这里介绍一种专利产品(专利申请号:95223366.5)FJ—Ⅱ型电话总机插转器,它可以在资金投入较少的情况下,实现一条外线转接多部分机,并且分别提供一组内线、外线同时通话,互不干扰。该机的功能相当于一部“小总机”,外线转接采用一个分线器。一般情况,可接驳10～30门分机用户。 现将其功能及基本电路介绍如下。 整机电路由六部分组成(见图)。 1.电源电路:4路电压输出,分别由IC7824、IC7812、ICLM317及50VAC供给整机电路。采用IC7824做稳压输出供给通话电路,滤除了不必要的杂音,使通话清晰度高。 2.外线显示电路:当使用外线打电话或接电话时,L1、L2外线接线端电压下降到6V左右,此时光电耦合器 Here to introduce a patented product (patent application number: 95223366.5) FJ-Ⅱ-type telephone switchboard interposer, which can be less invested in the case, to achieve an external transfer multi-part machine, and provide a group of internal, Outside calls at the same time, without disturbing each other. The function of the machine is equivalent to a “small switchboard”, outside the switch using a splitter. In general, it can be connected to 10 ~ 30 extension users. Now its function and basic circuit are as follows. The whole circuit consists of six parts (see figure). 1. Power circuit: 4 voltage output, respectively, by the IC7824, IC7812, ICLM317 and 50VAC supply circuit. Adopt IC7824 to make steady voltage and export and supply and call the circuit, filter out unnecessary noise, make the call clear and high. 2. Outside the display circuit: When using an outside call or answer the phone, L1, L2 outside the terminal voltage dropped to about 6V, this time optocouplers