4-Channel RC Servo Multiplexer (Assembled) by Pololu

The RC multiplexer analyzes incoming RC pulses on the SEL channel, comparing them to a user-adjustable threshold (with ±64 μs of hysteresis) to determine if master (M1–M4) or slave (S1–S4) inputs should appear on output channels (OUT1–OUT4). By default, the threshold is around 1700 μs, and slave inputs are only selected when SEL pulses exceed this. The multiplexer offers a learning mode to modify the threshold and activation direction. A yellow indicator LED indicates the RC mux's state. If the RC signal on the SEL channel is lost or invalid, the optional FAILMODE jumper dictates output behavior: if left off, master inputs control; if connected, output channels go low and remain so until the SEL signal is valid again. Many servos and ESCs turn off with a constant low signal, which can be beneficial if control signals are unreliable. The RC multiplexer deems the RC signal on the SEL channel valid if it has a 10–330 Hz pulse rate and 0.5–2.5 ms pulse width. Other inputs (S1–S4 and M1–M4) have no restrictions. The master RC device's power should be between 2.5 and 16 V, capable of supplying current drawn by servos connected to outputs. The mux draws power from the VM rail connected to SEL, M1–M4, and OUT1–OUT4 channels. The VS rail connects S1–S4 inputs but is not used by the board.

• RC Multiplexer Decision Process: Measures incoming RC pulses on SEL, compares to user-set threshold (with ±64 μs hysteresis) to determine master or slave input display on output channels
• FAILMODE Jumper Action: When SEL signal is lost or invalid, this jumper dictates output behavior
• Valid SEL Signal Criteria: Multiplexer deems SEL signal valid if it has a 10–330 Hz pulse rate and 0.5–2.5 ms pulse width
• Power Supply Requirements: Master RC device power should be 2.5–16 V and capable of supplying current drawn by connected servos