| 摘要 |
PURPOSE:To allow binary transmission of the power source, voice and data between the main device and the terminal economically by two-line non-polarity by sending at a constant interval bipolar pulses to which positive and negative pulses are connected to the inside of the two-line type transmission line which connects between the main device and the terminal, and by inserting data bit pulses with the same waveforms between those pulse trains. CONSTITUTION:When unipolar pulse trains to which data bit pulses are inserted between pulse trains with a constant interval from a CPU are added to an input terminal 17b in a terminal 3, the unipolar pulse trains are outputted as bipolar pulses whole positive and negative poles are connected on the secondary side of a pulse transformer 19b. The bipolar pulse trains, which are transmitted to a main device 1 through a transmission line 2, pass through a pulse transformer 19a and enter a bipolar pulse receiving side circuit 24a after entering a high-pass filter 20a and removing voice band frequency components. When the output of the pulse transformer 19a enters the bipolar pulse receiving side circuit 24a, the output is rectified by a diode 21a for both waves, and the waveform is shaped by a waveform shaping circuit 22a. Then, it is restored to the unipolar pulse train and outputted. |
