[TowerTalk] quads
Alan Gray
agray@voicenet.com
Fri, 26 May 2000 11:48:28 -0400
Dave-
You say: "Dunc even helped K3MBF [ex-W6SAI]design his 2 el 75 quad that was
featured in QST mounted as part of his Telrex christmas tree array on a Big
Bertha rotating tower."
Just as a point of reference, I believe that the Bertha you are referring to
was the one Joe Hertzberg (K3JH and later, N3EA) had in Bryn Mawr, PA. By
the way, Joe's tower, like all Bertha's, was actually made by Lingo, Inc.,
not Telrex. And Joe's antennas weren't Telrex either, they were the
"original" Hygain Long Johns- the big commercial models (same ones the K7UGA
had on his Hygain RP-100 pole).
Alan, W3BV
----- Original Message -----
From: <thompson@mindspring.com>
To: <towertalk@contesting.com>
Sent: Thursday, May 25, 2000 01:18 PM
Subject: [TowerTalk] quads
>
> The discussion seems to have gotten around to quads and it seems they take
a
> bad rap every time.
>
> My first quad was the awful Skylane 3 element tri-band quad. The boom was
> ribbed aluminum and if you stood on it
> flattened out (like the old Gotham beam series). As awful as it was it
> worked fair on 10 and 20 but was a real killer
> on 15. I could work JA's from Eastern W5 even over such contest stations
as
> W6RW and W6HJT (later K6PU). Boom length was 16 feet. My only comparison
> was the old Gonset Tri-bander modified to W1PDF and W1ONK specs. Boom
> length was 18 feet. This antenna was a killer on 20 during the ARRL SS
but
> was only fair for DXing. The Skylane was about the same on 20 and 10,
but
> was far superior on 15. The rub was the beam stayed up and the quad blew
> off in a spring storm.
>
> My next quad was the W5HVV/7 version in QST in 1966. This was a 3 el on
20
> and 4 el on 15 and 10 on a 20 foot boom. This was an improvement on 20
> and 10 over either of the previous antennas. On 15 the W5HVV was the
equal
> of the Skylane. Even though this antenna was heavy, well built, and I
had
> the assistance of a mechanical engineer the W5HVV disappeared in another
> spring storm into the Bayou behind the house. The mast snapped off just
> above the rotor so any antenna would have probably gone into the wind.
> I had a Mosley TA-36 and for two years I used this with a 40 meter
> extension. The Mosley did not even measure up to the Gonset beam except
on
> 10 where it worked very well. All the above antennas were at 49.5 feet
on
> a telephone pole.
>
> I moved to another nearby city and got both a 71' crank up (still use) and
a
> 4 el GEM Quad. I was disappointed in the GEM Quad as being mounted on a
> metal tower detuned the antenna on each band. The Dx gang in the city
told
> me the only partial remedy was to
> get the quad above the metal tower. W5AO (EX W5CKY) got me a 15 foot
> piece of aluminum thick wall mast and putting the antenna 10 feet above
the
> top of the tower did improve front to back but not performance. With
> W5AO's help we measured front to back as minus on 20 and 15 and 5 Dbd on
10.
> Raising the quad improved this to 6 dbd on 20 and 15 and to 11 dbd on 15.
> This was measured at 250 feet with a commercial field strength meter with
a
> Db meter (Motorola). I watched the quad through Hurricane Camille and
> became so worried that back up went the TA-36 and 40 meter extension.
>
> During this same time frame Dunc Carter W5IOU was building his big quads
at
> his station and W5WMU. Dunc swore by big quads
> (multi element on Rohn 25 booms). Dunc even helped K3MBF design his 2 el
75
> quad that was featured in QST mounted as part of his Telrex christmas tree
> array on a Big Bertha rotating tower. Funny, W5WMU really liked the
quads
> but living in South Louisiana took its toll and he switched to long boom
> yagis.
>
> Recently W8JI pointed out that the quad does not exist in commercial and
> military applications (99% yagi). The only place I saw quads was at
Mitre
> Labs near Boston. They are non-existent in military installations which
do
> often have curtain arrays or Yagis.
>
> The first real bashing of the quads was done by N6NB (Ex K6YNB) in the
early
> 80's. Others like K4JC could not tell ant difference between a 5 el mono
> bander and a 4 el quad on 80 foot telephone poles. So I guess the bottom
> line is Quads and Yagis are both high performance endfire antennas. The
> place where the quad (loop) shines in that it is better than a yagi dipole
> (single element). W7RM uses his 160 loop on all the bands and it works
very
> well. The construction required for a quad or delta loop is more
rigorous
> than for a yagi and both work very well when tuned and matched.
>
> Dave K4JRB
>
>
>
> --
> FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
> Search: http://www.contesting.com/km9p/search.htm
>
>
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm