| 摘要 |
<p>A TELEPHONE FOR A PHYSICALLY HANDICAPPED PERSON A telephone for a physically handicapped person has a transducer which is selected for easy actuation by the handicapped person. The transducer may, for example, be operated orally. When the transducer is first operated, a switch under the control of the transducer causes the telephone line switch to go "off hook" and, after a suitable delay, causes outpulsing of a zero signal to alert the operator. Once contact with the operator is established, the caller who has access to a telephone microphone, asks the operator to place the call and subsequently participates in it. Following the termination of the call, the transducer is operated again to reactuate the line switch and return the telephone set to its "on hook" condition. A similar procedure is followed when a call is received by the handicapped person. However, in this case, since no zero dialling is required, ringing voltage on the line is detected and, while present, zero dialling in response to transducer actuation is prevented.</p> |
