A Successful Alternative to the Cubical Quad
he revolutionary antenna you see pictured, the E-Z-O, was created by N8PPQ as the result of his efforts to reduce the cost of a longtime favorite, the cubical quad.
The idea came after a Scouting event, and was inspired by the way tent design has changed, with flexible tubes replacing ridged poles.
Cost savings were significant, but the design has several other advantages. The antenna is much lighter than a cubical quad. It also presents less surface area for wind and ice loading. Stresses from gusts are relieved because the elements are not rigidly fixed to the boom. All this allows for a smaller and cheaper boom. And it is easy for one person to install. To top all that, this antenna even performs better than a cubical quad! The square loops of a quad admit to being only approximations to their theoretical ideal: circles.
In spite of its humble inception, this could be the biggest improvement in antenna design in over 50 years!
The most fascinating part of a ham radio station, for me, has always been the antenna system. I have installed sophisticated antennas for clubs I belong to, but my personal station has only used some type of wire. That changed last summer.
While trying to reduce the cost of my longtime favorite, the cubical quad, I created the antenna you see pictured. It is a radical break from convention designs. (Patent Pending)
I wanted to save money. Spreader arms and “spiders” that attach them to the boom are expensive. I recalled the way camping tents have changed, with flexible tubes replacing ridged poles. I imagined that fiberglass tubes could support the wire elements of a quad more cheaply. I was right. I saved money with this design.
But I discovered several other advantages. The antenna weighs much less than a quad. It has less surface area for wind and ice loading. Stresses from wind gusts are relieved because the elements are not rigidly fixed to the boom. The lower stresses allow for a smaller and cheaper (2″) boom. Further, one person can install this antenna with no need for a crew of helpers. And to top all that, it even performs better than a quad! The square loops of a quad admit to being only approximations to their theoretical ideal: circles!
Another surprise was the positive response from my neighbors. People smile and ask what it is. When I tell them it’s a ham radio antenna, they congratulate me. Other antennas, with sharp protruding angles hoisted above the boom, have elicited fear and skepticism. Evidently these thin circles suspended below the boom are not threatening.
This antenna shares the positive characteristics of a quad. For example, radiated signals do not couple with the tower. That is because when fed from the top, the E-Z-O Antenna is horizontally polarized. And since quad antennas characteristically propagate at low angles even at heights below L/4, suspending the E-Z-O below the boom is inconsequential for most tower heights.
I am primarily a DXer. My biggest concern is being heard over the pileup. For that, I need gain. The 3 element E-Z-O gives 15 dB over my G5RV, which is no slouch itself having earned me 235 DXCC’s during this sunspot minimum.