Radioteletype

Radioteletype (RTTY) is a telecommunications system consiting of two teleprinters linked by a radio link.

RTTY used a variety of different modulation methods, of which frequency shift keying was the most common. The coding used was the 5-bit Baudot code, also known as IA2?, which was used asychronously with start and stop bits.

RTTY was not fast by modern standards; a typical [baud rate]? for RTTY operation was 75 baud.