Low weight, 500 foot range audio transmission

Jonathan

Hi All,

Some friends and I are working on a ham radio/ helium balloon project. We need to transmit audio to the balloon from the ground. So line of sight and less than about 500'. Xbee's, which I have, won't do audio without digitizing. Any suggestions for light weight and inexpensive audio transmission? With a decent antenna on both ends we should only need milliwatts.

Thanks!

ceptimus

Oops, never mind - I didn't read properly and I thought you wanted to transmit audio in the opposite direction.

Phil Pilgrim (PhiPi)

Look up FM wireless mic circuits on Google. There are plenty of examples, some requiring only two transistors and some passives.

-Phil

Jonathan

I didn't explain well. We need two way comms, up and down. So two receivers as well as transmitters. I was hoping there were simple RF modules available. I have thought of a scheme to use the 433mHz modules that Parallax used to sell but haven't tested it yet.

Thanks!

Phil Pilgrim (PhiPi)

Dunno how much effort you want to put into it, but you could build something around one of these.

-Phil

Jonathan

Hmm. Those look neat Phil and worth investigating. Thanks!

LA6WNA

What about PMR`s? Something simple like these: ebay.com/itm/New-Retevis-RT33-Twin-Walkie-Talkies-UHF-LCD-Flashlight-PMR446-Kid-2-Way-Radio-/322174950026?hash=item4b031f9a8a:g:GLsAAOSwvg9XdH7n
You get 500mW and ok audio @446Mhz.
I`m using PMR`s hooked up with modems on their mic inputs and speaker outputs to transmit telemetry data. Works fine.
To save weight, just remove all the plastics and just use the "things" inside the radio.