Got a little bit more done today, but I’m on the homestretch now.
20’ crappie poles are lightweight, but they do sag quite a bit when supported horizontally from one end (10-14 foot ones don’t, which would be a big advantage to someone building a 10, 11, 12, or 15 meter beam with them), so to counteract as much of that as I could, I added a 1/8” cord support, using ½” wood dowel as a standoff:
The nylon cord is attached to the poles about 10’ from the mounting plate (photo of that later) using tie-wraps—bowline on one end, through the eyelet in the center, trucker’s hitch on the other. That arrangement worked well with the VE7CA yagi I built and was not much the worse for the wear after 2 ½ years after I took it down.
With the 20m reflector finished, the dual band driven element could finally be addressed. This is the center insulator mounted on a PVC standoff to give the feedpoint the same height above the boom as the center of the poles:
Finally the 10 and 20 meter driven elements were attached. The solder lugs were both crimped and soldered. You can see the spacing there between the 10 and 20 meter wires, we’ll see how that works out when it’s time for tuning this array. Because the 1/8” anti-sag cord was an afterthought, I mounted the dowel standoff slightly forward of the element mounting plate. This makes the driven element pull just a bit to the front when it’s under tension but it’s not too bad. Again, if a 10 or 11 meter beam were built using crappie poles, that would not be necessary.
Well, that’s the report for now. Still to come: balun, feedline, getting it in the air, and tuning. No big deal, right?
Rick