Ham radio HT CW transceiver project from WhiskeyTangoHotel.com: Really not much explanation needed; just connect as shown above. This project uses an electronic keyer, but a simple straight key/oscillator combo could also be used. Oh… and you will also need to know Morse Code.
echOs built a CW(Morse code) transmitter using a TI launchpad with a minimal amount of components. Only capable of low power transmitting, this would be use full for finding that lost high altitude payload, or fox hunting. Via: Hack a Day