RTTY uses a form of transmission known as frequency shift keying. ... In turn these are represented on the radio signal by a shift between two frequencies, one frequency signifying a mark or high voltage and another frequency representing a space of a low voltage.

How do I decode RTTY?

To decode RTTY signals you'll need a shortwave receiver with a BFO (Beat Frequency Oscillator), a way to pipe your radio's audio into your computer's sound card, and decoding software. There are several RTTY software packages out there, free, and my favorite is MMTTY.

Is RTTY a Morse code?

On the 20 metre ham radio band, RTTY activity can be found at the top end of the Morse or CW section of the band between frequencies of 14.080 and 14.099 MHz.