Turnstile Antenna for Satellites

Alright, so I'm not done with the WX Satellites yet, and to some degree I think they're a bit of a launching platform for the amateur satellites.

I'm now focused on the antenna part of the system and it seems there is general consensus that there is a step one can take before they go to Az/El rotators. That is to use fixed site antennas such as turnstile antennas, moxon antennas, Lindenbald antennas and Quadrafilier Helix antennas.

What's grabbing me for their simplicity though are the turnstile antennas. Ideally I want to build one to use for the amateur satellites, however for now I've found a nice detailed set of instructions for a WX (or 137MHz) version here. This looks like a good first one and really guides you through the harness – which is really the complex bit of this collection of dipoles. From this, I believe it should be easy to scale for 2m and then 70cm.

Although I am surprised that this guys full harness is only using 50 ohm coax – from other sources it looked like you'd need an impedance transformer and thereby possibly some 75 ohm coax. Also surprising is that he's not added any baluns in, but then this is only being used for RX so probably not as big an issue.

Enjoy!

Here's the link in full:

P.S. I was hoping the simple turnstiles would be covered in my ARRL antenna book, but unfortunately although they're mentioned there's no detail on their design. I wonder if I have to get the ARRL Satellite Handbook.
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