INTERCOMMUNICATION TELEPHONES WITHOUT INDUCTION COIL ELECTRO-MAGNETIC AUTO-RESET TYPE
These instruments are equipped with a combined line selector and ringing key in the a push button, which, when pressed, rings and selects the number required in ration. The buttons are held down during an outward conversation by an auto-vice, which restores the key to the normal position immediately the handset has been replaced on the cradle after a conversation has ceased. Before an outward call is made, it is necessary to remove the handset from the cradle. The button of any one line only be pressed when making an outward call; all incoming calls are answered by removing the handset from the cradle. Designation strips are fitted at the side row of buttons.
All working parts are mounted on a strong steel frame with machine screws and fixed on a wood base, with a black stove-enamelled pressed steel cover overall. All instruments are to the same dimensions, irrespective of the number of lines, and are so arranged all capacity instruments can be extended on site by units of 5 lines, up to their capacity of 21 lines. Spare parts are obtainable for making extensions.
These instruments are suitable for working in conjunction with the Sterling 'Primax'.
Wall type telephone, comprising automatic cradle switch, 25 ohm buzzer, impedance coil, and latest pattern black Bakelite handset without battery key in handle, fitted with a superior quality electro-magnetic receiver and improved type inset transmitter, which can be easily removed.
Dimensions, 10 x 9 x 7 ins.
Note: All these telephones have one more lines than buttons. The home button is used to call the extra station as it would be effectively redundant. So a 5 line telephone can have 6 lines working. The 6th line on telephone number 4 would be button 4.
Last revised: September 23, 2022