W4SDR 432MHz EME Az-El-Pol 3-axis mount.

You can loose a lot of signal if your polarization isn't matched to the incident wave.
One way to match the wave is to assume it's ether in the vertical plane, or the horizontal plane.

So - use one set of antennas for horizontal, and another for vertical.

But - you're only able to use half of your antennas a time.

And what if the Faraday rotation is somewhere between horizontal and vertical?
You still operate at a loss.

I thought that a continuously variable polarization mount could reduce such losses, and allow me to use all antennas in a variable plane.

This prototype shows the proof-of-concept for the 3-axis mount.
Currently, it's flipping just one M^2 432-9WL yagi.

Do you need more than one long yagi for EME? Yes - it would help if there were a lot more!

And the design can be scaled up to a larger array of antennas to increase the aperture.

Theory says that I should only need half as many antennas than a fixed H and V mount.

The yagi is hanging out in free-space, in terms of the 70cm wavelength.
The support arms are 1.25 PVC. Each is about 180cm from the mass of the rotors.
I need some Fiberglas or FRP tube to reduce the bend moment.

The green box is just a Tupperware tote that I hoarked out with a RotoZip to fit around the mount.
I know the rotors can be left out in the weather.
But why not protect them anyhow?
The tote isn't a sealed box that might retain moisture.
Rather, it's just a rain guard for the preamps, switches, shaft bushings, connectors, and blocks UV from baking the units.

Are there other ways to rotate polarization? Of course. This was done with items I had on hand.

Category:

Education

Tags:

• Ham
• Radio
• EME