Product Overview - External RC Board

For years now, our products have been separated into two distinct categories: linear actuators and linear servos. Our PQ12, L12 and L16 lines are available as a plug-and-play linear servo, whereas our P16, T16 and P8 lines require the use of an LAC board to achieve this functionality. While our LAC board is highly functional, and ideal if you want to adjust stroke, speed, or sensitivity right on the board, it can be too large for some applications, particularly for RC and Arduino users  

What is the External RC Board?

Late last year, we released a new product that solves this problem, the External RC (Ext-R) Board. The Ext-R board is an in-line, compact, simplified version of the LAC. This board has our standard RC input and position controller, making it compatible with most RC receivers, and a wide array of controllers such as Raspberry Pi, and Arduino.

Who is the Ext-R Board for?

The Ext-R board is for users who want to use RC control with models that are not available as an R-Series servo. This includes our T16, P16 and P8 lines. It is ideal for scenarios where space is limited, making a smaller board ideal. It is a good choice for users who are comfortable setting end limits, adjusting speed and other variables using their RC transmitter, Arduino or Raspberry Pi.

Who is the Ext-R Board not for?

Users who want the ability to utilize different input options such as PWM, voltage, current and USB would be better served by our LAC board. Additionally, if you would welcome the ability to adjust speed, sensitivity and set stroke end limits right on the board, and have the space to accommodate it, the LAC board would be a better choice.

How to Use the Ext-R Board

It is important that you order an Ext-R Board that is configured to work with the actuator you intend to use it with. If you use an Ext-R with an actuator that it is not configured to work with, it will not operate correctly.

The board can be powered by the 3 wire RC connection, or by connecting an external supply to the extra pins. Please note that the voltage must match the rated voltage of your actuator. If you’re using a 12V actuator, you must use a 12V power supply. For RC applications, you will likely have to use an additional 12V battery, unless you have a different 12V power source readily available.

The actuator will move to the commanded position when power and a valid control signal are applied. The control range is between 1000µs (full retract) and 2000µs (full extend). When the control signal is removed, the actuator will move to the last valid control position it received, and then enter a low power mode. When the control signal resumes, normal operation will also resume.

Should the actuator be prevented from moving, due to overloading, impacting a hard stop, or current limiting, the stall protection mode will be activated. If the stall condition remains after a few seconds, the motor will be disabled. The commanded position must be changed (by a larger increment than usual), or the power cycled to exit the stall condition.

In addition to position feedback based Stall Protection, an adjustable potentiometer allows you to set a current limit between 0A and 1A. This can help increase the life of the actuator by limiting the maximum force the actuator will generate when overloaded.

Optional Feedback Output Pins

F1 is an optional output giving access to the position feedback signal. F2 is an optional output giving access to the current feedback signal. Any connection made to F1 or F2 must be high impedance type, or actuator performance may be affected. The Ext-R is compatible with any P16, T16, P8 or L8 model ending in -P. A one meter RC extension cable, and a piece of heat shrink are included. 


We hope that this article helps you better understand our Ext-R Board and its capabilities. Our complete line of products can now be used as linear servos without the need to make room for an LAC board. If you have further questions about the board, or about our other products, please feel free to reach out to our sales department any time.

Common Questions About the Ext-R Board

Which actuator models are compatible with the Ext-R Board?

The Ext-R is compatible with most of our P-Series actuators including P16, T16, P8, L12 and L16 models. Please note that the L12 and L16 models are available natively as a linear servo. It is less expensive and simpler to order the -R model if that is an option.

Why don’t you make P16, T16 or P8 actuators as a 6V servo?

Product development is time consuming and expensive. Having a 6V model would be ideal for some clients, but we have to consider many variables including demand, development cost, parts availability and functionality when designing new products. The Ext-R board is a single product that allows us to offer this functionality to several actuator models.

Is this a plug and play product?

This product was intended for use with our P16, T16 and p8 models, which are only available with 12V input. If you’re replacing a standard 6V servo, then no, this will not be plug-and-play. The signal wire can be used as-is, but the actuator will require a power supply that matches the rated voltage of the actuator you’re using it with.

Does this board work with the PQ12?

No, the Ext-R is not compatible with PQ12 actuators. If you need a PQ12 servo, it is available as an R-Series linear servo.

What are the dimensions of the Ext-R Board?

The board measures 36mm x 15mm x 6.7mm

Where can I find additional details on the Ext-R Board?

You can view the datasheet here. If you have additional questions, feel free to reach out to our sales department , we will be happy to assist you.

Browse Actuators From Actuonix Today

We hope this article has helped you better understand our Ext-R board and decide if it is the right fit for your application. View our collection of actuators by model or industry today. As a leading manufacturer and innovator in the micro motion marketplace, Actuonix services companies big and small in a number of industries including aerospace, medical, robotics, and more. Get in touch with us today to submit an order or to submit an inquiry.