| 摘要 |
<p>A device enabling disabled people to summon assistance in an emergency normally comprises modified telephone appts. On operation of an emergency switch the appts. calls the programmed number until the latter responds, and then transmits a prerecorded message. In order to reassure the caller that the message has been sent and received something more than an indicator light is psychologically desirable. The appts. is therefore fitted with a loudspeaker that plays the transmitted message and the replay or acknowledgement from the receiving station. Message and response may be played at different sound levels.</p> |
