In Reply to: Need help in RF circuits. posted by Imdad Saiyed on 03/25/03 at 12:01 PM:
You might want to check this website. Won't get much from it though, as it is mostly in chinese. You can however try to e-mail them.
For ready-made RF modules, try:
You will need to interface the modules to microcontrollers, but they are generally quite stable. Range is quite small though (about 300' or so).
Hope this helps,