本人曾接修了一只“电话精灵”。该装置设计精致巧妙,能防非法接入的用户占线盗打、防串线的分机窃听,所用都是通用、小型元件。线路板面积只有3.5×4cm,很适合电子爱好者自制,特测绘了电原理图如下。其中主要元件型号均未标注,但有一定电子基础的人均可以根据使用场合确定。 图中A、B为接在本装置后的两个合法分机,虚线接入的C假设为在电信局与本装置之间某一点接入的非法并机。防盗打原 I had to pick up a “telephone wizard.” The device is designed exquisite and ingenious, to prevent unauthorized access to users of theft, anti-string extension eavesdropping, are used in general, small components. Circuit board area of ​​only 3.5 × 4cm, it is suitable for electronic hobby self-made, special measuring the electrical schematic is as follows. One of the major component models are not marked, but there is a certain number of electronic basis per person can determine the use of occasions. In the figure, A and B are two valid extensions connected to the device. The dotted line access C is assumed to be an illegal parallel connection at a certain point between the telecommunication bureau and the device. Anti-theft hit the original