VOR -speak

[doublescan]

I learned something a few days ago about the am airband that I never thought about-some of the VOR sites transmit voice signals! Just happened to be standing in the yard with a newly-built dipole, waving it in different directions when I happened to hit the Search button on my old handheld. It started searching down from 122mhz and stopped on a fairly good signal at 114.400. With a voice recording about weather.
Rarely I can get the ATIS from Bham airport on 119.400, due to all the mountains around me, but this was much better signal. BUT, the dipole has to be horizontal to get it, turning it to vertical and no more signal.
Now I'm making a dedicated dipole for horizontal listening, haha. If you are curious like I was, look up Vulcan VOR on the airnav website, the hazard weather recording is called "HIWAS" if I copied right.
Maybe my mountains are changing the polarity to "H" for me on this transmission, all the other stuff on aircraft comes in fine with the antenna oriented vertically. What a fun hobby!

 

[autovon]

You can also look on the VFR charts and on the VOR frequency box, there will be an H in the top right corner showing that the particular VOR has HIWAS. I think even a new NDBs have HIWAS, although I imagine that is getting pretty rare.
There are also select VORs where you can use them to talk to the Flight Service station. For example, you can do it on the Vulcan VOR by transmitting to Anniston Radio on 122.1 and tell them you're receiving on the Vulcan VOR. They should reply on the VOR freq.

 

[Discriminator]

Maybe my mountains are changing the polarity to "H" for me on this transmission, all the other stuff on aircraft comes in fine with the antenna oriented vertically. What a fun hobby!

VOR stations use horizontal polarization - https://sites.google.com/site/logancte/module-2

-Rene

 

[doublescan]

h-signals

Thanks Discriminator, some highly technical information in your link-thanks!

 

[k4pbn]

The VUZ VOR is located on Crocker Mountain between Mt. Olive & Brookside

 

[navaidstech]

Doublescan, if you more or less line yourself with a runway that has an ILS, you will also be able to pick up a Localizer somewhere between 108 and 112 MHz. Also horizontally polarized but much lower in power than a VOR = additional challenge!

 

[nr2d]

VORs as stated above are horizontally polarized. A VOR uses an antenna system call an Alford Loop. There are versions of this antenna, conventional and Doppler. Doppler VORs are found generally in areas where it is necessary to have a VOR to support Air Traffic but due to the surrounding environment a conventional VOR would have too many reflections to be usable. The VORs at LGA and DCA are Doppler VORs. The basic difference is how the navigation signal is developed in the Doppler VOR.

When I flew as a technician in FAA Flight Inspection we had to perform a test looking for the vertical polarization component of the VOR’s antenna. If it was greater than a certain value, I forget the value though, the VOR would be shut down.

Localizers and glide slopes that make an ILS system are also horizontally polarized.
Power outputs of the 3 systems are about 150 watts for a VOR, 10 – 15 Watts for a localizer and 3 watts for a glide slope.

If you look at my avatar it is a spectrum analyzer display of what the RF spectrum of the course transmitter looks like of a capture effect localizer on the localizer center. The middle signal is the localizer carrier, the 1st 2 signals to the left and right of the carrier is the 90 Hz modulation and the 2nd 2 signals left and right are the 150 Hz modulation.

 

[doublescan]

vor speaks

Thanks for all the good info>I wondered where the VOR was located, I get best signal when aimed SW, so from where I am, so I know it's not a reflected signal off the mountains here.
I read a bit about the Alford loop antenna, interesting as it seems to be able to transmit both horizontal and vertical, at once. Have to research scanner antenna projects now to see if there are any that do both pol at the same time, I lose this signal when I rotate the dipole to vertical, but of course can still get plenty of planes in flight. I'll have to try for one of the localizer signals next, haha but that will be a real trick from 20+miles.