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Discussion Starter #1
I've looked at the drawings for the 2 and 4 square Chireix antennas, both found in Holl_ands album: http://imageevent.com/holl_ands/chireix/chireixrefl
I printed the drawings, hoping to use them for construction detail. However, the text and the drawings are not in complete agreement. The 2 square Chireix has 9.75 inch sides at 45 degree angles and the overall length from tip to tip is 26 inches. The four square Chireix has 9.75 inch sides and appears to be at 45 degree angles. Overall length from tip to tip is approximately 27 inches. This doesn't add up, the 4 sq should be 2x longer than the 2 sq if they use the same angles and side lengths. It appears that 4 sqaure uses 6.66 inch sides rather than 9.75 inch sides. What is the correct length of sides on the 4 sq? Is there a gain advantage by using longer sides (9.75 inches) and a taller reflector (60 inches)? thank you!
 

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I assumed a 1"x2" Screen Grid with the 2-Square Chireix and a 2"x4" Screen Grid with the 4-Square,
which apparently led to a mistake in labeling slide#26. Here are the corrected dimensions:

4-Square Chireix - Front View
[One small box = 1 inch]
60'H x 32"W Reflector Screen

The results and 4nec2 file were not affected. They both assume 9.75" element lengths.
Thanks for taking the time to let me know so I could correct the slide comment.
 

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Discussion Starter #4
Excellent, thank you Holl_ands! Very useful data! I have a piece of 1x1 fencing that is 10 ft long by 2 ft wide. It would be easy enough to repurpose 5 ft of that screen for a reflector. Would the reflector be too narrow at 2 ft wide? Does narrowing the reflector increase beamwidth, decrease beamwidth, or have no effect? I'm planning on comparing several antennas and I want them to have relatively wide beamwith (60 degrees or more) through most of the modern US tv band. Thanks!
 
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