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KDB178919变更许可的政策，定义了3种变更许可类型Class I, Class II, Class III 。
Class I Permissive Change:产品的改变不会对EMC产生影响,如外观颜色的改变,处理方法：不用提交资料给FCC,在原报告上增加相关的描述即可Class II Permissive Change：产品的改变会对EMC产生影响,如重新layout,增减个别元器件等处理方式：测试辐射和输出功率,功率变化不能超过+/-0.5dBm(传导方式）,或是+/-3dBm（辐射方式）否则需作为新的产品申请新的IDClass III permissive change仅适用与软件无线电（SDR）设备变更中涉及到主频，稳态电路(时钟信号、数据速率)，倍频电路，调制电路，最大功率和磁场强度等级等硬件指标的，通常需要实验室判定，作为一个新认证申请FCC ID 。
一般改型机变更的类别：1. 天线的变更2. PCB 和硬件的变更3. 外壳的变更4. 软件的变更5. 综合性变更Note：1.对于一个改型机的变更，必须考虑所有的变更来确定所需的变更许可类型。
例如,软件变更曾加额外的频率是可以被允许的变更许可。
但是如果新频带的功率增加，则根据2.1043要求需要作为新产品申请新的FCC ID;2.当一个Class II 变更，申请EMC或 RF exposure (RFx)认证，必需有EMC测试报告或RFx评估，无论EMC或RFx数据有明显的降低。
3.关于助听器(HAC)的变更许可的政策有一个单独的标准文件：KDB 285076。
1).天线变更更换等效的天线归类于Class II类改型，更换成小增益的天线可评估归类于Class I 类变更。
a.等效类型天线：i.当一个Part15认证申请包含天线的清单和照片，天线的清单需要包含在申请中。
天线的类型、增益、型号、制造商要求被列出；ii.替换的等效天线是其他厂商的，再销售时不能是同一个Class II变更许可，以下例外： 1.部分 D 未经许可的个人通信服务器-最低增益天线是需要检测最低能量高于本底噪声，除了最高增益外的所有类型。
军队各军衔的英文名称General of the Army 五星上将General 上将Lieutenant General 中将Major General 少将Brigadier General 准将Colonel 上校Lieutenant Colonel 中校Major 少校Captain 上尉First Lieutenant 中尉Second Lieutenant 少尉Chief Warrant Officer 一级准尉Warrant Officer 二级准尉Master Sergeant 军士长Sergeant First Class 上士Sergeant 中士Corporal 下士Private First Class 一等兵Private 二等兵Basic Private 三等兵军衔的英文名称Army 陆军Field Marshal 元帅General of the Army 五星上将General 上将Lieutenant General 中将Major General 少将Brigadier 准将Colonel 上校Lieutenant Colonel 中校Major 少校Captain 上尉Lieutenant 中尉Second Lieutenant 少尉Warrant Officer (Class I) 一级准尉Warrant Officer (ClassII) 二级准尉Staff Sergeant 上士Sergeant 中士Corporal 下士Lance Corporal 一等兵Private 二等兵Recruit 新兵Air Force 空军Marshal of the Royal Air Force 元帅Air Chief Marshal 上将Air Marshal 中将Air Vice Marshal 少将Air Commodore 准将Group Captain 上校Wing Commander 中校Squadron Leader 少校Flight Lieutenant 上尉Flying Officer 中尉Pilot Officer 少尉Warrant Officer (Class I) 一级准尉Warrant Officer (Class II) 二级准尉Flight Sergeant 上士Sergeant 中士Corporal 下士Senior Aircraftman 一等兵Leading Aircraftman 二等兵Aircraftman 新兵Navy 海军Admiral of the Fleet 元帅Admiral 上将Vice Admiral 中将Rear Admiral 少将Commodore 准将Captain 上校Commander 中校Lieutenant Commander 少校Lieutenant 上尉Sublieutenant 中尉Acting Sublieutenant 少尉Warrant Officer (Class I) 一级准尉Warrant Officer (Class II) 二级准尉Chief Petty Officer 上士Petty Officer First Class 中士Petty Officer Second Class 下士Leading Seaman 一等兵Able Seaman 二等兵Ordinary Seaman 新兵Marine Corps 海军陆战队General 上将Lieutenant General 中将Major General 少将Brigadier 准将Colonel 上校Lieutenant Colonel 中校Major 少校Captain 上尉Lieutenant 中尉Second Lieutenant 少尉Warrant Officer (Class I) 一级准尉Warrant Officer (Class II) 二级准尉Colour Sergeant 上士Sergeant 中士Corporal 下士Marine First Class 一等兵Marine Second Class 二等兵Recruit 新兵双语：中国军衔等级及其英文名称陆军一级上将General First Class上将General中将Lieutenant General少将Major General大校Senior Colonel上校Colonel中校Lieutenant Colonel少校Major上尉captain中尉First Lieutenant少尉Second Lieutenant军士长Master Sergeant专业军士Speicalist Sergeant上士Sergeant, First Class中士Sergeant下士Corporal上等兵Private, First Class列兵Private海军一级上将Admiral, First Class上将Admiral中将Vice Admiral少将Rear Admiral大校Senior captain上校captain中校Commander少校Lieutenant Commander上尉Lieutenant中尉Lieutenant, Junior Grade少尉Ensign军士长Chief Petty Officer专业军士Special Petty Officer上士Petty Officer, First Class中士Petty Officer, Second Class下士Petty Officer, Third Class上等兵Seaman, First Class列兵Seaman, Second Class空军一级上将General, First Class上将General中将Lieutenant General少将Major General大校Senior Colonel少校Major上尉Captain中尉First Lieutenant少尉Second Lieutenant军士长Master Sergeant专业军士Specialist Sergeant上士Technical Sergeant中士Staff Sergeant下士Sergeant上等兵Airman, First Class列兵Airman, Second Class_________________________________________________________________________。
诺基亚手机外观检验规范1 目的 Purpose规范诺基亚产品的外观检验标准，制定诺基亚手机产品的外观检验之缺陷判定基准，使生产者、检验员或相关人员能正确、更快地掌握产品的检验标准，确保产品品质，满足客户要求。
Define cosmetic criteria of Nokia mobile phone product, Define defect determining baseline of Nokia mobile phone product cosmetic inspection, let producer, inspector can understand product inspection criteria correctly and quickly. To ensure product quality, satisfy customer’s requirement.2 适用范围：Application适用于手机产品的外观检验.Apply to cosmetic inspection for Nokia.3 参考文件：ReferenceAL-18-G-0007 MOSS 800/1 - Visual Quality of Mechanics 机构件外观品质标准AL-18-G-0006 MOSS 800/2 - Quality Standard of Painted Parts 喷漆件品质标准AL-18-G-0008 MOSS 800/4 - Quality Standard for Aluminium and Magnesium Die Casting铝镁压铸产品品质标准AL-18-G-0010 MOSS 800/7 - Quality Standard for Injection Molded Plastic Parts注塑塑胶产品品质标准<<SY B/C-Cover Painting 3D Drawing>> SY B/C-Cover 3D喷漆图面4 定义 Definition4.1 缺陷定义: Defect Definition:4.1.1 严重缺陷：凡制品有危及使用者或生产者生命安全之缺陷，谓之严重缺陷。
The Class-I AmplifierThe Class-I Amplifier I类放大器Class-I, also known as BCA (Balanced Current Amplifier) is Crown’s patented, cutting-edge technology that gets more power out of an amplifier with less waste than was ever before possible.I类，也被称为BCA（平衡电流放大器）皇冠的专利，尖端的技术，获得了更多的放大器功率输出，减少浪费比以前可能。
Class-I technology offers several key advantages. It provides unprecedented efficiency, requiring less power from the AC supply than other designs and that can add up to significant cost savings over the life of the amplifier. Class-I handles reactive loudspeaker loads easily and gracefully, by reusing energy returned from the loudspeaker rather than dissipating it as heat or forcing the amp into premature current limiting. This characteristic means class-I amplifiers run better and longer— especially at lower impedances. It also makes them more reliable, since they are not constantly stressed to their limits or subjected to excessive heat. Best of all, as proud owners can attest, amplifiers with class-I technology sound great, with a powerful, accurate sound that stands out from the competition.I类技术提供了一些关键的优势。
CERTIFICATE LIST FOR 广珠/GUANG ZHUNO FORM TITLES OF CERTIFICATE VALIDITY REMARKS1 CLSi(C) 临时入级证书INTERIM CLASSIFICATION CERTIFICATEINTERIMCLSa(C) 临时入级证书附页APPENDIX TO CLASSIFICATION CERTIFICATEPHc 压载舱涂层状况表SUMMARY OF COATING CONDITION IN SALT WATER TANKS/HOLDS AND EXAMINATION REQUIREMENTS2 CSCi(CHN)货船构造安全证书CARGO SHIP SAFETY CONSTRUCTION CERTIFICATEINTERIM3 CSEi /E/CEXi(CHN)货船设备安全证书/格式E/免除证书CARGO SHIP SAFETY EQUIPMENT CERTIFICATE& FORM E & EXEMPTION CERTIFICATEINTERIM4 CSRi / R(CHN)货船无线电安全证书/格式RCARGO SHIP SAFETY RADIO CERTIFICATE & FORM RINTERIM5 COPi / A(CHN)国际防止油污染证书/格式AINTERNATIONAL OIL POLLUTION PREVENTION CERTIFICATE &FORM AINTERIM6 CWPi(CHN)国际防止生活污水污染证书INTERNATIONAL SEWAGE POLLUTION PREVENTIONCERTIFICAREINTERIM7 CGP 防止船舶垃圾污染检验证明STATEMENT OF GARBAGE POLLUTION PREVENTION FROMSHIPSFULL TERM8 CAPi /AIR(CHN)国际防止空气污染证书/格式AIRINTERNATIONAL AIR POLLUTION PREVENTION& FORM AIR(CHN)INTERIM9CLLi(CHN)国际载重线证书INTERNATIONAL LOAD LINE CERTIFICATEINTERIM10CITi(CHN)国际吨位证书（1969）INTERNATIONAL TONNAGE CERTIFICATE(1969)INTERIM11 CST-2 /RST-2苏伊士运河吨位证书/苏伊士运河吨位丈量数据表SUEZ CANAL SPECIAL TONNAGE CERTIFICATE &CALCULATION BOOKLET FOR SUEZ CANAL TONNAGEMEASUREMENTFULL TERM12 CPCT 巴拿马运河吨位证明文件PC/UMS DOCUMENTATION OF TOTAL VOLUM FOR PANAMACANALFULL TERM13 CBCi 固体散装货物适装证明CERTIFICATE OF COMPLIANCE FOR THE CARRIAGE OF SOLIDBULK CARGOESINTERIM14 CCG-1 谷物适装证明DOCUMENT OF AUTHORIZATION FOR CARRIAGE OF GRAIN INBULKFULL TERM15 CCA 船员舱室设备检验证书CERTIFICATE OF INSPECTION OF CREW ACCOMODATIONFULL TERM16 SAF /RAF国际防污底系统符合证明/防污底系统记录STATEMENT OF COMPLIANCE WITH ANTI-FOULING SYSTEM &RECORD OF ANTI-FOULING SYSTEMFULL TERM17 RLA 船舶起重和起货设备检验簿REGISTER OF SHIP’S LIFTING APPLIANCES AND CARGOHANDLING GEARFULL TERMCLA 起重设备检验和试验证书CERTIFICATE OF TEST AND EXAMINATION OF LIFTINGAPPLIANCESFULL TERMCLG 活动零部件检验和试验证书CERTIFICATE OF TEST AND EXAMINATION OF LOOSE GEARFULL TERM格式FormCLSi(C)CHINA CLASSIFICATION SOCIETY中 国 船 级 社编号No.NJ08NB00029June 30, 2009Jiangyin 兹证明上述船舶的船体、轮机及设备业经中国船级社进行了检验并符合本社规范和规则的要求，建议但应持续符合本社规范和规则的各项要求。
叫我第一名的观后感英文篇一：叫我第一名的英文读后感Feeing after watching Front of the classI cried twice when I watched this movie. That scene that all the students applaud for Brad to show their understanding is still clear in my mind. At that moment,my eyes are full of tears. Also, there are many scene that moved me. Now,I want to share two aspect about this movie to you.The first thing that I want to talk about is the education.I remember a principal i this movie had ever asked a question to Brad: “what is education?”when all of the teacher in his school show their unfriendly and blame to Brad, it is this principal that give him courage and help him to open a new world. It is he that make Brad be understood and treated equal by other students. Besides, it is he that make Brad determined to become a teacher. This is a pawer of education and real education. Education is not like the way that those teacher used to treat Brad and the attitude that take different from different students. On the contrary, Brad do what a real teacher do. He contribute all his life to the teaching the momentwhen he determined to be a teacher. He take every lesson with high passion and all his enthusiasm. His principle of teaching is not giving up every student. He also make students can’t wait to take his class due to his creative teaching method so that they can easily understand the content of the book. That’s really a admirable teacher. He regard teaching as an important part in his life. This spirit that Brad showed is what every teacher should learn.Second, I want to talk about the quality of Brad.he is a disabled man but more optimistic than anyone. He isn’t ashamed to talk about his syndrome. In contrast he confront it bravely and see it as his friend. He hold his dream intensively just like he said to the children: “I will what I want to do not what I can do.”it occur to me a sentence I read “the only place where your dream becomes impossible is in your own heart.”Last ,I want to tell myself that no matter how difficult things you may meet, your dream will come true as long as you stick to it!篇二：英语读后感——叫我第一名I am so happy to watch such a wonderful movie. It’s the best inspirational movie I have ever seen.Brad Cohen is the held who was born with a disease called “Tourette syndrome”. The film is original from a real story of BradCohen. Almost everyone can’t put up with his bad disease for he is just always making terrible noises wherever he is, even his father. However, his mother never gives him up. She tells him not to be sad and concentrate on his study, eventually he made it, and he successfully graduated from a famous college. Although he graduated from a famous college, everyhead teacher said the same word “We will concern your matter, we will reply you soon”. His illness has been a trouble again in front of his development.During this moment, he may think he can’t be a successful man or he will give up to be a teacher, butfinally, he chooses fighting.Eventually, he got the job teaching primary school. He was full of passion and taught students by heart. All the people around him were proud of him. At the same time, he fell in love with a good girl who understood and accepted him.The film tells us never give up whatever you have met. Trust your life is the most important thing, your lift will never fade if you keep on trying. Life is like a box of chocolate, you will never know what you take next. There are some classic lines that I want to share with you:1.I will never forget it. These people were Tourette syndrome defeated, I never do this。
三类ivd注册流程英文回答：IVD (In Vitro Diagnostic) registration refers to the process of obtaining regulatory approval for in vitro diagnostic devices. There are three main categories of IVD registration processes, which are based on the risk classification of the device. These categories include Class I, Class II, and Class III.1. Class I IVD Registration:Class I IVD devices are considered to have the lowest risk and are typically simple devices. The registration process for Class I devices is relatively straightforward and involves submitting a registration application to the regulatory authority. This application includes information about the device, its intended use, and any supporting data or documentation. Once the application is reviewed and approved, the device can be legally marketed and sold.For example, if I want to register a Class I IVD device for measuring blood glucose levels, I would need to provide information about the device's design, intended use, and performance characteristics. I might also need to provide clinical data or studies that demonstrate the device's accuracy and reliability.2. Class II IVD Registration:Class II IVD devices are considered to have a moderate risk and may require additional regulatory controls. The registration process for Class II devices is more complex and involves a thorough review of the device's safety and effectiveness. In addition to the registration application, manufacturers of Class II devices may need to provide clinical data, performance evaluations, and quality management system documentation.For example, if I want to register a Class II IVD device for detecting infectious diseases, I would need to provide evidence that the device is accurate and reliable.This might include clinical studies comparing the device's results to a gold standard method, as well as documentation of the device's manufacturing processes and quality control procedures.3. Class III IVD Registration:Class III IVD devices are considered to have the highest risk and are typically complex devices that are used for diagnosing or monitoring serious conditions. The registration process for Class III devices is the most rigorous and involves a comprehensive review of thedevice's safety, effectiveness, and performance. Manufacturers of Class III devices may need to provide extensive clinical data, including data from clinical trials, as well as evidence of the device's manufacturing processes and quality control systems.For example, if I want to register a Class III IVD device for detecting cancer biomarkers, I would need to provide a substantial amount of clinical data demonstrating the device's accuracy and effectiveness. This would likelyinclude data from large-scale clinical trials involving patients with known cancer diagnoses, as well as evidence of the device's manufacturing processes and quality control systems.中文回答：IVD（体外诊断）注册流程是指获取体外诊断设备监管批准的过程。
初二英语Unit 1 Me and My Class （I）冀教版【本讲教育信息】一. 教学内容：Unit 1 Me and My Class（I）1. 单词。
back grade student class pupil cousinphoto wish either glad Ms. Mrs.Mr Miss blouse really also dislikehate interest violin music comb (be) marriedjeans weekend wool cotton2. 短语。
be back 回来have lessons/class 上课look like 看上去像take a picture 照相be made of 由……制成be ready to do 准备做……write down 记下 a piece of paper 一张纸play the violin 拉小提琴3. 句型。
I like...best.I like going for walks.It’s made of.…4. 交际用语。
I like to wear my red coat.Sandra likes going for walks.Sandra loves to eat many different foods.I don’t like my pictureI dislike Mondays.I hate rain.I hate getting out of bed sometimes.I hate to comb my hair.二. 重点、难点解析及词语辨析：1. Mr. , Mrs. , Ms. , Miss 的用法。
这些词一般放在姓前，也可以放在姓名之前。
Mr. 可用于某些男子职务的称呼。
例如：Mr. Chairman （主席先生）Mrs. 用于已婚女子，例如：Mrs. Brown （布朗夫人）Miss 用于未婚女子，例如：Miss Green （格林小姐）Ms.在不知已婚还是未婚的情况下使用，译成女士。
22.1 范围：本章适用于以下几点（1）易燃和可燃液体的储存量如3.3.30和第四章中定义，在固定的地上储罐中如3.3.47.1中所定义。
（2）易燃和可燃液体在移动储罐和散货集装箱中的储量超过793gal（3000L）（3）此类罐和移动储罐及散货集装箱的安装和操作22.2 对22章的具体定义：出于本章的目的，以下术语将如下定义22.2.1浮顶储罐：一个地面储罐包含以下一种设计：1）一个按照API标准650建造的敞篷罐有一个闭顶浮桥或者双层金属浮顶，钢焊接储油罐。
2）按照API标准650建造的含通风的固定金属顶和储罐顶檐，并且包含一个满足API标准650的闭顶浮桥或双层金属浮顶3）按照API标准650建造的有通风的固体金属罐顶和顶檐包含一个金属浮顶由液压金属浮力装置提供浮力来保证当一半的浮力中心已经失去时避免液体表面暴露在外。
22.2.1.1 出于本章的目的，一个有不满足22.1.1要求的内部金属浮盘，顶或盖子的储罐，或者某个为了漂浮用了塑料泡沫，即使是压缩金属或玻璃纤维，都应满足一个固顶罐的要求。
22.3 保存22.4 地面储罐的位置22.4.1 位置遵守建筑红线，公共道路，重要楼宇22.4.1.1 用来存放I级II级IIIA级静态液体，内部压力不允许超过17kPa示压的储罐应如表22.4.1.1.（a）和表22.4.1.1.（b）安置。
其中罐间距是基于罐顶-罐壁弱焊缝而设计的，使用者需出示证据证明建设管理局已要求管辖。
22.4.1.2 罐顶-罐壁弱焊缝的垂直罐（见22.7.2），储存IIIA级液体，需要表22.4.1.1（a）中具体距离的1.5倍才能被允许放置。
表22.4.1.1（a）所提供的是不同围垦面积或在排放路径上的储存I级和II级液体的储罐。
表22.4.1.1（a）储存静态液体的地上储罐的位置---------内部压力不超过示压2.5psi（17kPa）Ft=0.3 m；1 gal=3.8 L22.4.1.3储存Class I，Class II，或Class IIIA稳定液体的罐和工作压力超过2.5psi（17kPa）表压，或配备紧急排气压力可允许超过2.5psi表压（17kPa），应按照表22.4.1.3和表22.4.1.1（b）来安置。
The Class-I AmplifierThe Class-I Amplifier I类放大器Class-I, also known as BCA (Balanced Current Amplifier) is Crown’s patented, cutting-edge technology that gets more power out of an amplifier with less waste than was ever before possible.I类，也被称为BCA（平衡电流放大器）皇冠的专利，尖端的技术，获得了更多的放大器功率输出，减少浪费比以前可能。
Class-I technology offers several key advantages. It provides unprecedented efficiency, requiring less power from the AC supply than other designs and that can add up to significant cost savings over the life of the amplifier. Class-I handles reactive loudspeaker loads easily and gracefully, by reusing energy returned from the loudspeaker rather than dissipating it as heat or forcing the amp into premature current limiting. This characteristic means class-I amplifiers run better and longer— especially at lower impedances. It also makes them more reliable, since they are not constantly stressed to their limits or subjected to excessive heat. Best of all, as proud owners can attest, amplifiers with class-I technology sound great, with a powerful, accurate sound that stands out from the competition.I类技术提供了一些关键的优势。
它提供了前所未有的效率，需要更少的功率比其他的设计和从交流电源，可以添加显着的成本节约的整个生命周期的放大器。
I类可以轻松地处理活性扬声器负载优雅，再利用能源，返回的扬声器而不是散热热或迫使过早电流安培的电流限制。
这种特性I类放大器运行得更好和更特别在较低的阻抗。
这也使得他们更加可靠，因为他们不经常强调他们的限制或受到过多的热量。
最重要的是，作为引以为傲的业主可以证明，I类放大器与技术提供了强大的，准确的声音，声音很大，脱颖而出的竞争。
Crown’s class-I “switching” technology is a completely new adaptation of switching (PWM) amplifier design. This paper provides a simplified overview of Class-I, but before we explore its inner-workings, we need to look at the foundation of all previous high-power amplifier designs in order to fully appreciate how class-I stands apart.皇冠的I类“切换”技术是一种完全新的适应切换（PWM）放大器的设计。
本文提供了一个简单的概述I类，但在我们探讨它的内部运作，我们需要看看以前所有的高功率放大器设计的基础为了充分了解I类代表分开。
TRANSISTOR OPERATION晶体管工作To understand the different amplifier classes, it helps to understand a little about how transistors operate. Bias is a technical term referring to the static operating condition of an electronic device, such as a transistor. In other words, bias defines how much conduction takes place in the transistor with no dynamic signal input. Transistors may operate in three possible states: cutoff, saturation, or somewhere in between. The cutoff state is when there is not enough signal present to cause the device to conduct. Saturation refers to when the device has reached maximum conductivity. Amplifiers referred to as “dissipative” control their output by operating in the region between cutoff and saturation.要了解不同的放大器类，它有助于了解了一些有关如何晶体管的运行。
偏差是一个技术术语，指的静态工作条件的电子器件，诸如晶体管。
在其他也就是说，偏差定义了多少传导发生在晶体管的与没有动态信号输入。
晶体管可以操作在三种可能的状态：截止，饱和度，或介于两者之间。
截止状态时有还没有足够的信号存在导致的移动设备以进行。
饱和度是指已经达到时，该设备最大的传导性。
放大器称为“耗散”在该地区，控制其输出的操作截止和饱和度之间。
CLASS-A A类Class-A amplifiers are the simplest in design, and can be the most distortion-free of all amplifier classes. In class-A, the output devices are biased on all the time with a current large enough to produce the largest output signal.A类放大器是最简单的设计，并能是最无失真的放大器类。
在A级，输出设备是偏颇的，所有的时间与电流的足够大，以产生最大的的输出信号。
Some class-A amplifiers may employ both a positive and negative device in a push-pullarrangement to increase output power, but both devices still are biased一些A类放大器可以采用积极的和负的移动设备中的推挽安排提高输出功率，但二者之间仍然有偏见Class-A Operationon and conduct all the time. Class-A amplifiers are generally considered to be the most accurate of all classes in low to moderate power ranges and are useful for applications such as preamp stages; however, they create tremendous amounts of heat due to their very low efficiency, making them impractical for high-power amplification. Other amplifier classes have been developed over time to overcome the class-A efficiency problem.并进行所有的时间。
A类放大器通常被认为是最准确的类在低到中等功率范围和有用的的应用程序，诸如前置放大器阶段，但是，它们创造了巨大的热量，由于其非常低的效率，使他们不切实际的高功率放大。
其他的放大器类已经开发随着时间的推移，克服了A级效率问题。
CLASS-B AND TIME ALTERNATION B类和时间交替Class-B was invented as a solution to the efficiency problem with class-A. The invention of class-B is significant in that with it came the concept of time alternation, which has been the foundation of virtually all power amplifier designs used for audio reproduction and industrial power since about 1931 to the present. While many incremental improvements have been brought to market since that time, none have varied from the basic time-alternation paradigm.作为一个解决办法，效率发明B类A类的问题。
B类是本发明的显着的在与时间交替的概念来，这一直是基础，几乎所有的电源放大器设计用于音频再现和工业功率约自1931年到现在。
而许多增量改进已被带到市场自那时以来，还没有从基本的变化时间交替范例。
The basic class-B amplifier implements two devices in the output stage in a “push-pull” arrangement, with each amplifying half of the waveform, and the devices operate in strict time alternation. When the signal goes device is biased off. In turn, when the signal goes negative, the positive device biases off while the negative device turns on and conducts the negative portion of the signal.B类放大器的基本实现两台设备输出级中的“推 - 拉”的安排，与每个放大波形的一半，并且设备操作在严格的时间交替。
