Radiomaster R88 Receiver User Manual

Product Specifications

Channels: 8

Frequency Range: 2400-2483.5 MHz

Power Input Range: 4.5-8.4V

Signal Format: D8/D16v1/SFHSS

Output Format: PWM

Support Return: Supports RSSI return

Range: More than 1km

Antenna Length: 15 cm

Size: 40*26*16 mm

Weight: 11g

Receiver Pinout Diagram

Bind Method

1. Turn on your transmitter and select the desired protocol.
2. Enter bind mode on the receiver: Press and hold the bind button while powering on the receiver. The receiver will cycle between D8, D16, and S-FHSS protocols.
   • Three single flashes indicate D8 protocol.
   • Three double flashes indicate D16 protocol.
   • Three triple flashes indicate S-FHSS protocol.
3. When the flash pattern matches the transmitter protocol, press the bind button on the transmitter. The receiver's light will flash rapidly and then return to solid.
4. Cycle the power to the receiver after binding is complete.

Fail-safe Protection

1. Press the BIND button once within 10 seconds of the receiver being powered on. The receiver will save all current channel values from the remote control as the fail-safe value.
2. After 10 seconds of the receiver being powered on, the BIND button function will be disabled. This prevents accidental changes to the fail-safe settings when preparing the model for flight.

RSSI Output

This receiver provides 8 PWM channels plus 9 SBUS channels (8 control channels + 1 RSSI channel). The 9th channel outputs the signal strength RSSI value. This value can be read by flight controllers and sent to an On-Screen Display (OSD) to show signal strength in the FPV video feed.

Frequency Tuning

Important Note: D8 and D16 compatible receivers require frequency fine-tuning before flight to eliminate frequency errors between the transmitter and receiver, ensuring optimal remote control range and stability.

Follow these steps:

1. Gradually lower the RF Freq. fine tune value until the receiver loses signal. Record this value (TUNE_MIN, typically negative).
2. Gradually increase the RF Freq. fine tune value until the receiver loses signal again. Record this value (TUNE_MAX, typically positive).
3. Calculate the median value using the formula: (TUNE_MIN + TUNE_MAX) / 2 = TUNE_MEDIAN.
4. Set the RF Freq. fine tune parameter to the calculated median value.

Example: If the connection is lost at -73 and +35, the median value is -19.

Once the fine-tuning value is determined, it can be used for all models utilizing the same protocol.

For more information, visit: multi-module.org

Transmitter Setup Menu Screenshot