This project / module tries to model a dual heterodyne radio for VLF (Very Low Frequency) transmissions. These transmissions are well below the frequency range of standard radios, but some fall in the frequency range of audio interfaces.

Examples:
When Mike Oldfield recorded “Tubular Bells”, a test transmission of the nearby VLF transmitter at Rugby was accidentally recorded and made it into the master. The transmitter with call sign GBR operated at 16KHz.
Load the beginning of Tubular Bells into the FlexiSampler and hear the morse code! This works best with a WAV recording directly from CD.

SAQ in Sweden operates at 17.2 KHz. It is a very unique museum transmitter that is usually active twice a year. More information at https://alexander.n.se/en