PPM encoder type 2 - what is SJ1 used for?

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The jumper SJ1 has been included to provide some flexibility in the way you power the receiver, servos and PPM Encoder.

  • SJ1 soldered: The +5 Volts from the receiver and the PPM output are connected. The receiver will draw
    the power from whatever autopilot board is attached to the PPM output.

  • SJ1 open (not soldered): The +5 Volts from the Servos and the PPM output are separated.
    The receiver needs an separate power source.

Note that failure to remove SJ1 can damage the autopilot’s +5v switching regulator when too much current is drawn so its usually best to keep it removed.

You can also find the manual here