文件名称:e02ch14
介绍说明－－下载内容均来自于网络，请自行研究使用
a 555-based project that can be used as mailbox alarm.
By suitable mounting of the LED and the phototransistor, the circuit
is able to detect when a letter is dropped in your mailbox.
By suitable mounting of the LED and the phototransistor, the circuit
is able to detect when a letter is dropped in your mailbox.
(系统自动生成,下载前可以参看下载内容)
下载文件列表
e02ch14.pdf