AMTOR
AMTOR is a type of telecommunications system that consists of two or more electromechanical teleprinters in different locations that send and receive messages to one another. AMTOR is a specialized form of RTTY protocol. The term is an acronym for Amateur Teleprinting Over Radio and is derived from ITU-R recommendation 476-1 and is known commercially as SITOR (Simplex Telex Over radio) developed primarily for maritime use in the 1970s. AMTOR was developed in 1978 by Peter Martinez, G3PLX with the first contact taking place in September 1978 with G3YYD on the 2m Amateur band. It was developed on home made Motorola 6800 based microcomputers in assembler code. It was used extensively by amateur radio operators in the 80s and 90s but has now fallen out of use as improved PC based data modes are now used.
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