I pretty much just made this guy's Mark III antenna.
- PC board material from the local electronic surplus store
- RG58 AU coax
- SMA connector
- 1/2 inch soft copper tubing - Aircraft Aisle at the Despot
- 1/2 inch elbow
- 1/2 inch 3" long nipple
I friction fit a nut in the end of the nipple and soldered it there. Then ran a bolt up thru the bottom of the board to secure it.
I tuned it up using a SWR meter. Move the free end of the ring tube up and down and vary the position of the center coax conductor to achieve best radiation and lowest SWR.
It was a fun little project - I have about .02 aviation money units in it, so even if it failed it would not have been too painful.