Gamewell fire alarm and police telephone system installed in Liverpool

This paper describes the methods adopted for meeting the following main requirements of a combined fire alarm and police telephone system. Regarding the former, (1) the system to be operated on the closed-circuit principle; (2) the calls, transmitted in code, repeated twice, to be simultaneously and automatically received at the associated district fire station and central fire station; (3) all calls to be received without interference; (4) in the event of a box circuit being broken, the apparatus automatically to set itself for receiving calls over the broken line. Regarding the police telephones: (1) the system to be operated over the same street lines as those used for the fire alarm system, but the latter to be in no way interfered with; (2) facilities to be provided for calling the central police exchange from any telephone box. The system is quite satisfactory, all fire alarm calls being received within 10 seconds.