Flexible Arduino-based tracker software for RTTY, LoRa and APRS.
Using #defines in the main file, this can be configured for any combination of RTTY (using NTX2 or MTX2), LoRa (RFM98) and APRS (HX1). Various parameters such as transmit frequency can be adjusted also.
The default configuration is for the HABduino tracker - see http://www.habduino.org/, using RTTY and APRS.