Analysis of information sources in references of the Wikipedia article "Headphones" in English language version.
Upper right image: A New York City central office in the '80s, showing "beehive" as well as early desk type switchboards, and both young women and boy operators [Note image of telephone operator's with head-mounted telephone receivers]
{{cite journal}}: CS1 maint: others (link)The transmitter is placed on an upright rod at his right and the receiver is held constantly at his ear by means of a steel band passed over the head which band serves also as the magnet of the telephone He is therefore always in readiness to receive an order without the necessity of a preliminary call or signal and both his hands are left free to fill the orders. [Also see Figure 180]
Figure 73
Figure 1
Referring to the illustrations on page 251, A is the switchboard, B is the inclined shelf usually employed in upright switchboards and C is the headphone.
For the first week she does nothing but attach her headphone to an experienced operator's position and listen. [pp. 401]
Listening in --. Keep the head phones on the head and at end of every sentence throw up listening key with fingers or thumb of right hand to assure yourself that the other party hears you clearly and answers you
My headphones are of the single pole type wound to the resistance of 3,000 ohms.
Even the flimsiest, cheap headphones routinely boast extremely low bass-response performance—15 or 20Hz—but almost always sound lightweight and bright.
{{cite web}}: CS1 maint: location (link)Even the flimsiest, cheap headphones routinely boast extremely low bass-response performance—15 or 20Hz—but almost always sound lightweight and bright.
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