Beta Release: SSB Firmware for QMX/QMX+ Transceivers

QRP Labs releases a beta version of SSB firmware for its QMX/QMX+ transceivers. This firmware utilizes polar modulation and boasts a rich feature set including audio equalization, microphone AGC, compression, and digital pre-distortion. The release includes comprehensive instructions and testing procedures, along with a microphone test tool and a calibration tool to optimize SSB performance. The article details the underlying polar modulation technique and explains the firmware's features and known issues.