The PPM encoder allows you to connect your PWM-only RC equipment to PPM-only autopilot systems such as the HKpilot32 or Pixhawk. Smaller than previous PPM, the encoder will enable you to reduce all your channels to a single wire, excluding ground and power lines. As a result, you’ll get faster processing and reduced points of error.
Note: onboard firmware version 2.3.16.
PPM encoder module *1
2.54 3P cable *1
Very fast response, you can't actually see any difference! You can trust this tiny device.great little device.. simple to use.. here is how to wire it up http://planner.ardupilot.com/wp-content/uploads/sites/5/2013/06/PPM-Encoder-3DR-Manual.pdf