论文部分内容阅读
一、伴音中放集成电路μPC17C的代换有台日立20CT8600DU型的彩色电视机,出现有光栅、有图像、无伴音的故障现象。本机是进口机型,不敢盲目乱动。首先检查伴音通道,发现伴音中放集成电路μPC17C内部电路损坏。该块内部包括伴音前置中放电路、限幅器、伴音鉴频器电路等。由于手头没有此集成电路。询问几家邮购单位也购不到此件。于是设想用分立元件组装来代替此块功能,通过查阅资料,发现可用TBA120S组成的电路来替代此机的伴音中放电路(这种电路曾在某报刊上登
First, the sound put put the integrated circuit μPC17C substitution Taiwan Hitachi 20CT8600DU-type color TV set, there is a grating, an image, no sound fault phenomenon. This machine is imported models, not blindly moving. First check the audio channel and found that the audio amplifier integrated circuit μPC17C internal circuit damage. The block includes the sound front in the discharge circuit, limiter, audio frequency discriminator circuit. Because there is no integrated circuit on hand. Ask a few mail-order units can not buy this piece. So imagine the use of discrete components to replace this block assembly function, access to information and found that the circuit can be made of TBA120S alternative to the sound of this machine in the discharge circuit (this circuit has been published in a newspaper