The PPM Encoder plugs into the PWM servo output ports of any R/C receiver and encodes them into a PPM pulse suitable for many autopilots (e.g. Pixhawk). Modifications to the R/C receiver are not necessary. The whole project is based around the ATMEL ATMEGA328p AVR processor and all timing is done within interrupts so accuracy and stability is optimized. The design of the PPM Encoder is based on the Paperazzi PPM Encoder. Important Note: The firmware comes pre-configured to read 8 Channels. In case you would like to change the settings of the PPM encoder to invert the PPM signal and change the fail safe pre-defined values you will need an AVR ISP programmer in order to reprogram it. The jumper on the board no soldering default. In this case the board powered by FC Colour:Black Material:Composite Materials Package Contents: 2 x PPM Decoder Board 2 x Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.