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许多家庭都有收录机。本文介绍的是一种把收录机改装成具有自动录音功能的留言装置。当主人外出时,可把它与门铃接通,并利用它记录下来客的留言。 1:电路原理 该电路如图所示: 当主人离开时,可将电源开关S置于“通”的位置,再按下收录机的录音按键,此时收录机虽接有交流电源,但继电器K未得电,其常开触点K1断开了收录机
Many families have tape recorders. This article describes a tape recorders converted into a voice recorder with automatic recording device. When the owner goes out, it can be connected with the doorbell, and use it to record guest messages. 1: Circuit Principle The circuit shown in the figure: When the owner left, the power switch S can be placed in the “on” position, and then press the tape recorder button, then tape recorder connected to the AC power supply, but the relay K Power, the normally open contact K1 disconnect the tape recorder