John, VK2ASU, showed a little data link he'd built at a recent home brew group meeting at Dural and I've started experimenting.
Here's the transmitter.
They only say it’s on 433MHz but mine seems to be on about 433.9112. I can pick it up on a little hand held scanner and given that there’s no antenna connected the range seems excellent. There is a plated hole to add an antenna. I make it 17cm for a quarter wave.
I’m using RadioHead’s ASK mode here.
With an arduino sketch example.
These are the modules I bought for $1 (including postage) on ebay.
Applications of such a link are things like sending back temperature or battery voltage readings from remote sensors.
My plan is to slow down the transmission rate, test on uhf and then get it to work on 40m with the Frog sounds transceiver.