SQ2CPA LoRa APRS Balloon (+WSPR)

Check my parts list here

This firmware is suitable for LoRa based balloon trackers. For now its good for HT-CT62 board that includes ESP32C3+SX1262. It contains many good features like historical location, current flight day detection and even digipeater so you can repeat your messages via balloon via LoRa APRS!

Configuration

All configuration is located in ./src/configuration.h. You don't need to Upload Filesystem Image, all configuration is filled within code, not SPIFFS anymore!

Pinout

• GPIO9 to VCC during flight, GND for programming.
• GPS TX at GPIO0, GPS RX at GPIO1 (I prefer ATGM336H-5N31)
• SI5351 at SCL GPIO19 and SDA GPIO18 (only for WSPR!)

Tips

• Use external BOD 2.8-3V for ESP32 because of broken Internal BOD
• GPIO9 to GND for programming, to VCC during flight (more safety)
• Use 3.3V LDO if voltage >3.5V due to HT-CT62 datasheet (more safety, I don't know what is the real good max. voltage)
• You don't need external I2C pull-up resistors for WSPR

Based on Ricardo CA2RXU LoRa software that is available here.

73, Damian SQ2CPA, Poland