QRP transmiter with one BD139 transistor in CW 40m band. 

This is the build of one simple cw
transmiter in 7 mHz, 800 to 1000mW output power with 2 fix frequency channels.
Build it and get on the air in 30 minutes.
PS.
Do not forget to adapt the pi filter at the end for max output power. In the schematic it's 270pF but can change with the tipe of antenna you are using.
73 and see you in the log
F4ICE