| 摘要 |
A frequency-matched signal device for persons with impaired hearing, including an activating member (1,2,3), a signal generator (4) activated thereby for producing an electrical signal with a fundamental frequency which is within the range of audibility of a person having a normal sense of hearing, and an amplifier (10) having a loudspeaker (6) connected after it for amplifying the signal into an acoustic signal. A first device (P1) permits an optional setting of the fundamental frequency of the signal generator; a second device (P3, R1; 13,14,15) permits an optional setting of the signal generator so that it will deliver at least one additional electrical signal of at least one second frequency which is optionally adjustable and related to the fundamental frequency. The additional second signal or signals, respectively, is (are) amplified in the amplifier and an alternator (8) which is connected to the signal generator causes the electrical output signal of the signal generator to alternate between said frequencies at a predetermined slow rate. |
