Date: Wed, 31 Aug 2016 13:44:25 -0400
From: "Joe Giacobello, K2XX" <k2xx@swva.net>
To: sawyered@earthlink.net
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] 6 mtr quad
I am currently using a two element duobander on 30 and 40M on a 20 foot
boom. It's almost equivalent to a three element monoband Yagi but on a
far shorter boom. Cubex's 26 foot spreaders have held up well at this
windy QTH, although the combination of ice and wind can be destructive.
73, Joe
K2XX
## 26 ft spreaders is typ for a 40m quad. Thats a whopping 104 ft of spreader
used..PER element ! Point the boom into the wind..and now all the elements are
broadside to the wind.
## 104 ft is nuts. A full sized 40m yagi element is typ 62-74 ft. Heck, a
buddys
m2 80m yagi uses 101 ft eles.......on 80m, shortened of course.
The F12 340N uses 52-59 ft long eles, aprx 85% full size, and is only 10.3 sq
ft,
135 lbs.
## One really needs a freestanding tower...or a freestanding crankup when
using quads.
Back in the 70s, I helped a local buddy install a 4 el cubex on top of his 60
ft tall rohn 25 tower.
The only way it could be done was to remove the guys at the tower..as the boom
was raised
past each guy station...pita, never again. Then the quad was mounted 7 ft up
the mast....and the
mast bent in a high wind one day. Another gong show.
## Then helped another ham with his 5 el cubex..on a 70 ft freestanding tower.
One day a 75 mph
wind comes along..and trashes his rotor..and also a spreader....at the end of
the boom on the REF..
another pita. Once all fixed, next up was a once in 20 year ice storm, with
.375 inch ice build up.
Wires broke on the 20m REF.....down it comes again. This time he used teflon
coated wire, thinking
ice would not stick to teflon. Wrong, sticks like glue, and more problems.
## meanwhile, another local, with his gem quad has snow build up issues. The
snow was packed in
super tight, where the 8 x spreaders all converge into one point. Looked like
a 1 cubic yard block of snow.
Those spreaders they use, may well have won some BS engineering award in VE4
lands years ago, but they
attract snow and ice really bad. All these guys kept a 15-20 ft long pole at
the top of the tower...so they
could climb the tower, and use the pole to smack snow + ice off everything.
## after being in on several of these up-down-up-down-up-down quad / delta
loop install and repair
efforts, I vowed to never own one. Seeing broken wires and broken spreaders
tangled up with the guy
wires of a guyed tower will make you cringe. Then u get the other issues,
like high winds..and flexing spreaders,
at which point the wire loops all go slack.
## The 2 el, triband quad was a good ant in its day. One fella here in town
worked 300 countries with his gotham
quad, and had minimal issues with it.
Jim VE7RF
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