Well thanks-- I'm going to have to go to Plan B with this one though. It won't happen today since it's pouring rain here, but the VSWR went nuts yesterday suddenly and the antenna went deaf. Got up on the roof, checked the external connections, yep, all good. Opened the box... black charred plastic and pieces of coax insulation, melted foam in the end of the coax capacitor that had been sealed with RTV and wrapped with several layers of electrical tape. Nothing touching or shorting-- apparently the foam dielectric of the coax capacitor can't handle the voltage. I was afraid that may happen, but figured I wouldn't know unless I tried. It probably would have been fine with 100 watts, but this is 20 meters we're talking about...
Couple of things I could do (well, three):
1. Replace the capacitor with a high voltage variable capacitor.
2. Replace the capacitor with a length of poly dielectric RG-213 or similar.
3. Ditch the voltage feed altogether and use a 1/4 wave matching section of open wire feedline.
I'll go with option 3 since I don't have a transmitting variable on hand (and they're not cheap if you have to buy them new), and since I don't have any poly dielectric coax I'm willing to sacrifice. I don't know yet whether I'll make this a vertical Zepp or a J-pole, but I'll cut up some PVC and break out some wire I have on hand and make that 1/4 wave section today in the garage.
Oh well, it was a nice 6 days with this antenna, and from what I can tell an elevated end fed 1/2 wave can be pretty effective. The notes I kept on A/B comparison show the vertical winning over the dipole most of the time. I still was not able to break either pileup to Kuwait, but those were pretty serious pileups that the 2 el yagi may not have been able to crack either. But the wire's staying where it is, and I'll figure out another way to feed it and report back here.
Interesting experiment.
Rick
