1. Overview

1.1. Contacting Pololu

The Pololu RC switches allow you to turn devices on and off using standard radio control (RC) pulses. These switches can be used with standard hobby RC systems for radio-controlled switch applications. Example applications include using extra channels on an RC receiver or servo controller to turn on lights, motors, or irrigation valves.

The RC switch measures the width of incoming RC pulses and compares it to a user-configurable threshold (with ±64 µs of hysteresis) to decide whether to activate the switch. By default, the threshold is approximately 1700 μs, with switch activation occurring above the threshold (longer pulses), but the switch has a learning mode that allows you to change the threshold and the activation direction. A safe-start feature reduces the likelihood of unexpected activation on all RC switches except the RC Servo Multiplexer.

The RC Switch family

The Pololu RC Switch with Digital Output is the most basic RC switch. This extremely compact (0.4″ × 0.4″) board can fit on a U.S. dime and has two digital outputs that indicate whether the switch is active and whether the input signal is valid. (These outputs are also available on all the other RC switches.)

The Pololu RC Switch with Small Low-Side MOSFET has an integrated low-side MOSFET that allows it to drive small loads (up to around 3 A). It ships with male header pins included but not soldered in.

The Pololu RC Switch with Medium Low-Side MOSFET has an integrated low-side MOSFET that allows it to drive moderate loads (up to around 15 A) and a voltage regulator that allows more options for powering the board. The included screw terminal block makes it easy to connect the load and load supply wires directly to the board. This RC switch ships with a 1×4 terminal block and male header pins included but not soldered in.

The Pololu RC Switch with Relay features a single-pole, double-throw (SPDT) relay, allowing it to drive large, electrically isolated loads. This board also has an integrated voltage regulator. It is available fully assembled or as a partial kit. Please note that relays make a clicking sound when they are turned on or off, so the RC Switch with Relay might not be suitable for applications requiring quiet operation.

The Pololu 4-Channel RC Servo Multiplexer is an RC switch with an integrated quad 2-input multiplexer and a voltage regulator. It allows easy switching of servo control between two independent sources. It is ideal for applications in which you have two possible control sources and want to be able to switch between them on the fly. The RC multiplexer is available fully assembled or as a partial kit.

In this guide, we use the term “RC switch” to refer to all members of the Pololu RC Switch family, including the RC multiplexer.

Pololu RC Switch with Medium Low-Side MOSFET on a breadboard.
The Pololu RC Switch with Relay connected to a typical RC receiver.

Note: This guide does not apply to our older RC switches (products #721, #722, #752, #1210, #1211).