Protecting the Telephone Operator 



How the loud-speaking telephone elimi- 

 nates danger from high-tension currents 



Th' iipp.ir^itiis 1' prcnlucts the exact tones of the sp. ,iki i \ i u lut v, tli mayulKd volumj 

 and clearness, so that a whisper would be distinctly audible under ordinary conditions 



ELMCTRIC traction and power com- 

 panies usually have their telephone 

 lines on the same poles with high- 

 tension fecHJerandtransmi tier-conductors. 

 Asa result, telcphoneusi'rsnKU'heexpost'd 

 to danger. The high-tension lini's may 

 cross or touch teK-jihone lines, or the in- 

 duced current in the telephone liiii's, due 

 to their being parallel to the high-tension 

 line, may lie sufliciently great to place the 

 telef)hone operator in imminent danger. 



I'"or proN'iding the recpiired protection 

 under the al(o\e conditions, the loud- 

 speaking tele[)Iione has been in\'ented. 

 The person using the telephone does not 

 (ome in aclu.d contact with it. 



The apparatus illuslr.ited rejiroduces 



the voice as spoken into the transmitter 

 with a volume somewhat greater than 

 the s[)eaker's and with perfect clear- 

 ness. If under ordinar\- contlitions a 

 conversation in a rot)m fifteen feet sepiare 

 can he imderstood, the speaker would 

 not raisi' his Noice above the usual 

 l>ilch. In operating the ajiparalus the 

 conversational tone is reproduced 

 with about the same volume and clear- 

 ness. The speaker's natural voice is 

 said to he easier to recognize than in the 

 usual t\pc of ti'lephone. 



Inste.id of lifting the receiver oil the 

 hook, tin- method adopted with the 

 ordinarN' idrphiMU'. the opi'r.ilor presses 

 a lever with his foot to call "cinlr.d." 



70(i 



