The MMS took over from the Thyratron in 1977.
This was a 240 channel system with 2 x 8K ferrite memory cores giving a total of 130 cues.
It had one manual playback and 2 rate playbacks which was a good solution.
Library storage was by magnetic tape.
A Standard Pin Patch and also a custom panel for houselights plus lamp mimic was also in the console.
The MMS was believed to have been replaced in the early 1990s by an ETC console.

MMS at National Theatre, Reykjavik
From Alan Luxford Collection
Click thumbnail to enlarge

MMS at National Theatre, Reykjavik
From Alan Luxford Collection
Click thumbnail to enlarge