Each channel has a channel signal switch, high-performance microphone input amplifier circuit.

各通道设有通道信号切换开关，话筒输入设置高性能放大电路。

youdao

The lie detector includes host computer, testing screen, audio and video instrument, answering button keys, answering microphone, brain wave electrodes and pre-amplifier.

测谎仪包括计算机主机，受试屏幕与音响的设备，应答按钮，应答麦克风，及脑波电极与前置放大器。

youdao