| 摘要 |
Based on a method in which, when an electro-acoustic transducer is present which is poorly suited to low-frequency transmission, sounds at these frequencies can nevertheless be rendered audible to a listener by generating high harmonics from a signal of this type and then converting them, a telephone subscriber station is proposed which comprises an electro-acoustic transducer (22) for generating signal tones, these signal tones being received at the station input as at least virtually sinusoidal electric signals. The station comprises, for example, conversion means (20) in the handset or receiver with the aid of which high harmonics are generated on the basis of the received sinusoidal signalling tone, for example by amplitude distortion, in particular by forming a square-wave pulse train. The signalling signal thus produced is then fed to the electro-acoustic transducer (22). <IMAGE>
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