Radiolink R7FG 7 Channel 2.4G Gyro RC Receiver Instruction Manual

1. Introduction

The Radiolink R7FG is a high-performance 7-channel 2.4GHz receiver designed for RC cars and boats. It features an integrated gyroscope for enhanced stability, real-time voltage telemetry, and a long control range of over 600 meters. This receiver supports both normal and gyro working modes, offering flexibility for various RC applications. Its anti-reverse plug-in design ensures durability, and FHSS spread spectrum technology provides stable signal transmission.

Figure 1: Radiolink R7FG Receiver with Voltage Telemetry Cable

Key Features:

• 7 Channels: Provides ample control options for various RC models.
• Two-Way Telemetry: Real-time feedback on signal strength and battery voltage.
• Integrated Gyro: Enhances vehicle stability and prevents skidding.
• Anti-Reverse Plug-in Design: Protects the receiver from damage due to incorrect power connection.
• FHSS Signal Spread Spectrum: Ensures stable and interference-free communication.
• Long Control Range: Achieves over 600 meters on the ground.
• PPM & SBUS Output: Flexible signal output options for different setups.

Figure 2: R7FG Key Features Overview

2. Setup and Installation

2.1 Component Identification

Figure 3: R7FG Receiver Pinout and Features

Familiarize yourself with the receiver's ports and buttons:

• VCC/GND: Power input.
• CH1 (Steer), CH2 (Throttle), CH3-6 (Auxiliary): PWM output channels.
• CH7 (PPM/S-BUS Signal): Selectable PPM or SBUS output.
• Telemetry Port (2Pin): For external voltage telemetry connection.
• Bind Button: Used for pairing with the transmitter and changing modes.
• Antenna: Dual antennas for improved signal reception.
• Gyro and Signal LED: Indicates receiver status and gyro mode.

2.2 Binding with Transmitter

The R7FG receiver is compatible with Radiolink transmitters such as RC6GS, RC4GS, RC4G, RC3S, and T8FB.

1. Place your transmitter and the R7FG receiver close to each other, ideally within 50 cm.
2. Turn on your Radiolink transmitter.
3. Power on the R7FG receiver.
4. Locate the black bind button on the R7FG receiver. Press and hold it for 2 seconds, then release.
5. The receiver's LED light will begin to flash. After approximately 8 flashes, if the binding is successful, the receiver signal LED will remain steadily on.
6. Ensure the receiver's antennas are kept as straight as possible and away from metal parts to maximize effective range.

Figure 4: R7FG Bind Button Location

2.3 Wiring and Connections

The R7FG features an anti-reverse plug-in design, meaning the receiver will not be damaged even if the power cable is connected with incorrect polarity. It supports a wide voltage range of 4-10V, allowing for high-voltage servo compatibility.

Figure 5: Anti-Polarity Connection Protection

Voltage Telemetry Connection:

To utilize the real-time voltage telemetry feature, connect the provided voltage telemetry cable to the 2-pin Telemetry Port on the R7FG receiver and to your vehicle's battery (e.g., via an ESC with a balance lead or directly to the main battery terminals if applicable). The telemetry port does NOT support power supply to the receiver.

Figure 6: Vehicle Voltage Telemetry Connection Diagram

For compatible transmitters like the RC4GS or RC6GS, the voltage information will be displayed on the transmitter's main interface. Note that older transmitters like RC3S/RC4G may not display telemetry if they lack a USB port for firmware updates.

Figure 7: Transmitter Display with Voltage Telemetry

3. Operating Modes

3.1 Normal Mode vs. Gyro Mode

The R7FG receiver supports two main operating modes: Normal Mode and Gyro Mode. The integrated gyroscope helps maintain the vehicle's direction and prevents skidding, especially during aggressive maneuvers.

Figure 8: Visualizing Gyro Effect on Vehicle Stability

Activating/Deactivating Gyro:

1. To activate the gyroscope, short press the bind button three times (each press less than 1 second).
2. The red LED light on the receiver will flash three times, then alternate between on and off, indicating that the gyroscope is activated.
3. To deactivate the gyroscope, repeat the same process (three short presses).

Gyro Phase Correction:

Once the gyroscope is activated, it's important to verify its correction direction. This ensures the gyro assists in the correct manner for steering.

1. With the gyroscope activated, gently move your RC vehicle forward.
2. Observe how the gyroscope corrects the wheels when you rotate the car body. For example, if you turn the car body to the left, the wheels should correct to the right. If you turn the car body to the right, the wheels should correct to the left.
3. If the wheel correction is reversed (e.g., turning the car body left causes the wheels to correct left), press the bind button twice (each press less than 1 second).
4. The red LED light will flash twice, indicating that the gyroscope phase correction is complete.

Figure 9: LED Indicators for Normal (Green) and Gyro (Red) Modes

3.2 PPM & SBUS Output Cutover

The R7FG receiver supports 1-6 channel PWM output and can output either PPM or SBUS on the 7th channel. The factory default setting for the 7th channel is PPM output.

1. To switch the 7th channel output between PPM and SBUS, short press the bind button once (within one second).
2. The green LED light will flash once to confirm the button press is registered.
3. When the blue LED light is on, it indicates that the receiver is in SBUS output mode.

4. Specifications

Figure 10: R7FG Technical Parameters

5. Maintenance

Proper maintenance ensures the longevity and optimal performance of your R7FG receiver.

• Keep Clean: Regularly clean the receiver from dust, dirt, and moisture using a soft, dry cloth. Avoid using solvents or harsh chemicals.
• Antenna Care: Ensure the antennas are not bent, cut, or damaged. Keep them as straight as possible and away from carbon fiber or metal parts of your model to maintain signal integrity.
• Connection Check: Periodically inspect all wiring and connections for signs of wear, corrosion, or looseness. Secure any loose connections.
• Storage: When not in use, store the receiver in a dry, cool place, away from direct sunlight and extreme temperatures.
• Avoid Physical Shock: Protect the receiver from impacts and vibrations, which can damage internal components.

6. Troubleshooting

• No Signal/Loss of Control:
  • Ensure the receiver is correctly bound to the transmitter. Re-bind if necessary.
  • Check all power connections to the receiver and ensure adequate voltage (4-10V).
  • Verify that the transmitter batteries are charged.
  • Inspect antennas for damage and ensure they are positioned correctly and not obstructed by metal.
  • Move away from potential sources of 2.4GHz interference (e.g., Wi-Fi routers, other RC systems).
• Gyro Not Working/Incorrectly:
  • Ensure the gyro is activated by pressing the bind button three times (red LED flashes three times, then alternates).
  • Perform gyro phase correction as described in Section 3.1 if the steering correction is reversed.
  • Check for any mechanical binding in the steering linkage that might prevent proper correction.
• Telemetry Data Not Displaying:
  • Confirm the voltage telemetry cable is securely connected to both the receiver's telemetry port and the vehicle's battery.
  • Ensure your transmitter model (e.g., RC6GS, RC4GS) supports telemetry display and has the latest firmware. Older models like RC3S/RC4G may not display telemetry data.
• PPM/SBUS Output Issues:
  • Verify the 7th channel output mode (PPM or SBUS) is correctly set by short pressing the bind button once. The blue LED indicates SBUS mode.
  • Ensure your flight controller or other device is configured to receive the selected signal type.

7. User Tips

• Antenna Placement: For optimal range and signal quality, ensure the two receiver antennas are placed at a 90-degree angle to each other. Avoid coiling or shortening them.
• Firmware Updates: If your transmitter supports firmware updates via a USB port, regularly check the Radiolink website for the latest firmware to ensure compatibility and access to new features, especially for telemetry display.
• Power Source: While the R7FG supports a wide voltage range, always ensure your power source (e.g., ESC's BEC or separate battery) provides stable and clean power within the specified 4-10V DC range.
• Gyro Sensitivity: Experiment with the gyro sensitivity settings on your compatible transmitter to find the optimal balance for stability and responsiveness for your specific vehicle and driving style.

8. Warranty and Support

Radiolink products are manufactured to high-quality standards. For warranty information, technical support, or service inquiries, please refer to the official Radiolink website or contact your authorized dealer. Keep your proof of purchase for any warranty claims.