MATEK EXPRESSLRS ELRS 2.4GHZ RECEIVER ELRS-R24-S

ELRS-R24-S Specifications

• ESP8285, SX1280/1281IMLTRT
• PA/LNA: AT2401C
• Molex 479480001 SMT antenna
• RF Frequency: 2.4GHz ISM
• Telemetry power: 20dbm
• AT2401C Rx_gain: 12dB
• Receiver protocol: CRSF
• Input voltage: 4~9V DC @ 5V pad
• Power dissipation:  40~45mA(before binding), 60~65mA(binding), 90~95mA(wifi mode)
• PCB size: 21mm x 15mm
• Weight: 1.2g
• Packing: 1x ELRS-R24-S

Firmware

• ExpressLRS MATEK_2400_RX
• Firmware update via UART or WIFI
• ELRS-R24-S:  disable “USE_DIVERSITY” (unchecked) when flashing in ExpressLRS configurator

DOWNLOADS:

• 3D STEP file
  
  FIRMWARE
• Tool:  ESP_NodeMCU-PyFlasher.exe
• No bind phrase
• ELRS_V1.2.0_NoPhrase_ELRS-R24-D.bin
• ELRS_V1.2.0_NoPhrase_ELRS-R24-S.bin
• ELRS_V2.0.0_NoPhrase_ELRS-R24-D.bin
• ELRS_V2.0.0_NoPhrase_ELRS-R24-S.bin

Additional Information.

• “Any ELRS 2.4Ghz receivers can work with any ELRS 2.4Ghz TX Modules, from any manufacturer and even the DIY ones. This is as long as they have the same binding phrase and configuration options (Regulatory Domain, Performance Options, and Extra Data).”
• For more details about ExpressLRS, please check out  ExpressLRS wiki

Wiring with FC

• Receiver RX — FC UART_TX  for Telemetry
• Receiver TX — FC UART_RX  for Control
• Receiver 5V — FC 5V or 4v5
• Receiver G — FC GND
• Receiver protocol: Serial-based receiver – CRSF

Traditional Binding

• Receivers have ExpressLRS FW preloaded without BINDING_PHRASE

1. Power on and off your receiver three times
2. Make sure the LED is doing a quick double blink, which indicates the receiver is in bind mode
3. Use the [BIND] button on the Transmitter Lua script, which sends out a binding pulse
4. The receiver will switch to slow blink once it has received a binding pulse.
5. Power off and power on the receiver again. If the receiver LED switches to solid on from slow blink, it’s bound with your transmitter.

• Important: If the RX firmware has a bound phrase, the RX will never enter binding mode using the above procedure. It must be flashed without a binding phrase to do the traditional binding.

Flashing with ESP_NodeMCU-PyFlasher

1. Connect receiver to USB-TTL module(RX-TX, TX-RX, 5V-5V, G-GND)
2. Connect the USB to the PC while pressing and holding the boot button in.
3. Open ESP_NodeMCU-PyFlasher
4. Select the Serial port of the USB-TTL module,  load firmware,  select “Dual Output(DOUT)”  and “Yes, wipes all data“
5. Click “Flash NodeMCU“
6. After flashing, Power off and power on your receiver, the receiver will enter binding mode(quick double blink).

Flashing with the ELRS configurator

• R24-S,  MATEK_2400_RX target.
• R24-D,  MATEK_2400_RX target for ELRS1.x & 2.x,    MATEK 2400 RX R24D for ELRS3.x or newer

Troubleshooting

• If the receiver can’t be flashed via WIFI or BF pass-through when it comes with preloaded firmware. You may recover it by flashing it via UART.
• Wire the receiver into the USB-TTL adapter, with TX on the receiver connected to the Rx on the USB-TTL, and RX on the receiver connected to the Tx of the USB-TTL. Wire 5V and GND of the USB-TTL to 5V and GND of the Receiver.  Press the boot button while powering the RX on, and release – the LED should now be solid.
• Select the target MATEK_2400_RX and  “UART” for Flashing Method, insert your bind phrase and Firmware Options, and once done, click on Build and Flash.
• For ELRS-R24-D, if update from 2.x to 3.x, Please select target MATEK 2400 RX R24D and click on Force Flash.