(Speaker John Bercow)President Obama Addresses the British Parliament

(Speaker John Bercow)President Obama Addresses the British Parliament
(Speaker John Bercow)President Obama Addresses the British Parliament

Speaker John Bercow :

Mr. President, ladies and gentlemen, history is more than the path left by the past. It influences the present and can shape the future. We meet today in Westminster Hall, a building begun 900 years ago when the Vikings were visiting the shores of what would become the United States, even if it was Columbus who would subsequently demonstrate the politician's art of arriving late, but claiming all the credit. (laughter) This hall has witnessed grim trials in the sentencing to death of a king, coronation banquets, ceremonial addresses, and the coffins of those receiving the last respects of our people. Few places reach so far into the heart of our nation. Yet until today, no American president has stood on these steps to address our country's Parliament. It is my honor, Mr. President, to welcome you as our friend and as a statesman. Statesmanship is the cement which seals our shared idealism as nations. It makes meaningful the unity of ambition, passion for freedom, and abhorrence of injustice that is the call of our close alliance. It has fallen to you to tackle economic turbulence at home, to protect the health of those without wealth, and to seek that precious balance between security which is too often threatened, and human rights which are too often denied. History is not the burden of any one man or woman alone. But some are called to meet a special share of it's challenges. It is a duty that you

discharge with a dignity, determination, and distinction that are widely admired. Abraham Lincoln once observed that nearly all men can stand adversity. But if you want to test a man's character, give him power. Ladies and gentlemen, the President of the United States of America, Barack Obama. (applause)

President Obama:

Thank you very much. (applause) Thank you very much. Thank you. (applause) Thank you. (applause) Thank you so much. (applause) My Lord Chancellor, Mr. Speaker, Mr. Prime Minister, my lords, and members of the House of Commons: I have known few greater honors than the opportunity to address the Mother of Parliaments at Westminster Hall. I am told that the last three speakers here have been the Pope, Her Majesty the Queen, and Nelson Mandela -- which is either a very high bar or the beginning of a very funny joke. (laughter) I come here today to reaffirm one of the oldest, one of the strongest alliances the world has ever known. It's long been said that the United States and the United Kingdom share a special relationship. And since we also share an especially active press corps, that relationship is often analyzed and overanalyzed for the slightest hint of stress or strain. Of course, all relationships have their ups and downs. Admittedly, ours got off on the wrong foot with a small scrape

about tea and taxes. (laughter) There may also have been some hurt feelings when the White House was set on fire during the War of 1812. (laughter) But fortunately, it's been smooth sailing ever since. The reason for this close friendship doesn't just have to do with our shared history, our shared heritage; our ties of language and culture; or even the strong partnership between our governments. Our relationship is special because of the values and beliefs that have united our people through the ages. Centuries ago, when kings, emperors, and warlords reigned over much of the world, it was the English who first spelled out the rights and liberties of man in the Magna Carta. It was here, in this very hall, where the rule of law first developed, courts were established, disputes were settled, and citizens came to petition their leaders. Over time, the people of this nation waged a long and sometimes bloody struggle to expand and secure their freedom from the crown. Propelled by the ideals of the Enlightenment, they would ultimately forge an English Bill of Rights, and invest the power to govern in an elected parliament that's gathered here today. What began on this island would inspire millions throughout the continent of Europe and across the world. But perhaps no one drew greater inspiration from these notions of freedom than your rabble-rousing colonists on the other side of the Atlantic. As Winston Churchill said, the "...Magna Carta, the Bill of

Rights, Habeas Corpus, trial by jury, and English common law find their most famous expression in the American Declaration of Independence." For both of our nations, living up to the ideals enshrined in these founding documents has sometimes been difficult, has always been a work in progress. The path has never been perfect. But through the struggles of slaves and immigrants, women and ethnic minorities, former colonies and persecuted religions, we have learned better than most that the longing for freedom and human dignity is not English or American or Western -- it is universal, and it beats in every heart. Perhaps that's why there are few nations that stand firmer, speak louder, and fight harder to defend democratic values around the world than the United States and the United Kingdom. We are the allies who landed at Omaha and Gold, who sacrificed side by side to free a continent from the march of tyranny, and help prosperity flourish from the ruins of war. And with the founding of NATO -- a British idea -- we joined a transatlantic alliance that has ensured our security for over half a century. Together with our allies, we forged a lasting peace from a cold war. When the Iron Curtain lifted, we expanded our alliance to include the nations of Central and Eastern Europe, and built new bridges to Russia and the former states of the Soviet Union. And when there was strife in the Balkans, we worked together to keep the peace. Today,

after a difficult decade that began with war and ended in recession, our nations have arrived at a pivotal moment once more. A global economy that once stood on the brink of depression is now stable and recovering. After years of conflict, the United States has removed 100,000 troops from Iraq, the United Kingdom has removed its forces, and our combat mission there has ended. In Afghanistan, we've broken the Taliban's momentum and will soon begin a transition to Afghan lead. And nearly 10 years after 9/11, we have disrupted terrorist networks and dealt al Qaeda a huge blow by killing its leader -- Osama bin Laden. Together, we have met great challenges. But as we enter this new chapter in our shared history, profound challenges stretch out before us. In a world where the prosperity of all nations is now inextricably linked, a new era of cooperation is required to ensure the growth and stability of the global economy. As new threats spread across borders and oceans, we must dismantle terrorist networks and stop the spread of nuclear weapons, confront climate change and combat famine and disease. And as a revolution races through the streets of the Middle East and North Africa, the entire world has a stake in the aspirations of a generation that longs to determine its own destiny. These challenges come at a time when the international order has already been reshaped for a new century. Countries like China, India, and Brazil are growing by leaps and

bounds. We should welcome this development, for it has lifted hundreds of millions from poverty around the globe, and created new markets and opportunities for our own nations. And yet, as this rapid change has taken place, it's become fashionable in some quarters to question whether the rise of these nations will accompany the decline of American and European influence around the world. Perhaps, the argument goes, these nations represent the future, and the time for our leadership has passed. That argument is wrong. The time for our leadership is now. It was the United States and the United Kingdom and our democratic allies that shaped a world in which new nations could emerge and individuals could thrive. And even as more nations take on the responsibilities of global leadership, our alliance will remain indispensable to the goal of a century that is more peaceful, more prosperous and more just. At a time when threats and challenges require nations to work in concert with one another, we remain the greatest catalysts for global action. In an era defined by the rapid flow of commerce and information, it is our free market tradition, our openness, fortified by our commitment to basic security for our citizens, that offers the best chance of prosperity that is both strong and shared. As millions are still denied their basic human rights because of who they are, or what they believe, or the kind of government that they live under, we are the nations most willing to

stand up for the values of tolerance and self-determination that lead to peace and dignity. Now, this doesn't mean we can afford to stand still. The nature of our leadership will need to change with the times. As I said the first time I came to London as President, for the G20 summit, the days are gone when Roosevelt and Churchill could sit in a room and solve the world's problems over a glass of brandy -- although I'm sure that Prime Minister Cameron would agree that some days we could both use a stiff drink. (laughter) In this century, our joint leadership will require building new partnerships, adapting to new circumstances, and remaking ourselves to meet the demands of a new era. That begins with our economic leadership. Adam Smith's central insight remains true today: There is no greater generator of wealth and innovation than a system of free enterprise that unleashes the full potential of individual men and women. That's what led to the Industrial Revolution that began in the factories of Manchester. That is what led to the dawn of the Information Age that arose from the office parks of Silicon Valley. That's why countries like China, India and Brazil are growing so rapidly -- because in fits and starts, they are moving toward market-based principles that the United States and the United Kingdom have always embraced. In other words, we live in a global economy that is largely of our own making. And today, the competition for the best jobs and industries

favors countries that are free-thinking and forward-looking; countries with the most creative and innovative and entrepreneurial citizens. That gives nations like the United States and the United Kingdom an inherent advantage. For from Newton and Darwin to Edison and Einstein, from Alan Turing to Steve Jobs, we have led the world in our commitment to science and cutting-edge research, the discovery of new medicines and technologies. We educate our citizens and train our workers in the best colleges and universities on Earth. But to maintain this advantage in a world that's more competitive than ever, we will have to redouble our investments in science and engineering, and renew our national commitments to educating our workforces. We've also been reminded in the last few years that markets can sometimes fail. In the last century, both our nations put in place regulatory frameworks to deal with such market failures -- safeguards to protect the banking system after the Great Depression, for example; regulations that were established to prevent the pollution of our air and our water during the 1970s. But in today's economy, such threats of market failure can no longer be contained within the borders of any one country. Market failures can go global, and go viral, and demand international responses. A financial crisis that began on Wall Street infected nearly every continent, which is why we must keep working through forums like the G20 to put in

place global rules of the road to prevent future excesses and abuse. No country can hide from the dangers of carbon pollution, which is why we must build on what was achieved at Copenhagen and Cancun to leave our children a planet that is safer and cleaner. Moreover, even when the free market works as it should, both our countries recognize that no matter how responsibly we live in our lives, hard times or bad luck, a crippling illness or a layoff may strike any one of us. And so part of our common tradition has expressed itself in a conviction that every citizen deserves a basic measure of security -- health care if you get sick, unemployment insurance if you lose your job, a dignified retirement after a lifetime of hard work. That commitment to our citizens has also been the reason for our leadership in the world. And now, having come through a terrible recession, our challenge is to meet these obligations while ensuring that we're not consuming -- and hence consumed -- with a level of debt that could sap the strength and vitality of our economies. And that will require difficult choices and it will require different paths for both of our countries. But we have faced such challenges before, and have always been able to balance the need for fiscal responsibility with the responsibilities we have to one another. And I believe we can do this again. As we do, the successes and failures of our own past can serve as an example for emerging economies -- that

it's possible to grow without polluting; that lasting prosperity comes not from what a nation consumes, but from what it produces, and from the investments it makes in its people and its infrastructure. And just as we must lead on behalf of the prosperity of our citizens, so we must safeguard their security. Our two nations know what it is to confront evil in the world. Hitler's armies would not have stopped their killing had we not fought them on the beaches and on the landing grounds, in the fields and on the streets. We must never forget that there was nothing inevitable about our victory in that terrible war. It was won through the courage and character of our people. Precisely because we are willing to bear its burden, we know well the cost of war. And that is why we built an alliance that was strong enough to defend this continent while deterring our enemies. At its core, NATO is rooted in the simple concept of Article Five: that no NATO nation will have to fend on its own; that allies will stand by one another, always. And for six decades, NATO has been the most successful alliance in human history. Today, we confront a different enemy. Terrorists have taken the lives of our citizens in New York and in London. And while al Qaeda seeks a religious war with the West, we must remember that they have killed thousands of Muslims -- men, women and children -- around the globe. Our nations are not and will never be at war with Islam. Our fight is focused on defeating

al Qaeda and its extremist allies. In that effort, we will not relent, as Osama bin Laden and his followers have learned. And as we fight an enemy that respects no law of war, we will continue to hold ourselves to a higher standard -- by living up to the values, the rule of law and due process that we so ardently defend. For almost a decade, Afghanistan has been a central front of these efforts. Throughout those years, you, the British people, have been a stalwart ally, along with so many others who fight by our side. Together, let us pay tribute to all of our men and women who have served and sacrificed over the last several years -- for they are part of an unbroken line of heroes who have borne the heaviest burden for the freedoms that we enjoy. Because of them, we have broken the Taliban's momentum. Because of them, we have built the capacity of Afghan security forces. And because of them, we are now preparing to turn a corner in Afghanistan by transitioning to Afghan lead. And during this transition, we will pursue a lasting peace with those who break free of al Qaeda and respect the Afghan constitution and lay down arms. And we will ensure that Afghanistan is never a safe haven for terror, but is instead a country that is strong, sovereign, and able to stand on its own two feet. Indeed, our efforts in this young century have led us to a new concept for NATO that will give us the capabilities needed to meet new threats -- threats like terrorism and piracy, cyber attacks

and ballistic missiles. But a revitalized NATO will continue to hew to that original vision of its founders, allowing us to rally collective action for the defense of our people, while building upon the broader belief of Roosevelt and Churchill that all nations have both rights and responsibilities, and all nations share a common interest in an international architecture that maintains the peace. We also share a common interest in stopping the spread of nuclear weapons. Across the globe, nations are locking down nuclear materials so they never fall into the wrong hands -- because of our leadership. From North Korea to Iran, we've sent a message that those who flaunt their obligations will face consequences -- which is why America and the European Union just recently strengthened our sanctions on Iran, in large part because of the leadership of the United Kingdom and the United States. And while we hold others to account, we will meet our own obligations under the Non-Proliferation Treaty, and strive for a world without nuclear weapons. We share a common interest in resolving conflicts that prolong human suffering and threaten to tear whole regions asunder. In Sudan, after years of war and thousands of deaths, we call on both North and South to pull back from the brink of violence and choose the path of peace. And in the Middle East, we stand united in our support for a secure Israel and a sovereign Palestine. And we share a common interest in development that

advances dignity and security. To succeed, we must cast aside the impulse to look at impoverished parts of the globe as a place for charity. Instead, we should empower the same forces that have allowed our own people to thrive: We should help the hungry to feed themselves, the doctors who care for the sick. We should support countries that confront corruption, and allow their people to innovate. And we should advance the truth that nations prosper when they allow women and girls to reach their full potential. We do these things because we believe not simply in the rights of nations; we believe in the rights of citizens. That is the beacon that guided us through our fight against fascism and our twilight struggle against communism. And today, that idea is being put to the test in the Middle East and North Africa. In country after country, people are mobilizing to free themselves from the grip of an iron fist. And while these movements for change are just six months old, we have seen them play out before -- from Eastern Europe to the Americas, from South Africa to Southeast Asia. History tells us that democracy is not easy. It will be years before these revolutions reach their conclusion, and there will be difficult days along the way. Power rarely gives up without a fight -- particularly in places where there are divisions of tribe and divisions of sect. We also know that populism can take dangerous turns -- from the extremism of those who would use

democracy to deny minority rights, to the nationalism that left so many scars on this continent in the 20th century. But make no mistake: What we saw, what we are seeing in Tehran, in Tunis, in Tahrir Square, is a longing for the same freedoms that we take for granted here at home. It was a rejection of the notion that people in certain parts of the world don't want to be free, or need to have democracy imposed upon them. It was a rebuke to the worldview of al Qaeda, which smothers the rights of individuals, and would thereby subject them to perpetual poverty and violence. Let there be no doubt: The United States and United Kingdom stand squarely on the side of those who long to be free. And now, we must show that we will back up those words with deeds. That means investing in the future of those nations that transition to democracy, starting with Tunisia and Egypt -- by deepening ties of trade and commerce; by helping them demonstrate that freedom brings prosperity. And that means standing up for universal rights -- by sanctioning those who pursue repression, strengthening civil society, supporting the rights of minorities. We do this knowing that the West must overcome suspicion and mistrust among many in the Middle East and North Africa -- a mistrust that is rooted in a difficult past. For years, we've faced charges of hypocrisy from those who do not enjoy the freedoms that they hear us espouse. And so to them, we must squarely

acknowledge that, yes, we have enduring interests in the region -- to fight terror, sometimes with partners who may not be perfect; to protect against disruptions of the world's energy supply. But we must also insist that we reject as false the choice between our interests and our ideals; between stability and democracy. For our idealism is rooted in the realities of history -- that repression offers only the false promise of stability, that societies are more successful when their citizens are free, and that democracies are the closest allies we have. It is that truth that guides our action in Libya. It would have been easy at the outset of the crackdown in Libya to say that none of this was our business -- that a nation's sovereignty is more important than the slaughter of civilians within its borders. That argument carries weight with some. But we are different. We embrace a broader responsibility. And while we cannot stop every injustice, there are circumstances that cut through our caution -- when a leader is threatening to massacre his people, and the international community is calling for action. That's why we stopped a massacre in Libya. And we will not relent until the people of Libya are protected and the shadow of tyranny is lifted. We will proceed with humility, and the knowledge that we cannot dictate every outcome abroad. Ultimately, freedom must be won by the people themselves, not imposed from without. But we can and must stand with those who so

struggle. Because we have always believed that the future of our children and grandchildren will be better if other people's children and grandchildren are more prosperous and more free -- from the beaches of Normandy to the Balkans to Benghazi. That is our interests and our ideals. And if we fail to meet that responsibility, who would take our place, and what kind of world would we pass on? Our action -- our leadership -- is essential to the cause of human dignity. And so we must act -- and lead -- with confidence in our ideals, and an abiding faith in the character of our people, who sent us all here today. For there is one final quality that I believe makes the United States and the United Kingdom indispensable to this moment in history. And that is how we define ourselves as nations. Unlike most countries in the world, we do not define citizenship based on race or ethnicity. Being American or British is not about belonging to a certain group; it's about believing in a certain set of ideals -- the rights of individuals, the rule of law. That is why we hold incredible diversity within our borders. That's why there are people around the world right now who believe that if they come to America, if they come to New York, if they come to London, if they work hard, they can pledge allegiance to our flag and call themselves Americans; if they come to England, they can make a new life for themselves and can sing God Save The Queen just like any other citizen. Yes, our

diversity can lead to tension. And throughout our history there have been heated debates about immigration and assimilation in both of our countries. But even as these debates can be difficult, we fundamentally recognize that our patchwork heritage is an enormous strength -- that in a world which will only grow smaller and more interconnected, the example of our two nations says it is possible for people to be united by their ideals, instead of divided by their differences; that it's possible for hearts to change and old hatreds to pass; that it's possible for the sons and daughters of former colonies to sit here as members of this great Parliament, and for the grandson of a Kenyan who served as a cook in the British Army to stand before you as President of the United States. (applause) That is what defines us. That is why the young men and women in the streets of Damascus and Cairo still reach for the rights our citizens enjoy, even if they sometimes differ with our policies. As two of the most powerful nations in the history of the world, we must always remember that the true source of our influence hasn't just been the size of our economies, or the reach of our militaries, or the land that we've claimed. It has been the values that we must never waver in defending around the world -- the idea that all beings are endowed by our Creator with certain rights that cannot be denied. That is what forged our bond in the fire of war -- a bond made manifest by the

friendship between two of our greatest leaders. Churchill and Roosevelt had their differences. They were keen observers of each other's blind spots and shortcomings, if not always their own, and they were hard-headed about their ability to remake the world. But what joined the fates of these two men at that particular moment in history was not simply a shared interest in victory on the battlefield. It was a shared belief in the ultimate triumph of human freedom and human dignity -- a conviction that we have a say in how this story ends. This conviction lives on in their people today. The challenges we face are great. The work before us is hard. But we have come through a difficult decade, and whenever the tests and trials ahead may seem too big or too many, let us turn to their example, and the words that Churchill spoke on the day that Europe was freed: "In the long years to come, not only will the people of this island but...the world, wherever the bird of freedom chirps in the human heart, look back to what we've done, and they will say 'do not despair, do not yield... march straightforward.'" With courage and purpose, with humility and with hope, with faith in the promise of tomorrow, let us march straightforward together, enduring allies in the cause of a world that is more peaceful, more prosperous, and more just. Thank you very much. (applause) Speaker: Mr. President, I think that response describes far more eloquently than any words of mine could do how

much that very memorable and inspiring address was appreciated by everybody who heard it here today. You spoke -- (applause) You spoke with great warmth and great generosity about the British Parliament and the British people and about the links that bind us, the values and the traditions that we share. The history that we have experienced together. But more than that, you spoke too not just of the relationships of the past, but the relationships of the future. And I think that was what made what you said so inspirational. It was a distinguished American governor of New York who remarked on the propensity of politicians to campaign in poetry, but to govern in prose. The world you described to us today was not just one that is prosaic; it was one where the challenges are difficult and sometimes dangerous. One that is fast moving, that is complex, sometimes contradictory. And that offers at least as many threats as opportunities. But in the eloquence of your address, you reminded us of the importance of maintaining the poetry in government. Because to lead, that poetry is necessary. Necessary not only to articulate the challenges, as you did so masterfully. But also to bring others together to face those challenges with common principles and with shared purpose. Mr. President, it has been a privilege for all of us to hear you speak today. It is a privilege for me to have the responsibility of thanking you on behalf of both Houses of Parliament,

for coming to Westminster, and to wish you and Mrs. Obama a very happy and pleasant rest of your stay in the United Kingdom. Thank you so much.

教你学会看手机电路图轻松修手机

第一篇、教你学会看电路图轻松修手机 一、一套完整的主板电路图,是由主板原理图和主板元件位置图组成的。 1.主板原理图,如图: 2.主板元件位置图,如图:

主板元件位置图的作用:是方便用户找到相应元件所在主板的正确位置。而主板原理图是让用户对主板的电路原理有所了解,知道各个芯片的功能,及其线路的连接。 二、相关名词解释 电路图中会涉及到许多英文标识,这些标识主要起到了辅助解图的作用,如果不了解它们,根本不知道他们的作用,也就根本不可能看得懂原理图。所以在这里我们会将主要的英文标识进行解释。希望大家能够背熟记熟,同时希望大家多看电路图,对不懂的英文及时查找记熟。 如图:

以上英文标识在电路图上会灵活出现,比如“扬声器”是“SPEAKER” ,它的缩写就是“SPK”,“正极”是“positive” ,缩写是“P” ,那么如果在图中标记SPKP,那么就证明它是扬声器正极。所以当有英文不明白的时候,可以将它们拆开后再进行理解,请大家灵活运用。

第二节主板元件位置图 一、元件编号 每一个元件在主板元件位置图中,都有一个唯一的编号。这个编号由英文字母和数字共同组成。编号规则可以分成以下几类: 芯片类:以U 为开头,如CPU U101 接口类:以J 为开头,如键盘接口J1202 三极管类:以Q 为开头,如三极管Q1206 二级管类:以D 为开头,如二极管D1102 晶振类:以X 为开头,如26M 晶体X901 电阻类:以R 或VR(压敏电阻)为开头,如电阻R32 VR211 电容类:以C 为开头,如电容C101 电感类:以L 为开头,如电感L1104 侧键类:以S 为开头,如侧键S1201 电池类:以 B 为开头,如备用电池B201 屏蔽罩:以SH 为开头,如屏蔽罩SH1 振动器:以M 为开头,如振子M201 还有一部分标号是主板上的测试点,以TP 为开头。 二、查找元件功能 用户可以根据相应的元件编号去查找主板原理图,从而了解此元件的作用。随便拿块主板作为示例。 如果想了解某一个元件的主要功能(图中红圈内元件) 如图:

手机电路原理,通俗易懂

第二部分原理篇 第一章手机的功能电路 ETACS、GSM蜂窝手机是一个工作在双工状态下的收发信机。一部移动电话包括无线接收机(Receiver)、发射机(Transmitter)、控制模块(Controller)及人机界面部分(Interface)和电源(Power Supply)。 数字手机从电路可分为,射频与逻辑音频电路两大部分。其中射频电路包含从天线到接收机的解调输出,与发射的I/Q调制到功率放大器输出的电路;逻辑音频包含从接收解调到,接收音频输出、发射话音拾取(送话器电路)到发射I/Q调制器及逻辑电路部分的中央处理单元、数字语音处理及各种存储器电路等。见图1-1所示 从印刷电路板的结构一般分为:逻辑系统、射频系统、电源系统,3个部分。在手机中,这3个部分相互配合,在逻辑控制系统统一指挥下,完成手机的各项功能。 图1-1手机的结构框图 注:双频手机的电路通常是增加一些DCS1800的电路,但其中相当一部分电路是DCS 与GSM通道公用的。 第二章射频系统 射频系统由射频接收和射频发射两部分组成。射频接收电路完成接收信号的滤波、信号放大、解调等功能;射频发射电路主要完成语音基带信号的调制、变频、功率放大等功能。手机要得到GSM系统的服务,首先必须有信号强度指示,能够进入GSM网络。手机电路中不管是射频接收系统还是射频发射系统出现故障,都能导致手机不能进入GSM网络。 对于目前市场上爱立信、三星系列的手机,当射频接收系统没有故障但射频发射系统有故障时,手机有信号强度值指示但不能入网;对于摩托罗拉、诺基亚等其他系列的手机,不管哪一部分有故障均不能入网,也没有信号强度值指示。当用手动搜索网络的方式搜索网络时,如能搜索到网络,说明射频接收部分是正常的;如果不能搜索到网络,首先可以确定射频接收部分有故障。 而射频电路则包含接收机射频处理、发射机射频处理和频率合成单元。 第一节接收机的电路结构 移动通信设备常采用超外差变频接收机,这是因为天线感应接收到的信号十分微弱,而鉴频器要求的输人信号电平较高,且需稳定。放大器的总增益一般需在120dB以上,这么大的放大量,要用多级调谐放大器且要稳定,实际上是很难办得到的,另外高频选频放大器的通带宽度太宽,当频率改变时,多级放大器的所有调谐回路必须跟着改变,而且要做到统一调谐,

手机供电电路与工作原理

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手机常用的充电控制原理电路图

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2、C218手机不充电(无充电电流) 处理方法:拆机后发现卡座下面一个黄电容(C324)有点变色,更换C324后无效。用万用表测ZD703开路,更换ZD703后故障有所改善(显示充电,但是充不进电)。分析原因应是CPU检测到充电信号,但是充电 IC没有完成充电电路中供电输出信号,更换充电IC(U301)后故障排除。 图3 3、D508手机装电池显示自动充电状态 处理方法:因为手机CPU检测到充电信号导致,先检查尾插正常,装电池测充电IC(U503)#7电压为低电平(正常2.6V左右)。查找电路图,发现U503#7与Q500相连,拆除Q500测量电压正 常,更换Q500故障排除。D508手机装电池显示自动充电的比较常见,有部份是充电IC或尾插 损坏导致,部分是由于Q500导致,但有部分Q500本身没有坏,但摘除Q500也可以解决。 图4 4、E738手机装电池按开机键即显示充电状态,不开机 处理方法:因为手机CPU检测到充电信号导致,先检查尾插正常,装电池测充电IC(U502)#3电压为低电平(正常2.6V左右)。查找电路图,发现U502#3与电源IC(U400)#1相连,更换电源IC后故障排除。(原理分析参照图1) 5、E368手机充电时会提示"USB不能充电" 处理方法:插入充电器,测量U502#2(USB充电输入)有2.2V(正常为0V,只有采用USB充电时才会有 5.0V输入),测U502#1与#2阻值偏低,更换充电控制管U502后故障排除。(原理分析参照图1) 6、E808手机自动充电

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卡器支持近30家银行信用卡的还款业务,并且大多数银行实时到账且无手续费。在操作上也极为简单,用户只需输入手机号码、还款金额、分别刷信用卡和储蓄卡便可完成还款。 使用手机刷卡器的主要事项: 1.不能长时间将手机刷卡器插在手机上,这样手机刷卡器会持续消耗电池电量,很快没电,需要更换电池。 2.测试手机刷卡器时尽量平稳的插入手机刷卡器,并将手机音量开到最大。 3.使用手机刷卡器的时候必须输入正确的序列号。 4.如若使用不了的时候请检查是否电池电量已经耗尽。可到手表维修店铺购买CR2032纽扣电池替换。 5.刷卡器磁道较短,请确保刷卡时让整个磁条通过磁道中的磁头。 6.当第一次注册成功并输入刷卡器时,手机帐号和刷卡机序列号就会绑定在一起,只有这个刷卡器能使用账户充值功能。插入其他刷卡器不能使用。 7.应避免同一个刷卡器短时间内插入多个手机使用,公司后台可能会锁死刷卡器不能使用。 8.应避免同一个手机短时间内插入多个刷卡机使用,公司后台可能会锁死刷卡器不能使用。 9.注册成功后,确认刷卡器使用正常后,务必7天内点击软件里的“用户认证”,上传身份证原件到公司后台,否则7天后手机刷卡器会用不了。 那么手机刷卡器怎么使用呢,怎么样才能实现手机刷卡,缴费成功呢?其实手机刷卡器是操作非常简单,跟POS刷卡相似,再简单不过了。在说手机刷卡器只用之前,不得不说一下支撑手机刷卡完成的不大部分:智能手机、刷卡器客户端。手机刷卡器、刷卡器支持的银行卡。

手机的工作原理

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手机工作原理

手机工作原理 -标准化文件发布号:(9556-EUATWK-MWUB-WUNN-INNUL-DDQTY-KII

手机饰品的闪光原理 #1 一、CDMA手机饰品的闪光原理为什么中国移动GSM手机饰品挂在中国联通CDMA手机上不闪光这要从CDMA和GSM手机的工作原理谈起,GSM手机是采取将语音打包压缩后发射出去的,也就是说间隙脉冲工作的,工作时提高发射功率来保持语音清晰,其余时间不发射。而CDMA手机基台采用了定向天线系统,当基台发现有手机要工作时,便会启动定向系统指向手机所在的方向并计算手机最经济的发射功率,使手机发射功率维持在比较低的水平,也就是说CDMA手机系统是充分利用基台的定向系统优势,而让手机工作在小功率状态(这就是大家看到的CDMA手机的电池容量可以比GSM手机容量小而使用时间长的原因)。这样CDMA手机系统便可采用连续工作的方式发射信号,而不像GSM手机脉冲工作方式那样工作时大功率发射。目前市面上手机饰品是为GSM手机设计的,也就是说利用了GSM手机脉冲工作时大功率发射信号来触发IC闪光的。但对于CDMA手机GSM手机饰品就不会闪光了。本公司在充分研究CDMA手机系统后,开发了CDMA手机闪光饰品,她能在CDMA手机工作时触发专用IC闪光。这是目前世界上真正的第一款CDMA手机来电闪光饰品。二、手机贴纸的闪光原理当手机向基台传送信号时,手机发射的是很强的电磁波。根据电磁理论,电磁波在空中遇到天线,在天线的中段就会产生电压和电流。闪光贴纸其实就是一根接收天线,它把手机的电磁波信号变为电压和电流导致发光。但是为什么只有NOKIA的手机使用贴纸效果最好呢因为由于此类型的手机没有采用标准的高效率螺旋天线,为了达到通话清晰和不掉线的效果,此类手机设计时就增大了手机的发射功率。这也是此类手机电池不够其它手机电池使用时间长的原因。三、GSM手机饰品的闪光原理手机使用时,手机是一部信号发射接收器,不停地和基台进行接收和发射的交换。手机闪光饰品中有一块具有检测手机信号发射接收的专用IC,当接检测到手机有信号时,就启动IC工作―-发光或发声等等。早期的闪光吊饰采用的是通用IC,需要加外围电路来检测手机的信号,这样做体积大,不适用产品的小型化。而现在把检测手机信号的外围电路和闪光IC集成一起。 GSM手机工作原理简介 图1 FDMA、TDMA及CDMA之间的对照图 GSM是采用FDMA(频分)与TDMA(时分)制式相结合的一种通信技术,其网络中所有用户分时使用不同的频率进行通信。在GSM900频段,25MHZ的频率范围划分为124个不同的信道,每个信道带宽为200K,每个信道含8个时隙,即GSM900M频段在同一区域内,可同时供近1000个用户使用。而CDMA是采用码分多址技术的一种通信系统,在这个系统中所有用户都使用同一频率。FDMA、TDMA及CDMA的比较如图2.1. 一、GSM的理论基础. GSM系统是第二代数字蜂窝移动通信系统,它采用900MHz频段,在后期又加入了1800MHz频段及1900MHz频段,为便于区别,分别称为GSM900、DCS1800及PCS1900. 凌锐手机具有GSM900MHz及DCS1800MHz两个频段自动切换的功能. 初期的GSM的工作频率是890~915MHz(移动台发),935~960MHz(基站发)共25MHz的双工频率;后加入了EGSM(扩展GSM)其频段为880~890MHz(移动台发),925~935MHz(基站发),为与EGSM区别,把前者称之为PGSM。GSM900上行与下行频段的间隔为45MHz,信道间隔为200KHz,可分为124个信道(EGSM加入了975~1023共49个信道);因此E-GSM共有174个信道。 DCS1800的频段为1710~1785MHz(移动台发),1805~1880MHz(基站发),上行与下行频段的间隔为95MHz,频带宽度为75M,可分为374个信道(512至885)。 PCS1900的频段分为上行:1850~1910MHz,下行:1930~1990MHz,上行与下行频段的间隔为80MHz,频带宽度为60M,可分为300个信道。 每信道分成8个时隙(半速率是有16个),每个时隙信道速率是22.8kb/s,信道总传输速率270.83Kb/s,采用GMSK调制,通信方式是全双工,分集接收,每秒跳

手机电路结构详细介绍

第一章手机的功能电路 ETACS、GSM蜂窝手机是一个工作在双工状态下的收发信机。一部移动电话包括无线接收机(Receiver)、发射机(Transmitter)、控制模块(Controller)及人机界面部分(Interface)和电源(Power Supply)。 数字手机从电路可分为,射频与逻辑音频电路两大部分。其中射频电路包含从天线到接收机的解调输出,与发射的I/Q调制到功率放大器输出的电路;逻辑音频包含从接收解调到,接收音频输出、发射话音拾取(送话器电路)到发射I/Q调制器及逻辑电路部分的中央处理单元、数字语音处理及各种存储器电路等。见图1-1所示 从印刷电路板的结构一般分为:逻辑系统、射频系统、电源系统,3个部分。在手机中,这3个部分相互配合,在逻辑控制系统统一指挥下,完成手机的各项功能。 图1-1手机的结构框图 注:双频手机的电路通常是增加一些DCS1800的电路,但其中相当一部分电路是DCS 与GSM通道公用的。 第二章射频系统 射频系统由射频接收和射频发射两部分组成。射频接收电路完成接收信号的滤波、信号放大、解调等功能;射频发射电路主要完成语音基带信号的调制、变频、功率放大等功能。手机要得到GSM系统的服务,首先必须有信号强度指示,能够进入GSM网络。手机电路中不管是射频接收系统还是射频发射系统出现故障,都能导致手机不能进入GSM网络。 对于目前市场上爱立信、三星系列的手机,当射频接收系统没有故障但射频发射系统有故障时,手机有信号强度值指示但不能入网;对于摩托罗拉、诺基亚等其他系列的手机,不管哪一部分有故障均不能入网,也没有信号强度值指示。当用手动搜索网络的方式搜索网络时,如能搜索到网络,说明射频接收部分是正常的;如果不能搜索到网络,首先可以确定射频接收部分有故障。 而射频电路则包含接收机射频处理、发射机射频处理和频率合成单元。 第一节接收机的电路结构 移动通信设备常采用超外差变频接收机,这是因为天线感应接收到的信号十分微弱,而鉴频器要求的输人信号电平较高,且需稳定。放大器的总增益一般需在120dB以上,这么大的放大量,要用多级调谐放大器且要稳定,实际上是很难办得到的,另外高频选频放大器的通带宽度太宽,当频率改变时,多级放大器的所有调谐回路必须跟着改变,而且要做到统一调谐,这是难于做到的。超外差接收机则没有这种问题,它将接收到的射频信号转换成固定的中频,其主要增益得自于稳定的中频放大器。

手机工作原理详解

手机工作原理详解 一般来说,我们普通用户只要学会如何使用好手机就可以了,对于其具体的工作原理不必仔细深究;然而在使用手机的过程中,由于各种因素的影响,手机不可避免地要出现故障,如果每次遇到故障哪怕是最微小的,都送到专业维修店去修理,您可能会觉得麻烦。如果您有相当的电器知识的话,您可能想自己学着修理,但要学修理,必须先熟悉手机的工作原理,只有这样才能判断发生的故障原因,并找出相应的解决方法。同时,了解手机的工作原理对于普通人来说也可以作为一种知识的储备。为了能帮助这些喜爱手机的用户快速学会修理,笔者就以摩托罗拉手机为例,来详细介绍一下手机到底是如何工作的。 手机之所以能相互通信,笔者认为它是由三部分协调工作的结果,这三部分分别为射频部分、逻辑部分和电源部分,要了解手机的工作原理其实只要了解这三部分是如何工作的就可以了,下面笔者就对这三个部分的工作原理进行分别地介绍。 射频部分 通常射频部分,又是由接受信号部分和发送信号部分组成。手机在接受信号时,首先利用天线把接收到的935-960MHz的射频信号,经U400、SW363,将发射信号的接收信号分开,使收发互不干扰。从U400的第四脚输入第五脚输出,进入接收前端回路。U400的工作状态受第三脚电位的控制,而第三脚电位又受到来自CPU的TXON、RXON 信号的控制。经过天线开关的射频信号首先经过带通滤波器FL451的滤波,再送入高频放大管Q418进行放大,Q418的输出经FL452滤波后送Q420混频管进行混频。而本机振荡信号由RXVCO产生,并以FL453滤波后送Q420的基极进行混频,取其差额,从Q420的集电极输出153MHz的中频信号,经FL420滤波后得到153MHz纯净的中柴油机信号,现经Q421放大后送U201的31脚,153MHz的中频信号与153MHz 的载波信号在32D53内解调产生RXI和RXQ模拟基带信号,经U201的46#和48#送U501的14#和15#。在U501内经A/D转换后送数字信号处理器做进一步的处理。153MHz的载波由U201的41#、42#、43#接外围电路所构成的306MHz振荡电路,形成306MHz卉波信号,经二频后形成153MHz载波。对于发送部分,从501的21#、22#、23#、24#输出的TXIN、TXIP、TXQN、TXQP发射频带信号进入U201的61#、62#、63#、64#。U201的6#、7#、10#外接一个216MHz的VCO,产生216MHz的载波信号,该信号经U201内的分频器分频产生108MHz的发射中频信号。四路调制信号在U201内完成108MHz载波调制从第4脚输出到U300的4#。U300完成发射取样信号与TXVCO相温柔频,取其差额得108MHz信号与4#输入的TXIF鉴相,产生鉴相误差电压,从第8脚输出去控制变容二极管CR300的容量来改变TXVCO的振荡频率,从Q300的C极输出890-915MHz的发射信号经Q301前级放大和Q302推动后进入功放Q302,放大后的信号进入天线U400的第1脚,再从U400的4#送天线发射出去。

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