I took some measurements of my balcony, and modified my EZNEC file, adding some straight sections at the end. The goal is to make it easy to disassemble and tune, so I bought 4 cheap telescoping sections (max length 74 cm) from Amazon (4 pack for $12). EZNEC says the reflector should only be 4 inches longer than the driven element.
The idea is to have 4 identical “meander” sections of 2 inch aluminum tape wrapped around a 5 foot by 2 foot PVC frame. The reflector gets 2 and the driven element gets 2. Then there will be a 2 foot fixed section followed by an adjustable telescoping section to use up the remainder of the balcony. The telescoping section is only 0.1″ diameter but at the ends the current is pretty low so it should work fine. I will adjust my driven element to resonance and then adjust the reflecting elements two inches longer at each end. EZNEC is saying 7.5 ohms, so a toroid balun wound about 2 1/2 turns to 6 1/2 turns ought to work just fine.
I will space the driven element and reflector by 10 feet. The balcony is about 25′ off the ground facing down a 10% grade hill so this should help a bit with getting more energy at those shallow transmit angles. I will only be able to rotate it about 22 degrees unless I put up my mast, but this should get me from Australia to Nevada at 3 dB down. Should be a good starting point.
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