12 Volts
                                        |
                                        |
                                  ================
                                  | 12 Volt Load |
                                  ================
                                        |
                                        |
                                       |/ TIP29 collector
                                       |
Prop Pin --- Resistor --- TIP29 base---| 
                       |               |\ TIP29 emitter
                       |                |
                    Resistor            |
                       |                |
                       |                |
                      GND              GND