当前位置:主页 > 49288.com >

49288.com

汉文翻译英语正版彩图挂牌

发布日期:2019-10-28 10:57   来源:未知   阅读:

  · 850666a.com”我国是文物大国,!单工无线呼叫系统分发射和接收两大部分。根据任务及要求,其工作频率落在30~40MHz频段内,我们选择使用35MHz作为主站发射频率。发射部分采用锁相环式频率合成器技术,MC145152和MC120...

  单工无线呼叫系统分发射和接收两大部分。根据任务及要求,其工作频率落在30~40MHz频段内,我们选择使用35MHz作为主站发射频率。

  发射部分采用锁相环式频率合成器技术, MC145152和MC12022芯片组成锁相环,将载波频率精确锁定在35MHz,正版彩图挂牌,输出载波的稳定度达到4×10-5,准确度达到3×10-5,由变容二极管BB910和集成压控振荡器芯片MC1648实现对载波的调频调制;末级功放选用三极管2SC1970,使其工作在丙类放大状态,提高了放大器的效率,输出功率达到设计要求。

  接收部分以超大规模AM/FM立体声收音集成芯片CXA1238S为主体,灵敏度、镜像抑制、信噪比等各项性能指标均达到设计要求;音频功率放大器采用集成芯片LM386,电压放大倍数最大为200。采用PT2262/2272编码/解码电路实现了数据传输业务以及对台号的选择等功能;音频输入和数据输入可自动转换;AT89S52作为整个系统的控制部分,程序设计采用C语言在KEIL51的编译器上编程实现;显示采用16×02点阵型液晶显示。经测试,整机功能齐全,各项性能指标符合系统要求,接收波形稳定,无明显失真。

  既然都是自动翻译,那你们谁给出好的自动翻译的网站,我给谁最佳吧展开我来答

  可选中1个或多个下面的关键词,搜索相关资料。也可直接点“搜索资料”搜索整个问题。

  The simplex wireless ringing system divides launches and receives two major parts. According to the duty and the request, its operating frequency falls in the 30~40MHz frequency band, we choose use 35MHz to take the master station transmitting frequency. the launch part uses the phase-lock concentric type frequency synthesizer technology, MC145152 and the MC12022 chip composition phase-locked loop, locks precisely the carrier frequency in 35MHz, the outgoing carrier stability achieves 4×10-5, the accuracy achieves 3×10-5, controls oscillator chip MC1648 by varactor BB910 and the integrated pressure to realize to the carrier frequency modulation modulation; The last stage power amplifier selects triode 2SC1970, causes its work in the third kind of enlargement condition, raised amplifiers efficiency, the output has achieved the design requirements. the receiving unit take ultra large-scale AM/FM stereo sound reception integration chip CXA1238S as the main body, the sensitivity, the mirror image suppresses, the signal-to-noise ratio and so on each performance index to achieve the design requirements; The audio power amplifier uses integrated chip LM386, the voltage amplification factor is 200 most greatly. Used the PT2262/2272 code/demoding circuit to realize functions and so on data transmission service as well as to Taiwan choice; The audio frequency input and the data feeds may the automaticswitching; AT89S52 takes overall systems control section, the programming uses the C language to program on the KEIL51 compiler realizes; The demonstration uses 16×02 the lattice liquid crystal display. After the test, the complete machine function is complete, each performance index meets the system requirement, the receive waveshape stabilization, distorts not obviously.

  Receiving part with large scale of AM/FM stereo radio CXA1238S integrated chips, sensitivity, mirror, signal-to-noise ratio etc. Various performance indicators are to meet the design requirements, Audio power amplifier LM386 adopts integrated chips, voltage magnifacation maximum 200. Using PT2262/2272 encoding/decoding circuit realized data transmission and the choice of functions, Input audio and data input can be automatically convert, As the whole system of AT89S52 control section, program design using C language in the KEIL51 compiler programming, Display by 16 points (02 formation LCD display. The test, the function is well-found, various performance indicators with system requirements, the stable, no obvious receiving waveform distortion.

  Receive part of ultra-large-scale AM / FM stereo radio IC CXA1238S as the main body, sensitivity, image rejection, signal to noise ratio and other performance indicators to meet the design requirements; integrated audio power amplifier chip LM386, voltage up to 200 magnification. Using PT2262/2272 encoding / decoding the data transmission circuit as well as its choice of Taiwan; and audio input and data input can be automatically converted; AT89S52 control the entire system as a part of program design using C language compiler in the KEIL51 Programming; show that the use of 16 × 02 LCD. After testing, a full-featured machine, the performance indicators in line with the system requirements, waveform receiver stability, no obvious distortion.

Power by DedeCms