Helicopters with Tail motor

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For tail motor driven helicopters, there is a separate firmware available which takes the special features of a tail motor system into account. You can download the firmware via StudioX app by activating the "Tail motor" feature on the firmware update page. Please note that all data on your Microbeast will be reset if you install the "Tail motor" Firmware over the "Standard" Firmware. Also note the "Tail motor" firmware can only be used in conjunction with a sum signal receiver. The tail motor is activated by Microbeast from the throttle signal position or from the MICROBEAST governor function. This is only possible using a sum signal receiver.

Attention! Please remove the main rotor and tail rotor blades from the helicopter in order to perform the update procedure and for further settings. There are some safety features integrated to prevent the motors from starting, but you'll never know...


After the update/reset: The firmware is preset so that it fits the Logo 200 / OMP M2 heli. Nevertheless, go through all the setting points step by step even if you're using one of those helicopters. In particular, the radio setup and the motor switches still need to be set correctly.


Receiver menu

If you haven't already done so, first start the receiver menu/remote control setup via StudioX or directly on the Microbeast:

  • Scan for your sum signal receiver, then assign functions by manual teaching or simply by loading the preset. See section ReceiverType for further instructions.
  • The telemetry setup can be skipped if necessary.
  • The "Motor off" / Failsafe position is crucial. Make sure to perform this step properly, otherwise the MICROBEAST will not know where the radio's "Motor off" position will. With tail motor this important to set correctly because the tail motor will only switch on when throttle is above 25% from lowest position!


For the Logo 200/OMP M2 heli the "Motor off" position must be around -1800. In order to reach this position, you usually have to turn the throw of the throttle channel on the remote control to -110 to -120%. During adjustment, the motor controller should arm and beep when the position is actually reached.


Governor menu

Now briefly open the Governor menu and check the settings:

  • For the Logo 200/OMP M2 heli we use the "Electric" Governor with signal divider "12" and gear ratio "1.0". If using a different heli you may change this as needed. Of course, it's also possible to do without Governor function, i.e. when your heli has a speed controler with decent internal heli governor.
  • On the next page teach idle position, which usually must be the same position as the Failsafe setting for Motor off.
  • Adjust full throttle accordingly. For the Logo 200/OMP M2 heli just give it full throttle; +100% in the transmitter should be fine.
  • Then go to "Transmitter test" and adjust the throttle curves in the radio to straight lines or setup the throttle switch so that the desired speeds are displayed. For the Logo 200/OMP M2 heli we recommend a speed of 3500rpm for Idle 1 and 4500rpm for Idle 2.


Basic heli setup

Now switch to Basic heli setup:

  • For the Logo 200/OMP M2 heli installation position should be pointing backwards. There's no other way because of the cables!?
  • The small servos usually handle a swashplate frequency of 200Hz quite well
  • You can leave the tail frequency at 333Hz for best performance. Today's motor controllers usually can handle this without problems. Tests have shown that the tail works really poorly with lower frequency. So unless you notice serious disadvantages (i.e. hot motor or speed controller) don't reduce frequency, maybe even go higher if possible...


The most important points here: Tail adjustment
First check the control direction of the remote control. Right = blue, left = red on the Microbeast or according to the display in StudioX. If the direction is wrong, reverse the control direction in the radio. There is no reverse function on the Microbeast. With "Tail motor" firmware direction is fixed!

The positions for idle, full throttle, motor off and hover throttle are all displayed in microseconds. Default values should fit the Logo 200. Feel free to “play” with the settings again here. If you click on the gear symbol at the bottom, you will be taken to the second page. Motor off position is there: 980µs; from around 1000µs the motor will start to turn. The motor off position is always active as long as the throttle channel for the main motor is below 25% on the radio. As soon as you turn on the main motor, also the tail motor will start to run in hovering position. When in the settings menu, the main motor won't run for safety reasons, so in theory, you may adjust the tail throttle slightly even when on the flying field. The hover position should be set so that the helicopter will not turn around during start and take off. You may have to try something that fits best...

The idle and full throttle positions cannot be tested in the StudioX menu, only adjusted. Idle speed should be selected so that the engine rotates very easily. You can use the Motor off setting to “search” for the position where the engine rotates very slightly, and then adopt it accordingly. Alternatively, you can go out of the menu completely and actually turn on the main motor and then just steer left and right to see how the tail motor behaves and how it is affected by minimum and maximum settings.

Setup by using the device menu As usual, you can setup nearly everything also without StudioX. At Setupmenu item E you can check the control directions of the remote control: red indicates left, blue indicates right. If colors are swapped, reverse stick direction on the radio. Switch on the main motor on the radio, then you can set the hover throtle position at menupoint E. To adjust the throttle tap the tail stick left/right. (ATTENTION!! Rear motor can rotate!)

At Setupmenu item F you can use the stick left/right to set the "Motor off" position while the main motor switch on the radio is off. If you switch on the main motor, you can adjust the idle position by tail stick input.

Other setup steps So now it's almost done. Just check the other setup steps as usual and you’re good to go. The swashplate servos still need to be trimmed. And the control directions from the transmitter must be checked and reversed if necessary. The settings for collective, swash limit and swash throw are already preset for the Logo 200/OMP M2 heli. Of course you can adjust these as needed, when using a different helicopter.

Final steps

Finally, use your radio to set the tail gyro. For the Logo 200/OMP M4 start with 60% of tail gain. Note that unlike the "big" helicopter with conventional tail rotor system, the gain value can be used for all flight modes. Since the tail motor turns independent from the main motor, it can always have the same setting. If tail has not enough stopping power and breaks when you fly around and move collective, it is necessary to increase the gain. The higher the gain, the tighter the tail is held. When the tail only breaks out during pitch pump, check RevoMix setting in StudioX. When gain is too high, the tail will start to overshoot and oscilate. Lower gain immediately in this case. We have also installed a RevoBoost parameter, which additionally accelerates the main motor when you want to steer to the left in order to give the tail an extra push. Left direction is difficult because you can only turn off the motor, but not actively force the tail to the left! Please note the RevoBoost is only active when using the Governor function of MICROBEAST.