A: The operating voltage range of R4FGM V1.0-V2.1 is from 3V to 6V, while the operating voltage range of R4FGM V2.2 is from 3V to 10V which supports high voltage servo.

A:R4FGM is compatible with RadioLink RC8X/RC6GS V3/ RC4GS V3/RC6GS V2/RC4GS V2/RC6GS/RC4GS/T8FB/T8S.

A: Both Red and Green LEDs on mean Gyro Mode while only green LED means Gyro off.

A：

Check the GYRO setting in the menu. Make sure the MIX function is ON and the GYRO sensitivity is well set (not the minimum). When the GYRO Rate value is bigger, the sensitivity is higher while it’s lower if the Rate is smaller.

The GYRO sensitivity can be adjusted by rotating the VR knob (Ch3) or by pressing Dec (-)/Inc (+) buttons below the screen. It depends on whether the Mode you set in the GYRO menu is VR or STD.

A：

① Put the transmitter and the receiver close to each other (about 50 centimeters) and power both on.
② Switch on the transmitter and the GREEN LED on, R4FGM will start flashing slowly.

③ There is a black binding button (ID SET) on the side of the receiver. Press the button for more than 1 second and release, the GREEN LED will flash quickly, meaning the binding process is ongoing.

④ When the GREEN LED stops flashing and is always on, binding is complete and there will be a signal tower shown on top of the LCD screen of the transmitter. If not succeed, the green LED will keep flashing slowly to notify, and repeat the above steps.

Note: If bound to transmitters without a screen like T8S or T8FB, the always-on LED means the binding is completed.

A: The slow flashing LED means binding doesn’t succeed or the signal gets lost after binding completes.

A: Yes. R4FGM V2.1 and R8FG with a factory date of 2023/4/26 and later support 3ms and 4ms digital servo speed.

If you want 3ms or 4ms digital servo speed, please update the firmware of RC8X to V1.1.5 or above, and then select FHSS V2 protocol to display this option. Servo speed can be selected from 14ms, 4ms, and 3ms. The factory default servo speed is 14ms (analog servo speed), 4ms, and 3ms (digital servo speed).

When switching the servo speed, the green LED light of the receiver will flash twice, which means that the switching of the servo speed is successful; if the green LED of the receiver does not flash when switching the servo speed of the servo, it means that the switching of the servo speed of the servo is unsuccessful or the current receiver does not support digital servos.

A: The differences are as follows:

1.When R4FGM is used with RC8X, the supported servo response speeds are different.

R4FGM V2.1 and R4FGM with a factory date of 2023/4/26 or later support 3ms or 4ms digital servo response speed. When using it with RC8X, it supports 3ms or 4ms response speed. Other versions of R4FGM can be used with digital servos, but only support 14ms analog servos response speed.

2. The working voltage is different.

The working voltage of the R4FGM V2.2 version is 3-10V. The working voltage of the previous versions of R4FGM is 3-6V. You can check the supported working voltage from the stickers of R4FGM.