One of the many special services available to users of "Strowger" Private Automatic Telephones, 'Loud Speaking' enables the executive to communicate with members of his staff without using a telephone handset, thus leaving his hands free to write or to refer to files, wall charts, etc.

Loud-Speaking Facilities

Service is effected by means of a loudspeaker and transmitter, valve amplifier, operating key and lamp, watch-type receiver and dial - the whole assembled in a handsome desk cabinet.

The instrument is ready for use upon the depression of the operating key, which also illuminates the lamp to remind its user that the instrument is 'alive'. Depression of this key is all that is required to reply to an incoming call, but to initiate an outgoing call it is followed by dialling the number of the required individual.

When a call is made from one Loudspeaker to another it is desirable that the Caller should use his watch-type receiver. Incoming calls can be kept secret from other persons in the room by the lifting of this receiver which automatically cuts-out the loud-speaker.

The quality of speech transmission and reproduction is excellent and the volume may be controlled by means of the adjustment screw provided.

With Key-Calling and Conference Facilities.

Where desired 'Loud-Speaking' Service may be supplied with Key-Calling and Conference facilities for ten to twenty lines and in this case the cabinet is fitted with ten one-way or ten two-way keys respectively. 'Key-Calling' enables the user, merely by operating a key and without dialling, to gain access to the line of any one of ten or twenty principal officers, whether or not the required line is engaged at the time.

With 'Conference Key-Calling' he can depress a number of keys and the same number of persons can hear and talk to him simultaneously. In fact, he can hold a conference without leaving his desk. He may withdraw from the conference to dial and communicate with any other line whilst still leaving the conferees connected together. He may also disconnect any of the conference lines by restoring the appropriate keys. The conference is limited to a maximum of ten persons, but any predetermined ten of a total of twenty may be selected.


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Last revised: October 06, 2012