Turnstile UHF RX antenna tutorial

[IBCrazy]

I thought a perfect sphere was impossible to create. But I guess that's why you say "near" perfect.

So does this mean diversity antennas are no longer needed? No nulls to worry about. But do you still have polarization issues when the airplane is banking?

It is NOT impossible. In fact, I already designed one with a perfect spherical pattern. It's called the Caltrop antenna which is circularly polarized too. Unfortunately it's large and unweildy so it is best used in ground applications.

This antenna was designed as a substiute for diversity. If you turn your TX antenna to the side rather than upright, this will match the polarization fairly well even when banking. Horizontal polarization of the TX antenna actuall gives longer transmission range. It's also nice to know you have no nulls to worry about either

-Alex

[twinturbostang]

Very good!

I'm guessing that you have to sacrifice something in order to get CP and no nulls. So I'm assuming that you end up losing some ultimate max range (correct me if I'm wrong though). Interesting though... I wonder how well one of the UHF systems with dual antennas would work with a standard dipole on one input (for max range) and a turnstile on the other (for no nulls or polarization issues).

[airbagit13]

Well done! That antenna looks pretty damn sexy. I will definitely be building one of these bad boys when I get my Dragon Link.

[IBCrazy]

Very good!

I'm guessing that you have to sacrifice something in order to get CP and no nulls. So I'm assuming that you end up losing some ultimate max range (correct me if I'm wrong though). Interesting though... I wonder how well one of the UHF systems with dual antennas would work with a standard dipole on one input (for max range) and a turnstile on the other (for no nulls or polarization issues).

Actually, you get LONGER RANGE out of the turnstile. It's win-win

[Trappy]

this antenna looks fantastic. I love the horizontal mounting, which makes it perfect for embedding in a wing. could this be re-designed to work at 2.4GHz for transmitters, too?

[IBCrazy]

Yes it could, but the wire gauge would change as well. I can see if I can redesign it for 2.4GHz. it will have to be a ground-up design as EVERYTHING changes.

Also, you have one coming to you, Raphael. I figured you'd want to try it out along with your new BluBeam antenna set

-Alex

[Trappy]

ok. I'm very interested in these horizontally mounted antennas. will give the one I have coming a good test. it'll be pretty simple to do too, since I have diversity and can compare immediately to the "sander-style" antennas

[IBCrazy]

Awesome! I'd love a good side by side! I have a few out for Beta testing right now. You are one of them

-Alex

[Trappy]

my postman has made a regular stop here every day since 2 weeks. let's see if I can keep this going. hahaha

[SENTRY]

Well Alex you already know I've been looking for horizontal antenna... so thanks for this one. I'll led you and the Mad Austrian work out the kinks - but I'll be grabbing one soon.