| The results were published in a book.  Part of the book details the setup. 
Equipment used, topologies, etc. 
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message----- 
From: Peter Voelpel 
Sent: Monday, April 13, 2015 11:59 AM
To: 'Jeff AC0C'
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] [Bulk] Re: antenna choices for K4XS
Where is that supporting study?
I doubt that they measured within the main lobe of the antennas on the
comparison test.
73
Peter
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Jeff
AC0C
Sent: Montag, 13. April 2015 18:15
To: bcarling@cfl.rr.com; towertalk@contesting.com
Subject: Re: [TowerTalk] [Bulk] Re: antenna choices for K4XS
Read the supporting study - the details of the test method are explained
pretty clearly.  Then you can make your determination as to the validity of
the methods employeed.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message----- 
From: Bry Carling AF4K 
Sent: Monday, April 13, 2015 11:12 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] [Bulk] Re: antenna choices for K4XS
Very good point. I do not know whether these deep scientific studies were
done at NEAR
FIELD to the antennas or at distances of hundreds of miles away.
The articles / books claim that these yagoi beams have virtually no gain at
all. I wonder
whhow NEC would stack up against their measurements? It's in a boob, or
article so it MUST
be true. I am just left pondering the same as you - trying to decide where
ALL that extra
power is disappearing to...
On 13 Apr 2015 at 7:40, Markku Oksanen wrote:
 
On "Low Performance Trap Antennas" :  Is it really known what is the cause
 
 
for the apparently very large difference between a correctly designed trap
 
 
beam, say a TH6DXX or similar and one of the not so good performers?  Trap
 
 
loss can't be a big part because even relatively low power loss at a given
 
 
trap, say 50 W, will burn the thing very quickly.  Assume 3 elements, 6
traps that get exposed on a given band and -3dB gain compared to better
beam, this would be some 1500/2/6 watts, a lot of watts per trap.  Even it
 
 
not this much just loss, there would be ample power to melt the insides of
 
 
the trap.
MarkkuOH2RA/WW1C
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