| 摘要 |
Measuring arrangement in the shape of a battery-operated handset which is connected to the wire pair of a noise-affected cable and contains the series connection of an evaluation filter in the form of an adjustable equaliser, an amplitude discriminator, a time discriminator and a pulse forming stage in which the full bit-width output pulses of the time discriminator are transformed into half bit-width pulses and the latter are transmitted to a display device. A monoflop with an LED connected downstream can be used as a display, the length of the monoflop time constant being such that the LED is visibly illuminated. The clock generation is carried out independently of the actual PCM system by means of a free-running oscillator, and the transmission of PCM signals is not required. <IMAGE>
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