Hi Ed -
If we're collecting antidotal evidence - I use 160m quarterwave slopers (140
feet) fed at the top of a 100 foot tower and also, for general purposes,
have six 100 foot raised radials around the base of the tower. The 160m
quarterwave slopers are also 80m reflectors working with my three 80m bent
vertical dipoles. I have three wires up there and can pick one at a time or
leave all three floating (on 80 m). On 160m I didn't try to tweak the
antenna to a good SWR, I just inserted a little L network in the feedline
at the base of the tower. The results have been very good (on 80 and 160).
The biggest problem is that when running 1.5 KW I can be heard much better
than I can hear. I'm listening on a pair of phased pennants (selectable in
four directions) - no room for beverages. (But then, You've already got
"EAR" 's.)
My guess is that a few raised radials, especially right under the slopers,
might be good.
Good luck with your project.
Gene / W2LU
----- Original Message -----
From: "K8RI on TT" <k8ri-on-towertalk@tm.net>
To: <towertalk@contesting.com>
Sent: Tuesday, September 13, 2011 7:27 PM
Subject: Re: [TowerTalk] 1/4 slopers & Radials
> On 9/13/2011 5:37 PM, Ed Richardson wrote:
>> I know that many of us surbanites use slopers for our low band antenna
>> component. There also seems to be some contradictory advice on the need
>> for radials on these antennas.
>>
>> Has anyone ever made any real world measurements on these antennas, with
>> and without radials, and how performance may be impacted?
>
> I've never run any comparison, but I understand the half sloper works
> against the tower, not the other end.
> I've had good results with a half sloper on 160 fed near the top of a
> 100' 45G.
>
> http://www.rogerhalstead.com/ham_files/tower44.htm
> http://www.rogerhalstead.com/ham_files/tower45.htm
> http://www.rogerhalstead.com/ham_files/tower46.htm
> http://www.rogerhalstead.com/ham_files/tower46.htm Set up shown near
> base of tower.
>
> 73
>
> Roger (K8RI)
>
>>
>> Ed VE4EAR
>>
>> _______________________________________________
>>
>>
>>
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>
>
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