Howdy, We had a great net today. Big John was not heard. Maurice was kind enough to step in.
In a clear display of enlightened, self-interest, Maurice asked us, "What would it take to get you to serve as Net Control?" Great topic! I don't think anyone volunteered. Many thanks to Maurice for covering today and all the other times he has! Jim, WA5JIM, hit on a favorite topic, "2 meter antennas in a HOA." Lots of good discussion there! In the subtle workings of Jim's mind, he came up with hanging Yagi antenna elements from the handrail of his upper deck. Great idea! Materials came up. We quickly tossed out bailing wire, as it was too hazardous for the installer. Big John's favorite, electric fence wire, popped right up. The first variant, aluminum, was dismissed, due to Jim's proximity to a corrosive body of water. The next option, galvanized steel wire, is my personal favorite. The Home Depot has a 200 foot bundle of 16 gauge galvanized steel wire for the low, low price of $9.38. Amazing. See: https://www.homedepot.com/p/OOK-200-ft-55-lbs-16-Gauge-Galvanized-Steel-Wire-534806/100141392 We also brainstormed properties of wire. Measuring out two times the required length, folding in half, chucking the middle into a drill, and twisting two pieces will make a stronger, thicker element and provide more bandwidth from the antenna! With materials picked out, the discussion turned to installation. Jim's idea was to tack the Yagi beam elements to the handrail, eliminating the need for a boom! This limits him to a vertical beam, but is still a great idea! The Reflector and Driven Element will stand a bit proud, but the Directors (as many as you want) can be tacked directly flush to the handrail. Imagine six or eight Directors. Each Director added narrows the beam angle. Hum. The antenna farm is north and west of Jim. Maybe too many is too much... Using all available handrails, he can build a north facing beam along with west and south. East of him is the Gulf. NIST Technical Note 688 <https://tf.nist.gov/general/pdf/451.pdf> tells us the following: - Wavelength [image: image.gif] : 300/(Frequency in MHz) - Driven Element (Dipole): 0.5 * Wavelength - Reflector Length: 1.05 * (0.5 * Wavelength [image: image.gif]) - Director Length (as many as you want): 0.95 * (0.5 * Wavelength) - Spacing: 0.2 * Wavelength Easy! An important feature to add is the hairpin match. An 8 inch length of common wire is bent to a 3" x 2" U shape and is attached at the feed point of the Driven Element. This brings the impedance and SWR in line. We eagerly await photos and success stories! 73 Dan KJ5IZK
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