In troubleshooting the matching network for my 43′ vertical antenna, I discovered that somewhere along the way, the RF-blocking choke in the matching network had overheated and melted all of its insulation off, shorting all of the turns together. I suspect that this was caused by the wiring errors I discovered earlier, but I did find references (here) on the internet saying that the 100 uh chokes from Radio Shack have some series self-resonance that cause them to leak RF through at certain frequencies.
I read elsewhere (don’t remember where) that removing the top layer of the coil can improve things a bit. So I re-wound the coil with just one layer of windings, resulting in a 50 uh coil, rather than 100 uh. The following experiment shows that the new coil does not appear to have any significant self-resonance between 1.5 and 30 mhz. However, I’m not sure the 50 uh is going to give enough inductance at 160 meters to me usable.
Anyway, here are some videos of my experiment…