Enciphers aggregate (200Baud) output from Telex Over Radio (TOR) MUX equipment. TOR equipments are also known as "EDC", Error Detection & Correction and "ARQ" Automatic Request Repetition.
ARQ rigs employed by the UK military used stepped auto transmitters (Creed 6S6M) so several users could feed one ARQ rack, with the whole lot made secure with the BID620. Most of the time it was just two 50 baud channels, 192 baud aggregate output. But it was possible to split the 50 baud channels into four 50 baud channels that were stepped alternately.
If anyone can provide more info, please contact: Jerry.Proc@sympatico.ca
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