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[TowerTalk] Re: Quad wires

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Subject: [TowerTalk] Re: Quad wires
From: K7GCO@aol.com (K7GCO@aol.com)
Date: Sat, 5 May 2001 09:29:43 EDT
 In a message dated 5/2/01 4:42:55 PM Pacific Daylight Time, K3BU@aol.com 
writes:
  In a message dated 5/2/01 12:30:20 PM Eastern Daylight Time, 
  w8ji@contesting.com writes >  
  >  I'd bet almost zero quad wires fail from exceeding tension limits of 
  >  the wires, and most fail from flexing at joints.
  >  
   I will take the bet!
  I never had wire fail in Quad from flexing. There is (almost) no flexing 
when 
  antenna is properly strung, with just enough tension to keep the wires from 
  flopping or flexing. In the corners I use black plastic ties, wrap it 
around 
  the wire couple of times and thread it through the hose clamp, which clamps 
  to the spreader. I keep about half inch distance between wire and hose 
clamp 
  to prevent any potential arcing over at high voltage point (due to 
  capacitance). When the spreaders and wire are up, I keep pulling one corner 
  to get the proper tension, just enough not to bend the spreaders and make 
  wire nice and tight.
  
  I wouldn't use aluminum wire, copper is cheap and good.
  Wire I use is #12 or #10 house PVC coated solid Cu wire. I pre-stretch it 
  (harden) and it doesn't go anywhere after that. Originally I though that 
  insulated wire would minimize the rain static, but the difference is hardly 
  noticeable. Insulation only prevents corrosion and wire has to be shortened 
  by about 4% due to lengthening by insulation. 
  
  Properly designed and installed quad will provide trouble free service and 
  run circles around Yagis (up to 4 elements). You can have quieter reception 
  and dual polarization with one feed line. 
  That ain't no folklore, it is a proven, measured fact (not just calculated).
 . 
  Yuri, K3BU
   >>
 There are no flexing joints or arms in a quad when the wires are properly 
strung--in particular the 2 element 5 banders.  For example in the LB the 
wires pull the arms slightly to one side.  With their wire mounts there is no 
flexing.  I've seen wire mounts to the arms that had a lot of flexing and 
they failed-not the wire.  On a good wire to arm mount, no shrink on tubing 
is needed.  With tapered quad arms the back rope holds the arms in one 
position.  One find this out when they actually have used a quad through 
observation--not an opinion.  For those who are full of opinions on antennas 
they have never used I'd like to ask "Don't you ever get tired of being 
wrong?  Opinions are of value but first hand experience is better.  

I had a 5 band LB quad up with the .06" aluminum welding wire.  We had some 
ice loading at night and wind I didn't see.  Some of the wires stretched a 
little.  Copper clad steel has been bad mouthed for quads.  It has worked 
just fine for me in every application I've used it in--including quads.  I 
have a mile of it and use it wherever I can.

The DE's are all tied together on the LB and another make.  I got the same 
patterns (?) on the air as I did in Eznec.  I didn't really need a rotator as 
answers to CQDX's came from all directions.  Even with a fast rotator it was 
very difficult to center on the direction where a DX station was.  On 10M the 
free space pattern is tilted down about 35 degrees due to the unbalanced 
currents in the other DE's except the 20M DE.  Individually fed DE's with a 
remote coax switch like Antenna Mart has is the only way to go for the best 
patterns all on the horizon.  

There was a W6 who had an article in QST of his 5 band quad with all elements 
spaced 12' with individually fed DE's and he actually tuned the reflectors 
from the roof and ended up with fair performance. 

The "Ultimate 5 or 6 band 2 element Quad" will be with tapered spacing of 
about .15 WL, W2DT Handelsmans slightly rectangular orientation for increased 
gain and Cebiks 2 wire design that also increases gain that was shown in 
AntenneX Internet Mag, copper wire that enables all joints to be soldered and 
never any joint deterioration, a variable Xc in each reflector all ganged 
together to a selsyn on the mast to enable it to be quickly tuned for max 
gain or F/B and each DE individually fed with 100 ohms balanced coax to a 
Johnson Match Box that insures max power into the input of the feedline on 
any frequency and tuning.  K7GCO
 

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