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[TowerTalk] Quad Element Tuning

To: <>
Subject: [TowerTalk] Quad Element Tuning
From: (
Date: Sat, 8 Sep 2001 13:03:55 EDT
In a message dated 9/7/01 11:15:50 PM Pacific Daylight Time, 

 In a message dated 9/7/01 8:42:10 AM Pacific Daylight Time, writes:
 > On a 5 band 4 element quad you have 15 stubs.  Each requires lowering
 >  antenna and raising it several times.  Lots of work.
     Amen. You can burn a LOT of time twiddling with the tuning. That's why I 
 switched to yagis.
 Cheers,   Steve   K7LXC
 Tower Tech 
There is a lot of truth to this--howsomever.  This is the year 2001 and some 
creativity should come into play.  I have a wooden platform that extends out 
6' in a triangle shape supported with 2x4" and 2x2 braces that I stand or sit 
on and make all the adjustments or whatever very quickly.  You will be able 
to see this on a front cover picture on 73 mag.  I have a switch at the tower 
to rotate the beam.  I've had the rig up there also and used steady signal 
sources for F/B adjustments and some cases I did it all alone including the 
erection of the quad.  

A W6 who had the article in QST on a 5 band 2 element quad where he installed 
fixed Xc's of certain values in the reflector.  I think he had a variable for 
initial tune up and it has to be a bit longer than normal length when adding 
Xc's.  His buddy used a short tapped coil for adjustment and it has to be a 
bit shorter than normal before the coil is added.  I prefer to add 4 shorts 
to the corners instead or just adjust the entire length which requires the 
ability to rotate the quad.  It can be all done from my wooden platform.  As 
I recall he lowered a crank up tower next to the house so the reflector was 
near the roof where he stood and made adjustments.  My next 5 band 2 element 
quad will have variable Xc's in each reflector all ganged together on a shaft 
going to the mast driven by a selsyn driven by another at the shack.  I'll be 
able to adjust for max gain or F/B within seconds with a pointer on a 360 
degree dial--all over the band and on each band.   

The adjustments on yagi's are on the ends and that takes a much longer 
platform which is not practical.  In 1956 I came up with a mount for the boom 
to the mast that permits tipping and twisting of the boom in such a way the 
tips of any element could be brought right into the tower for easy 
adjustment.  When installing the beam the boom is first installed.  It's 
tipped to the tower and a reflector is pulled up by rope and is installed.  A 
rope tips the boom back to the other side of the tower and another element is 
added.  The boom is leveled and the DE is installed.  I've installed 20M 
beams in 20 minutes time all by myself in 20 MPH winds with just a street 

I like tip over towers properly made as well as the tri-ex telescoping masts 
with the platforms.  Use one of these towers for initial tune ups and then 
transfer it to the final tower.  There are many ways to solve all these 
problems.  Antennas all require maintenance at some time and this sometimes 
has to wait until spring for many.  I've been able to make adjustments or 
repairs safely in 10-20 minutes year around with the platform and my "One Man 
Universal Joint Mount".  It was written up in CQ about 40 years ago and is 
for 2-4" booms.  It just took a hack saw and a drill to make.  

Being able to work on your antenna quickly is still a must.  Many have the 
total misconception that I'll install this sucker and that's it.  That's true 
more now today than ever before.  Some are computer tuned and even I would 
have little reason to change them other than mechanical deficiencies that 
some still have to save you money.  There are some Antenna Mfgs without 
antenna software.  They rely on your inability not to detect the design 
deficiencies and their lower price and they succeed. Then the Reflectors are 
full of questions and Band aid repairs.   

Quad designs haven't been finalized as much today but will shortly.  The 
initial Quad Junk Dealers years ago crippled quad designs and hampered quad 
popularity except for those who did it right in recent years like Antenna 
Mart.  There were a lot of Yagi Junk Dealers in the past also.  Variable 
capacitors remotely controlled give great flexibility and is a design of the 
future (actually been used for years). 

A well designed 40-50 tip over or crank up is a good investment for every ham 
whether you can climb a tower or not.  If a big storm is coming you can get 
it down quickly.  A wooden platform is a must.  I can still climb but I'd 
rather not.   k7go

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