| 摘要 |
PURPOSE:To increase the length of a line to be transmitted and to improve the repetition frequency of a transmission signal, by providing a circuit element including a capacitor mounted externally to a primary winding of a transformer at transmission side, and applying a voltage corresponding to a differentiating waveform of an on/off current to the primary winding so as to attain transmission. CONSTITUTION:Immediately after a driver switch 7 is turned on, a large charging current flows to a capacitor 9, the charging current starts reducing as the charging of the capacitor 9 advances, a potential at a point (b) as shown in Figure changes as shown in Fig. (B), and when turned off, the charge of the capacitor 9 is discharged via a resistor R2 and the potential at the point (b) changes as shown in Fig. (B). That is, a voltage Vi shown in Figure corresponds to the differentiation of the waveform shown in (A), and a voltage comparatively close to a rectangular waveform appears at the secondary circuit of the receiving transformer as shown in Fig. (C). As a result, the permissible length of a transmission cable 3 is increased and the repetition frequency of the transmission signal is improved. |
