PURPOSE: To surely interrupt an output transistor circuit of a reproducing relay circuit at non-signal, by turning off an output signal of a non-signal detection circuit for two semiconductor elements generating a pulse signal of positive and negative polarity respectively.
CONSTITUTION: A non-signal detection circuit NSD transmits a control signal to a discrimination circuit when no PCM signal is received. A discrimination circuit DC discriminates the polarity of each pulse of the received PCM signal, generates two high level RZ pulse signal corresponding to the polarity of each pulse, receives an output of a low level through the reception of the control signal from the non-signal detection circuit NSD and generates the output of a low level. A reproducing circuit RC' is provided with two semiconductor elements generating the pulse signal of positive and negative polarities, which are turned on with the output pulse signal of the discrimination circuit DC. The semiconductor elements are turned off with the low level output of the discriminating circuit DC.
ARAI MASANORI
NISHIZAKI KOUJI
| JPS5111448A | 1976-01-29 | |||
| JPS55118255A | 1980-09-11 | |||
| JPS4822215A |