I'm picking up an idea left by Dick KK4OBI, that you can lower impedance of dipole by arbitrary ratio if said dipole is zigzagged or otherwise uniformly contorted in some meandering shape. Side effect is that dipole becomes shorter and needs more wire. While there's data about impedance for fundamental, there's nothing about harmonics which is something that OCFD might be expected to handle well, so guessing that the really important part is aspect ratio of meander, i've made a couple of VHF-scale models with different meander aspect ratios (and many more much smaller sections), and some of data i've been able to collect roughly matches. The thing I'm trying to figure is what aspect ratio should be to cover multiple bands while using OCFD, say 40-20-15m bands, and whether impedances at different frequencies fall at the same rate. Eventually, when i figure this out, i'll try to make a full size 40m fundamental antenna, as I think that i've figured it out in mechanical terms
However during testing it turned out that I have severe common mode current problems, as two 10mm dia split ferrite beads were evidently not enough, so what little i've been able to collect is mostly useless. When I packed up everything I've found 4 Laird 28B beads that should together give 1100 ohms of impedance or so at 100MHz which also happens to be close to lowest frequency in my setup. Is this enough? Feedline is currently about as long as shorter arm of straight dipole at 22,5:77,5 split ratio, should I change it?
i heard a story about varnish factory that failed quality checks after one old guy got fired, he was a smoker and used to spit in the main reactor. some enzyme from saliva made it shinier