SX1278 LoRa 433MHz Ra-02 Wireless Module

The Ra-02 is a long-range wireless transmission module based on SEMTECH’s SX1278 transceiver. It uses LoRa spread-spectrum technology for reliable communication over distances up to 10,000 metres, with strong anti-interference performance, high sensitivity, and low power consumption.

With sensitivity down to -148 dBm and RF output up to +20 dBm (100 mW), it is suited to meter reading, smart-home systems, burglar alarms, remote monitoring, and other long-range wireless projects.

Features

• LoRa spread-spectrum modulation technology
• Constant RF power output up to +20 dBm (100 mW)
• Half-duplex SPI communication
• Supports FSK, GFSK, MSK, GMSK, LoRa and OOK modulation
• Automatic RF signal detection, CAD mode, and high-speed AFC
• Packet engine with CRC support up to 256 bytes
• Compact dual-row stamp-hole package
• Shielded housing
• Spring antenna included

Specifications

• Communication distance: Up to 15 km
• Sensitivity: Down to -148 dBm
• Programmable bit rate: Up to 300 kbps
• RSSI dynamic range: 127 dB
• Wireless frequency: 433 MHz
• Working voltage: 1.8–3.7 V
• Working temperature: -40°C to +80°C

Arduino Uno / Nano Pinout

The module communicates with Arduino through SPI.

Important Voltage Note

Power the module from 3.3 V. Its logic level is also 3.3 V, so a level shifter is recommended when using a 5 V Arduino.

Components Required

• SX1278 / Ra-02 433 MHz module
• Arduino Uno, Nano, Mega, or compatible board
• Jumper wires
• Breadboard (optional)
• Antenna for the LoRa module

Arduino Library Setup

1. Open Arduino IDE.
2. Go to Sketch → Include Library → Manage Libraries.
3. Search for LoRa.
4. Install LoRa by Sandeep Mistry.

LoRa Transmitter Code

#include <SPI.h>
#include <LoRa.h>

void setup() {
  Serial.begin(9600);
  while (!Serial);
  Serial.println("LoRa Sender");
  if (!LoRa.begin(433E6)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }
}

void loop() {
  Serial.println("Sending packet...");
  LoRa.beginPacket();
  LoRa.print("Hello World");
  LoRa.endPacket();
  delay(1000);
}

LoRa Receiver Code

#include <SPI.h>
#include <LoRa.h>

void setup() {
  Serial.begin(9600);
  while (!Serial);
  Serial.println("LoRa Receiver");
  if (!LoRa.begin(433E6)) {
    Serial.println("Starting LoRa failed!");
    while (1);
  }
}

void loop() {
  int packetSize = LoRa.parsePacket();
  if (packetSize) {
    Serial.print("Received packet: ");
    while (LoRa.available()) {
      String received = LoRa.readString();
      Serial.print(received);
    }
    Serial.print(" with RSSI ");
    Serial.println(LoRa.packetRssi());
  }
}

Package Includes

• 1 × SX1278 Ra-02 module