论文部分内容阅读
有时需要在家庭内部房间之间进行通话,这时可以通过安装一个简易内部对讲机来解决这一问题。该对讲机的电路如图所示,IC(LM 390)是1 W的音频功率放大集成电路,共有14个引脚,是双列直插式结构,在本电路中电压增益可达300 dB,如有纹波信号干扰,可在①脚到地之间接一只10 μF或更大的电容即可消除。R_3、C_4可以增强电路的稳定性。电路中有两个扬声器:一个扬声器和听、讲选择了开关S_1放在主控制室内,另一个扬声器B_2及开关S_2放在需要通话的房间内。平时开关S_1、S_2均搬到“听”的位置。当开关S_1搬到“讲”的位置时,主扬
Sometimes you need to talk between rooms in your home, and you can solve this problem by installing a simple intercom. The walkie-talkie circuit shown in Figure, IC (LM 390) is a 1 W audio power amplifier integrated circuit, a total of 14 pins, dual in-line structure, the voltage gain in this circuit up to 300 dB, such as A ripple signal interference, can be in ① feet to ground between a 10 μF or greater capacitor can be eliminated. R_3, C_4 can enhance the stability of the circuit. There are two speakers in the circuit: a speaker and speaker, speaker S_1 in the main control room, speaker B_2 and switch S_2 in the room to talk to. Usually the switch S_1, S_2 are moved to “listen ” position. When the switch S_1 moved to “talk ” position, the main Yang