Delta loop antennas have been used by ham radio operators since the early 1970′s. The antenna was built with aluminum tubing and the apex was above the boom making the antenna top heavy. This type of construction didn’t become popular as a standard antenna for the ham community because of its restrictions and installation difficulties. Now, ham operators are experimenting with the new delta loop antenna design because of its balanced design. Also, the weight is 25 percent lighter then the quad because of one less spreader making this antenna more manageable. This antenna can also be used on 40 meters as a rotatable. Now, with new polymer fibreglass support spreaders that are available, this antenna can now support larger volumes of ice and survive higher wind loads. There are many variations of the antenna as to how it is installed. I have found that with the apex at the bottom and below the boom, it can support the feedline easier and be more balanced. I have a 2 element 40 meter delta loop and have found it to be a joy because it has almost the same gain as a 3 element yagi. With proper calculations and antenna modeling, the experimenter builder can design a 7 band multi-element delta-loop antenna (10,12,15,17,20,30,40 meters) that will survive extreme weather conditions and have high gain. Now, the question is, what manufacturer has one of these antennas for sale? I would assume not many if any. We at deltaloopantenna.com manufacture 2 inch ID brackets with 1/8 inch wall. 3 inch ID is 3/16 inch wall and 4 inch is 1/4 inch wall. All brackets are made of 6061 T6 aluminum. The aluminum bracket is welded every 120 degrees and are designed to work as a boom clamp. 2 inch brackets can be used for 2 elements down to 20 meters, 3 inch for 4 elements down to 20/30 meters and 4 inch can be used for 30/40 meter delta loops. I have used 3 inch brackets for 40 meters but the boom was quite heavy being it was 1/4 inch thick. With the 4 inch bracket, the thickness of the boom can be less, possibly 3/16 inch thick thus making it lighter. These recommendations are only suggestions for the antenna experimenter.