Radio system

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Preparing the transmitter

The AR7210BX receiver can be used with any Spektrum DSM/2 or DMSX compatible air radio system. To make the radio link more robust you can connect an additional Spektrum DSMX remote satellite to the AR7210BX receiver. Especially this is recommended when used on helicopters larger than 500 size. Big helicopters allow to fly further away and have more physical mass. These two circumstance can cause radio interference more easily. On one hand it is more likely that there is no direct line of sight to the antennas of the receiving unit, which on the other hand can be critical the greater the distance between transmitter and receiver is.

Please note when attaching a Spektrum remote satellite this must be of DSMX type. Do not use an older DSM2 remote satellite receiver!

  • Create a new model in your radio‘s model memory.


  • Never enable your radio‘s eCCPM mixing function! Disable any mixing functions for the swashplate or rudder. Each function should be assigned to just one receiver channel. All the swashplate mixing will be done by the AR7210BX receiver. Set your radio‘s swash mixer to mCCPM (mechanical mixing) which is often called “H1”, “1 servo” or “normal“ mixing or disable “swash mixing” if applicable.


  • Be sure that all trims and sub trims are disabled and that all servo travels are set to 100% in any flight mode. There mustn't be any active mixing functions (for example rudder revo-mixing). Have a look at the radio’s servo monitor: each stick has to control one channel/servo output (except for thrust stick which typically controls collective pitch and motor). Note when using MICROBEAST PLUS you do not directly control the servos of the helicopter. By moving a stick you give a control command to the system which then performs the necessary servo movements to move the helictoper in the commanded direction. Each control command is bound to one servo output channel of the transmitter.


  • Also do not adjust the collective pitch curve at the moment. For the setup procedures it has to be set as a straight line reaching from -100% to +100% (or 0 to 100% depending on radio brand).


  • Other functions such as throttle curves, ESC switches or auxiliary functions can be adjusted as usual. But especially for the throttle make sure you can disable the throttle channel and separate it from the collective stick movement for performing the setup. You can do this by using the HOLD switch on the radio or by setting the throttle curve to a flat 0% line. Also it is advisable to create different flight modes for different flight states/rotor headspeeds.



  Make sure that the motor in electric models can not start when doing the adjustment work! In case the drive battery is used as power supply for receiver and servos, disconnect the motor from the ESC.




Receiver installation

In the following you can see the wiring scheme. Ensure a tight fit of the connectors and make sure they are fully inserted. If you have the feel that the plugs can come out quite easily they should additionally be secured against loosening.


Receiver binding

Prior to use you must bind the receiver to your Spektrum radio system. Please note that when you AR7210BX was already bound to your radio earlier, you must rebind when you connected a remote satellite afterwards (even when the satellite also was bound to your radio by another receiver)!

  • Insert a Spektrum® “Bind Plug” at the [SYS] port of AR7210BX. In case the power is supplied exclusively at the [SYS] connection, to bind a Spektrum® satellite receiver the power supply must be provided temporarily through any of the other ports.


  • Make sure the throttle on the radio is in lowest position. When bind procedure is finished the AR72100BX will store this position as Fail Safe position, which means that the throttle will moved here in case the radio link is broken before or in flight. Also this position will be used to prevent from powering up your radio with full throttle engaged by accident. So later onwards you will always have to make sure the throttle is at this low position when powering up radio and receiver (Smart Safe).


  • Switch on the power supply now and initiate bind sequence on your radio system (usually by pressing and holding the bind button on the radio and powering up). After successful binding procedure the system will start with common initialization sequence. Additional note: It makes no difference if you pull off the “Bind Plug” during the binding process or leave it connected as you would expect from other Spektrum® receivers!


  Watch out that the motor can not start accidentally when using the BEC of your speed controller to power the unit!