Never stop developing or improving. My goal is a system I can quickly mount/unmount with a AZ rotor for Rover contests and then remove the horizontal antennas and bolt-on an EL rotor and satellite (or EME?) antennas. Basically a modular system that can perform VHF contesting or Satellite contacts (on the car or in the back yard).
This redesign required I move away from the PVC and wood shelf to a more versatile and strong steel base. To add a rotor I would also need a thrust bearing with some way to support it and I would need to mount all the horizontal antennas to one mast. The other problem is that I need to keep the weight down as the car roof load limit is 300 lbs not to mention I have to be able to lift it on/off the car roof myself. Further, the little clamps of the roof rack I assume have some limited amount of clamping force that cannot be taken for granted.
I call this a brute-force redesign because it’s had several different trial-and-error periods. For example, I was hopeful to use the telescoping carbon fiber mast but the antenna mounts squeeze the CF mast and prevent it from telescoping. If I loosen them enough to allow telescoping of the mast then the antennas can move around the mast just from wind. I then tore it all down and switched to a 1-1/4 inch steel electrical conduit and I had hoped to use a 1-1/2 inch PVC X junction as a mast bearing but I fear this could shatter if I had to hard brake. Also I’m concerned the PVC may give no warning of eminent failure. Eventually I found that I could insert sections of the telescoping mast inside the 1-1/4 electrical conduit so that’s what I’ve landed on.
Next I will add the AZ portion of the AZ/EL rotor which will require 3 or 4 more struts as legs to the Yaesu GS-050 thrust bearing which will hold a 1-1/4 inch steel conduit that the antennas will be mounted onto. I will mount the heaviest at the bottom (2m) then maybe a T-cross to mount 23cm and 70cm Yagi. Above that maybe the 1.25m Yagi, On the telescoping mast inside I will mount the 6m loop or 6m Moxon. This will hopefully minimize the top heavy problems in the event I need to hard brake.
More to come… but for now this is on hold… too many things going on and the summer heat arrived early.
