5、OUT：Video Out, connect to the AV IN port of OSD or transmitter. “S” line is the signal output line, “+” line for all video 12V, “-” line for all video GND. When low-grade PPM signal is input, channel 1 is on and other two are off; when high-grade PPM signal is input, channel 2 is on and other two are off; when mid-grade PPM signal is input, channel 3 is on and other two are off.
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