Title : 
The Bell System speakerphone
         
        
            Author : 
Clemency, W. F. ; Romanow, F. F. ; Rose, A. F.
         
        
            Author_Institution : 
Bell Telephone Laboratories, Inc., Murray Hill, N. J.
         
        
        
        
        
            fDate : 
5/1/1957 12:00:00 AM
         
        
        
        
            Abstract : 
The Bell System Speakerphone provides hands-free telephony. It permits the telephone customer to receive over a loudspeaker and to transmit over a microphone located a convenient distance away. The techniques and components employed in the design of the Speakerphone are described. A survey of customer reactions to this type of telephone set indicates that 90 per cent are fairly or entirely satisfied with its performance.
         
        
            Keywords : 
Acoustics; Coils; Couplings; Loudspeakers; Microphones; Speech; Telephone sets;
         
        
        
            Journal_Title : 
American Institute of Electrical Engineers, Part I: Communication and Electronics, Transactions of the
         
        
        
        
        
            DOI : 
10.1109/TCE.1957.6372645