本文介绍的电话拨号与计时数字显示器电路集拨号显示和通话计时两种功能于一体,能使用户在拨打电话时显示出所拨打的电话号码,以防止拨错号,同时,在被叫方摘机后能自动开始计时,通话结束后挂号,计时停止并自动保持约1分钟供用户观察。该电路结构简单,新颖实用,而且加装时无需改变话机内部结构,只需将其与话机并接即可,安装甚为方便。 This article describes the dial-up and time-dialing digital display circuit set dial-up display and call timing two functions in one, allowing users to dial the phone number displayed when dialed to prevent dialing the wrong number, at the same time, the called party picks up After the timer can start automatically, after the call is registered, stop timing and automatically maintain about 1 minute for the user to observe. The circuit structure is simple, innovative and practical, and installation without changing the internal structure of the phone, just with the phone can be connected, the installation is very convenient.