teleprinter exchange (Telex)
Telex, Teleprinter Exchange (Telex), is an internationally standardized telegraph service for transmitting teletype characters in the International Telegraph Alphabet No. 2, the IA-2 alphabet, and if certain rules are followed, transmitting differently coded information in 5-bit code.
The teletype service, which was introduced in Germany as early as 1933, requires uninterrupted operational readiness of the connected devices. Terminals are teleprinters that print out the transmitted texts on continuous rolls. The transmission speed is only 50 bit/s, which corresponds to a character speed of 6 2/3 character/s. The character frame consists of 1 start bit, 5 information bits and 1.5 stop bits. The mode of operation for transmission is half- duplex; the bit error rate is `10^-6`.
Additional features: Speed dialing, broadcasting, hinting, subscriber operation classes.