七管超外差幅收音机、、.docVIP

七管超外差调幅收音机 摘要 无线通信在现在的生活中尤为重要，我们常用的手机，无线电话还有各种电器的遥控器等，都离不开发射和接收设备。调频与调幅是目前应用最广的两种发送接收方式，随着社会发展调频方式越来越成为现代设备的必要工作方式。 所谓超外差，是指将所要接收的电台在调谐电路里调好以后，经过电路本身的作用，就变成另外一个预先确定好的频率，然后再进行放大和检波。这个固定的频率，是由差频的作用产生的。在超外差式调频接收机的设计过程中，应将其分为高频放大、混频、本振、中放、鉴频、低频放大六个部分。 但是在设计时必须全面考虑，妥善处理一些相互牵制的矛盾，特别要抓住主要矛盾（稳定性、选择性、失真等），才能使得接收机有较好的指标。超外差式接收机能够大大提高接收机的增益、灵敏度和选择性。 关键词：超外差，焊接，调试，调频 Seven tube specialized superheterodyne an am radio Author:Tong wen jing Autor:Bai xiao lei abstract wireless communications in the life now is especially important, we used to use mobile phone, wireless phone there are all kinds of electric remote controls, etc, is inseparable from the sending and receiving equipment. FM and modulation is currently the most widely used two send receiving mode, along with the social development has become a more and more modern equipment FM way the necessary way to work. The so-called specialized superheterodyne, it is to point to will have to receive radio tuned circuit in the adjusted the later, over the role of the circuit itself, they become another a predetermined frequency, and then amplified and detection. The fixed frequency, is by the difference frequency role of generation. In the design of the specialized superheterodyne receivers in FM process, should be classified into the high frequency amplifier, frequency mixing, the vibration, putting, popularly used, low frequency amplifier six parts. But in the design must be fully considered, properly deal with some mutual contain contradiction, special to catch the main contradiction (stability, selectivity, distortion, etc), to make a good index receiver. Specialized superheterodyne receivers can greatly improve the receiver of the gain, sensitive and selective. key words : Specialized superheterodyne, welding, commissioning, FM 目 录 1 实训目的 1 2 工作原理 2 3 实训内容 3 3.1实习器材 3 3.2 元件说明 3 3.3安装顺序 3 3.4收音机的组装 4 3.5收音机的调试 4 3.5.1调幅（AM）部分 4 3.5.2调频（FM）部分 4 4注意事项 6 4.1 焊接的热量和焊接的时间 6 4.2焊接过程的把握 6 5