Mondial House: ITMCs
Mondial ITMCs
The ITMCs were responsible for testing, aligning and maintaining all of the 12,840 circuits of the ISCs.





Scan: Mondial ITMC - a page from the BTI brochure (1984).
| EXIT | Switch Tour | Next |
| Mondial ITMCs | CPIs | Thames ITMCs |
Mondial ITMCs
Mondial
ITMCs
Mondial ITMCs were the International Transmission Maintenance Centres which were located on the first floor.

Hundreds of Jackfields
The modern layout of jack panels had the standard fuse blocks, mounted horizontally along the top row.

Photo: ITMC © Light Straw October 2001.
The wiring looms show the thousands of connections
Salvaged for parts, the wiring looms are clearly visible.

Photo: ITMC © Light Straw October 2001.
The Raised Floor
Trashed - The supports for the raised floor tiles show the simple but effective design.

Photo: ITMC © Light Straw October 2001.
A Mondial ITMC console
One of the Mondial ITMC consoles. No computer screens, (except a small VDU display *) as levers, buttons, knobs, switches, meters and lamps were adequate.

Circuits were tested and aligned, faults were located and cleared, routine tests performed, all from these 'filing cabinet' type workstations.


Photo: ITMC console © Light Straw Oct 2001.
CPIs

Call Progress Indicators

To monitor the progress of calls through the exchange equipment, circuits could be connected via the test access system to one of six CPIs which displayed the input/output signals via filament lamps held in multi-digit indicators. Each CPI contained up to 500 lamps.

The 6 CPIs were for the following types of signals:
  • AC4 (1 set)
  • AC4 (2nd set)
  • AC10 (1 set)
  • AC10 (2nd set)
  • AC9 AC11
 
* The status of the display panel of each CPI rack was relayed to the test desks via a TV camera mounted overhead on the rack tie bars.

Peter Walker explains... "The display panels were quite large (pixie tubes, I seem to remember), so a camera was put in front of them and the picture relayed to a small VDU on the test desk. You can see this screen on the picture of the Mondial ISC test desk, top right of the left hand panel."

Thames ITMCs

Thames
ITMCs
Thames ITMCs were the International Transmission Maintenance Centres which were located on the first floor.

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