例一京华JW—86放音机开发短波收音功能该放音机采用了ZAG665F立体声集成电路,电路包括双通道前置放大、双通道音频功率放大、电子直流音量控制、直流电机稳速功能,并且不用输入、输出耦合电容,美中不足的是仅能磁带放音而不能收音。经实践,可直接利用双前置放大的微电流偏置检波,增加二个元件,就把单纯的磁带放音机开发出短波收音功能。 Example Jinghua JW-86 radio development of short-wave radio function The player uses a ZAG665F stereo integrated circuits, including dual-channel preamplifier, dual channel audio power amplifier, electronic DC volume control, DC motor speed function, and Do not have input and output coupling capacitor, fly in the ointment is the tape can only play and can not be tuned. Practices, the direct use of dual pre-amplification of the micro-current bias detection, an increase of two components, put a simple tape player to develop short-wave radio function.