This crude radio transmitter uses a 100Mhz
crystal oscillator to transmit music in a form of Nokia ringtones (RTTTL
sheets).
The hardware is based around an AVR ATtiny 2313
microcontroller. The chip unfortunately, doesn't include USB
functionality,
so the V-USB
library has to be used. This transforms the radio to a USB device capable of receiving USB commands.
Qt5 Graphical User Interface for RTTTL playing in its natural habitat.