Clones
After Honeywell discontinued production of Sigma hardware several companies produced or announced clone systems. The Telefile T-85, introduced in 1979, was an upward compatible drop in replacement for 32-bit Sigmas. Ilene Industries Data Systems announced the MOD 9000, a Sigma 9 clone which had an incompatible I/O architecture. Realtime Computer Equipment, inc. designed the RCE-9, an upward compatible drop in replacement which could also use IBM peripherals. The Modutest Mod 9 advertised hardware and software compatibility with the Sigma 9.
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