WTT Communications Ltd. is now the preferred supplier of Professional Engineering design/build electromechanical (relay-based, analog) telephone services for commercial, governmental, institutional and military applications in Canada and abroad. These services are available any time on a "Request for Quotation" (RFQ) basis. Please feel free to contact us, or call us at (416) 536-9252.

Following is a sampling of Special Assemblies designed and fabricated by WTT to meet specific customer requirements:

Generating Station Communications Simulator

Logic-10 telephone sets and a custom-designed electromechanical Key Service Unit provide a small-scale emulation of a larger corporate communication system. The simulators are used for training personnel in three Ontario Hydro coal-fired generating stations.

Fall-back System for Microwave Communications Network

Developed to meet European naval specifications, this unique rack-mounted Special Assembly links a number of military installations together over the PSTN. Its purpose is to provide high-reliability back-up communication links in the event of failure of the (primary) microwave network. Where required, Western also provides direct-access emergency reporting systems over private wire.

Back-up Telephone System in Power-Fail Conditions

Modified Logic-10 telephones and passive ringing switchers provide back-up service for an ambulance dispatch centre. In the event of main system failure or prolonged power outage at the facility, the seven dispatchers and three radio operators can each plug in one of the special sets, allowing each access to a fixed group of the system's 90 lines. The sets provide a visual ringing signal for each line, and a bell common to the set's line group.

Multi-Zone Paging Adaptor

Electromechanical switching components provide interfacing between a Toshiba digital Key System and a three-zone paging facility at a Toronto auto dealership. The Special Assembly enabled the new Toshiba to connect with an existing, leased Seeburg paging system which had previously been accessed by separate, proprietary telephone sets.

Multi-Point "Hollerdown" Termination on Key System

Logic-10 telephone sets, 1A2 key equipment and a custom-designed private line interface allow a Sudbury auto parts dealer to access standard telephone lines and a multi-point parts dealers' hot-line from the same telephone sets. The 4-wire private line serves 50 parts dealers throughout Ontario. When not in use by a telephone in the Sudbury system, the line is monitored on loudspeakers.

Public Transit Maintenance Communications System

A power plant, patch field and 203A Key Telephone Units are the essential components of two "party line" systems used for track-level maintenance communications by the Toronto Transit Commission.


In the process of supporting our generic key customer base, WTT has developed several enhancements for 1A1 and 1A2 Key Systems. Among them are:

  • Hold Recall

    An incoming call placed on hold rings back to the answering position after a timed interval, and marks the line with a distinct visual signal.

  • Handsfree Door Intercom

    Allows a standard door intercom box to originate a call on a key system intercom.

  • Message Waiting

    A multi-button console and the hold button lamps on conventional key sets are used to provide visual message indication to key telephone users who share the services of a message centre.

  • Auto-Answer and Hold

    After a preset interval, unanswered calls to an Order Centre are answered, played a recorded message, then placed on hold by the system. Lines with such calls are then marked with a distinct visual signal.

  • Incoming Call Routing

    Any incoming call on the system is routed to an answering machine, which takes a message unless a user accesses the line during the machine's ring setting.

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