contesting.com
Subject: Re: [TenTec] vertical radials
From: ac5e@comcast.net
Reply-to: tentec@contesting.com
Date: Sat, 05 Jun 2004 17:12:09 +0000
List-post: <mailto:tentec@contesting.com>
Mike, that's sort of a sore subject around here - and one of the major 
considerations in deciding to finally build the new house and move to the farm. 
Where my neighbor the alderman won't have a word to say about my antennas! 

>From my operators chair, where 160 is usually wrapped up in static, a 
>shortened vertical is less than satisfactory on Top Band.  The advantage is 
>they are vertically polarized, so your signal is not  snatched up by the 
>geomagnetic field and taken for a free ride to the center of the earth. 

The disadvantages are first, the feedpoint impedance of any of the shortened 
verticals is very low, making them a pain to match over more than a very narrow 
frequency range.  They are highly reactive, complicating the matching problem. 
And whether it's ground loss or "excess near field radiation due to  reactance" 
they don't have the field strength a few wavelengths away the formulas and 
computer simulations say they should.  

The Hy Tower is a good 75/80 Meter antenna - I had a most pleasant conversation 
with an EI one morning with 5 watts SSB - so would have no qualms about 75 
Meter QRP.  I just wish it were a better 160 antenna. 

But if you must, you must! Quarter wave radials are plenty long enough, and I 
would suggest you get a radial plate from Array Solutions or DX Engineering.  
MIG welder wire works extremely well for radials, and since so many conductors 
are in parallel any losses are strictly negligible. The stuff is strong and 
it's cheap at Harbor Freight.  Use SS washers under the screws on the radial 
plate and take an extra turn for luck when you tighten the screws down. 

73  Pete Allen  AC5E
--
Never squat with your spurs on



_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec

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