Jay, one of the coax connectors is the feedline. The other is a coaxial capacitor. You can see it better in this photo of a Cushcraft AR6.Yo HomerBB: Looking at the first two photos you shown. the top photo looks like theres two connectors there, what is that for? The photo doesn't show all.
I like your Quad Hub design, I rebuilt a few Moonraker 4 Beams for friends, and had to have the old original cast Aluminum Hubs replaced with new billet machined ones for not cheap. But bullet proof.
The old PDL-II two element quad seemed to work well, now you got me going on a Quad design...…...
Jay in the Great Mojave Desert
The old PDL-II two element quad seemed to work well, now you got me going on a Quad design...…...
Have some of that. Been pondering using it. Harbor Freight has some cheap o stuff, but not all that thk. May try sliding some over a PEX bushing I cut to fit the fiberglass rod, might work.