DT Rx31d Receiver Unit for Servos


79.00 AUD

2 in stock


Product Name DTRx31d
Voltage 3 -10volts
Weight 0.24 grams
Length 10mm
Width 9mm
Height 2.2mm
Type Servo
Connector None
Channels 4 or 7PPM
Onboard ESC 2 x Brushed
External ESC Capable

Instruction manual

The Rx31d is a 4 channel receiver unit for use with micro servos like the BioMetal or Linear servos. To save weight it has no connectors and you can solder the servo wires directly to the pads. This also makes the unit ideally suited to extreme micro applications where weight needs to be kept to a minimum.

The main feature of this receiver is it’s ability to handle “Differential Thrust Steering”. To do this the receiver has two x 2Amp brushed ESCs onboard which can each power their own brushed motor. You can configure control of two brushless motors. The differential rates on each motor can also be adjusted.

This is a DSM2 compatible receiver unit which can be bound to a Spektrum DSM2 capable transmitter or any other transmitter which is DSM2 capable.

Outputs: 4 x Servos, 1024 step
Optional output: 7ch Sum-PPM output on 1 pin
Brushed ESC’s: 2 x2A, 64 step, 1-direction (for planes), optional ‘twin-steering’ mix
Size: 9.8 x 10.2 x 2.2mm
Weight: 0.24g
Pad spacing: 1.27mm (0.05″)
Voltage: 3-6v (see note)
Modulation: 2.4GHz compatible with 22ms DSM2 Air

This is the most simple and straight forward system to set up. Note that the Ch1 – Throttle signal output is not needed as the onboard speed controllers take care of this. Also, in the image above we have connected the motor to one of the speed controller connectors. However, it doesn’t matter which one you connect the motor to.


The configuration above is a simple set up for using differential steering with two brushed motors. Once again Channel 1 Throttle is not needed as this is handled by the onboard speed controllers. When differential steering mode is set with the transmitter, yaw is controlled by varying the power to each engine. You can choose whether the rudder or aileron will control the yaw. Normally, with this setup you would just have 2 motors and an elevator servo to control the plane.



The configuration above is an example of a simple set up for a plane with aileron, rudder and elevator controls as well as a single brushless motor. In this setup, a signal wire from Ch1 – Throttle goes to the signal port on your ESC unit. Note that power to the ESC unit may be supplied with leads from the receiver but in the example above we have assumed that the pos and neg power to the ESC unit will be supplied with leads direct from the battery.



This example shows a common setup for running a system with dual brushless motors. Note that you will also need 2 ESC units. Once the receiver has been set for differential steering by using the transmitter, the signal for the ESC units will be provided from Ch1 and Ch4 on the receiver. You can choose whether the rudder or ailerons control the differential steering. With this setup you would typically have 2 motors and their ESC units and one servo for the elevator.