Lining the dish and more...

I spent a few evenings adding aluminum mesh to the grid, attaching it with 28 gauge picture hanging wire. This is tedious work, but is needed for circular polarization. I hope it pays off....

Next I built a cupped helix feed, using the same helix I built a few months ago. (4 1/2 turns on a 1 " PVC pipe). I used a 17 ounce coffee can, that has a diameter of about 4 inches/10 cm. I built it ala K5OE, i.e. about 4 cm tall. The N connector is offset from the center, and the helix is flattened for the first turn to bring down the feed point impedance. My idea is to hang the down-converter directly off the N connector. I hope the can is sturdy enough for the weight !

I put a 3/4" PVC cap in the center of the can, to attach a 3/4" pvc pipe into it. Since this pipe fits in the square dipole mounting hole of the grid dish, this makes attaching the new feed a snap!

I had to slightly file down the pvc cap to allow for the center portion of the chassis N connection to fit. The cap is screwed in with two screwes, one of which goes through one of the mounting hole of the chassis N connector.

In order for the helix to connect as close as possible to the cup backplane, I also did grind down the center part of the N connector to nearly nothing using a Dremel style rotary tool.