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BELL SYSTEM TECHNICAL JOURNAL 



ments on the handle this additional coupling is often sufficient to cause 

 howling. 



Since with the deskstand a flexible cord forms the only connection 

 between the transmitter and receiver, the user is always able to hold 

 the receiver to his ear and at the same time to speak with his lips 

 directly in front of the transmitter. The handset handle, however, 

 defmitely establishes the distance between the two instruments. If it 



1.5 2.0 2.5 



TALKING DISTANCE IN INCHES 



Fig. 2 — Loss in transmitter output with distance from the mouthpiece. 



is too short, many users are unable to hold the receiver on the ear when 

 the transmitter is in front of the lips. This difficulty has often been 

 avoided by making the handle long enough to accommodate any user. 

 If this is carried to an extreme, the distance between the transmitter 

 and the lips is greater than necessary, and introduces an avoidable 

 transmission loss for the majority of users. As may be seen from the 

 curve shown in Fig. 2, this loss may be quite large and warrants every 

 effort to minimize it. 



If the convenience of the handset is to be fully realized, it is impor- 

 tant that the handle be shaped to fit comfortably in the hand and that 

 the complete handset be sufficiently light to a\ oid fatigue on the part 

 of the user. These structural limitations add a further problem in 

 design. 



