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Quads vs. Yaggi's

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Subject: Quads vs. Yaggi's
From: (Roger L. Elowitz)
Date: Fri, 27 Dec 1996 23:21:28 -0500
Hi Bob,

I've owned a MACO quad since the late 1960's. This was one beauty of a two
element, tri-band boomless quad- built on an bolted together aluminum tubing
frame and using fiberglass spreaders. I had modified the design so that it
used #10 stranded aluminum wire for the elements and fed each driven element
loop with a separate coax line through its own gamma match. 

As far as I'm concerned, I had excellent results compared to the Moseley
TA-33 I now have sitting in the place of honor the quad formerly held. Why
the change? Several reasons. First of all, a real doozie of an ice storm hit
the quad several years ago and turned it into the cutest pretzel you ever
saw. When the ice melted the aluminum and fiberglass refused to be coaxed
back into their original shapes. It was a total disaster.

A quick call to "Mac," W9GIW found that he was in a nursing home and that
his wife, Lila, had closed the business. There were no spare parts left to
replace the bent and broken ones I had and, with that, I put the remaining
few good pieces in the rafters of my garage attic for storage.

What I liked about it was the fact that, being boomless, the element spacing
was always an eighth wave on all three bands. No compromise spacing was
necessary. While it has been disparaged here on the reflector- I don't
believe that the comparison was made for using the quad vs. the yaggi at
about 10m height (33-ft). Mine sat on a nine foot tripod tower on the roof
of my two story home. At this elevation I believe the quad out-performs a
trapped triband beam. Higher should be still better.

Since I did not keep careful records I can't tell you how the numbers
compare. I had no quibble with the front to back of the quad. However, the
tuning is something else. The quad is truly the antenna to own when you want
to tinker. The Moseley TA-33 went up in one piece and there it sits. Period!
The quad was lovingly finessed on countless evenings and weekends. While it
was a neighborhood conversation piece- ( yes! It's true I was trying to
attract another giant spider to mate with the one I kept in my garage! ) the
neighbors eventually got used to it.

Also, on the "down" side of the quad, as was pointed out here on the
reflector, a more cumbersome and ungainly monster you could never hope to
assemble. There is simply no good was to move it from point A to point B.
But, once assembled in place- it does what it's supposed to do.

I used aluminum wire of a large diameter because it was light in weight and
I believe offered better bandwidth. When everyone asked about how I managed
to solder to the aluminum wire- I confessed that I treated it the same as
aluminum tubing and bolted my coax to the wire using stainless steel
hardware. It worked like a charm.

One of these day...... I'm gonna resurrect this monster. I'll add more
aluminum wire loops for some of the other WARC bands and perhaps add a boom
for either a three or four element design. Element for element, I humbly
believe it beats the performance pants off any yaggi of any design because
of the closed full wavelength element size and because it is "quieter" due
to the closed loop. 

When you're ready to dedicate a small portion of your life to tweaking and
tinkering- go for it. For low elevations, in non-icing areas and in
"lower-wind" environments- IMHO it's the antenna of choice. And for the
money.... it's criminally cheap. But what you save in dollars- you spend in
time. There simply isn't any free lunch to be had.

Good luck and have a Very Happy and Antenna Filled New Year!

Roger, K2JAS


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