As I understood it, (but I could be wrong), the 'Mediator Suite', - which sounds like a work by Vaughan-Williams, was the name of the furniture in use at Manchester and LATCC.
It usually comprised 2 horizontal radars, with the capability to accommodate 4 sector controllers (2 on each), A Chief Sector Controller (also known as a Crew-Chief or CSC), was in overall charge of the suite, and ATSAs manned the 'wings' or ends of each suite. A 'canopy' provided fittings for the lights, kept the smoke in the vicinity of the ATCOs and tall Chiefs could grab the canopy handles in times of crisis.
Some LATCC suites had positions for military bods too (Pole Hill did, - I think) and the TMA East suite at Manch had the approach controllers sitting next to the SE sector controller.
Each sector had its own suite, Daventry, Clacton, Dover/Lydd etc. If you find one in a museum, you can tell where it came from as the Manchester ones were dark green and the others, from LATCC and CATC were grey.
Sorry to hi-jack the 424 thread, all this should be filed under ATC History really.
Manchester can use Clee Hill and St Annes PRI/SSR data when the EGCC Watchman is U/S, but I believe they have to use 4000' initial altutude to comply with terrain clearance, and 5nm minimum separation instead of 3.
Please feel free to correct any of the above folks if it's wrong. I'll try and finish the EGCC radar thing this weekend.
.