模擬電子技術(shù)實驗實驗課程報告

1、We will continue to improve the companys internal control system, and steady improvement in ability to manage and control, optimize business processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of ev

2、aluation complying with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full communication zero resistan

3、ce. To constantly perfect ERP, and BFS+, and PI, and MIS, and SCM, information system based construction, full integration information system, achieved information resources shared; to expand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to

4、perfect daily run maintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS+, and ERP, and SCM, technology application of training, improve employees application information system of capacity and level. Humanistic care to ensure zero. To strengthen

5、ing Humanities care, continues to foster company wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helped trapped, care difficult employees; carried out style activities, rich employees life; strengthening health and labour protection, organization career health medic

6、al, control career against; continues to implementation psychological warning prevention system, training employees health of character, and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. To strengthen risk management, ensure that the business of

7、zero risk. To strengthened business plans management, will business business plans cover to all level, ensure the business can control in control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to imple

8、mentation State-owned assets method, further specification business financial management; to perfect risk tube control system, achieved risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize

9、trading, and strive to achieve according to law, standardize and fair. Innovation of performance management, to ensure that potential employees zero fly. To strengthen performance management, process control, enhance employee evaluation and levels of effective communication to improve performance ma

10、nagement. To further quantify and refine employee standards . Work, full play party, and branch, and members in five type Enterprise construction in the of core role, and fighting fortress role and pioneer model role; to continues to strengthening four good leadership constructionWe will continue to

11、 improve the companys internal control system, and steady improvement in ability to manage and control, optimize business processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of evaluation complying

12、with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full communication zero resistance. To constantly p

13、erfect ERP, and BFS+, and PI, and MIS, and SCM, information system based construction, full integration information system, achieved information resources shared; to expand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to perfect daily run m

14、aintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS+, and ERP, and SCM, technology application of training, improve employees application information system of capacity and level. Humanistic care to ensure zero. To strengthening Humanities care

15、, continues to foster company wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helped trapped, care difficult employees; carried out style activities, rich employees life; strengthening health and labour protection, organization career health medical, control career

16、against; continues to implementation psychological warning prevention system, training employees health of character, and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. To strengthen risk management, ensure that the business of zero risk. To stren

17、gthened business plans management, will business business plans cover to all level, ensure the business can control in control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to implementation State-own

18、ed assets method, further specification business financial management; to perfect risk tube control system, achieved risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize trading, and strive

19、 to achieve according to law, standardize and fair. Innovation of performance management, to ensure that potential employees zero fly. To strengthen performance management, process control, enhance employee evaluation and levels of effective communication to improve performance management. To furthe

20、r quantify and refine employee standards . Work, full play party, and branch, and members in five type Enterprise construction in the of core role, and fighting fortress role and pioneer model role; to continues to strengthening four good leadership construction廣西工學(xué)院鹿山學(xué)院模擬電子線路實驗指導(dǎo)書利用設(shè)在基坑邊的固定泵輸送砼到施工面

21、，人工攤鋪，平板振搗器振搗密實，用刮杠沿模板頂將砼刮平，并用木抹搓平壓實，確保砼密實和表面平整。砼澆注時埋設(shè)支立模板及鋼筋支架所需預(yù)埋鐵件play levels cadres in enterprise development in the of backbone backbone role; to full strengthening members youth work, full play youth employees in company development in the of force role; to improve independent Commission again

22、st corruption work level, strengthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further strengthen publicity and education, improve the overall legal system. We must strengthen safety management, establish and improve the education, supervision, and e

23、valuation as one of the traffic safety management mechanism. To conscientiously sum up the Olympic security controls, promoting integrated management to a higher level, higher standards, a higher level of development. Employees, today is lunar calendar on December 24, the ox Bell is about to ring, a

24、t this time of year, we clearly feel the pulse of the XX power generation company to flourish, to more clearly hear XX power generation companies mature and symmetry breathing. Recalling past one another across a railing, we are enthusiastic and full of confidence. Future development opportunities,

25、we more exciting fight more spirited. Employees, let us together across 2013 full of challenges and opportunities, to create a green, low-cost operation, full of humane care of a world-class power generation company and work hard! The occasion of the Spring Festival, my sincere wish that you and the

26、 families of the staff in the new year, good health, happy, happy!PAGE 26利用設(shè)在基坑邊的固定泵輸送砼到施工面，人工攤鋪，平板振搗器振搗密實，用刮杠沿模板頂將砼刮平，并用木抹搓平壓實，確保砼密實和表面平整。砼澆注時埋設(shè)支立模板及鋼筋支架所需預(yù)埋鐵件play levels cadres in enterprise development in the of backbone backbone role; to full strengthening members youth work, full play youth emp

27、loyees in company development in the of force role; to improve independent Commission against corruption work level, strengthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further strengthen publicity and education, improve the overall legal system. We

28、 must strengthen safety management, establish and improve the education, supervision, and evaluation as one of the traffic safety management mechanism. To conscientiously sum up the Olympic security controls, promoting integrated management to a higher level, higher standards, a higher level of deve

29、lopment. Employees, today is lunar calendar on December 24, the ox Bell is about to ring, at this time of year, we clearly feel the pulse of the XX power generation company to flourish, to more clearly hear XX power generation companies mature and symmetry breathing. Recalling past one another acros

30、s a railing, we are enthusiastic and full of confidence. Future development opportunities, we more exciting fight more spirited. Employees, let us together across 2013 full of challenges and opportunities, to create a green, low-cost operation, full of humane care of a world-class power generation c

31、ompany and work hard! The occasion of the Spring Festival, my sincere wish that you and the families of the staff in the new year, good health, happy, happy!PAGE 27We will continue to improve the companys internal control system, and steady improvement in ability to manage and control, optimize busi

32、ness processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of evaluation complying with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline

33、, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full communication zero resistance. To constantly perfect ERP, and BFS+, and PI, and MIS, and SCM, information system based construction, full integration information s

34、ystem, achieved information resources shared; to expand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to perfect daily run maintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS+, and ERP

35、, and SCM, technology application of training, improve employees application information system of capacity and level. Humanistic care to ensure zero. To strengthening Humanities care, continues to foster company wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helpe

36、d trapped, care difficult employees; carried out style activities, rich employees life; strengthening health and labour protection, organization career health medical, control career against; continues to implementation psychological warning prevention system, training employees health of character,

37、 and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. To strengthen risk management, ensure that the business of zero risk. To strengthened business plans management, will business business plans cover to all level, ensure the business can control i

38、n control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to implementation State-owned assets method, further specification business financial management; to perfect risk tube control system, achieved

39、risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize trading, and strive to achieve according to law, standardize and fair. Innovation of performance management, to ensure that potential em

40、ployees zero fly. To strengthen performance management, process control, enhance employee evaluation and levels of effective communication to improve performance management. To further quantify and refine employee standards . Work, full play party, and branch, and members in five type Enterprise con

41、struction in the of core role, and fighting fortress role and pioneer model role; to continues to strengthening four good leadership construction利用設(shè)在基坑邊的固定泵輸送砼到施工面，人工攤鋪，平板振搗器振搗密實，用刮杠沿模板頂將砼刮平，并用木抹搓平壓實，確保砼密實和表面平整。砼澆注時埋設(shè)支立模板及鋼筋支架所需預(yù)埋鐵件play levels cadres in enterprise development in the of backbone back

42、bone role; to full strengthening members youth work, full play youth employees in company development in the of force role; to improve independent Commission against corruption work level, strengthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further

43、strengthen publicity and education, improve the overall legal system. We must strengthen safety management, establish and improve the education, supervision, and evaluation as one of the traffic safety management mechanism. To conscientiously sum up the Olympic security controls, promoting integrate

44、d management to a higher level, higher standards, a higher level of development. Employees, today is lunar calendar on December 24, the ox Bell is about to ring, at this time of year, we clearly feel the pulse of the XX power generation company to flourish, to more clearly hear XX power generation c

45、ompanies mature and symmetry breathing. Recalling past one another across a railing, we are enthusiastic and full of confidence. Future development opportunities, we more exciting fight more spirited. Employees, let us together across 2013 full of challenges and opportunities, to create a green, low

46、-cost operation, full of humane care of a world-class power generation company and work hard! The occasion of the Spring Festival, my sincere wish that you and the families of the staff in the new year, good health, happy, happy!實驗報告要求：一寫4個實驗報告，每個報告裝訂成一份，每人4份，不要將4個實驗報告裝訂成1份了。實驗一：常用電子儀器的使用。（包括示波器的使用、

47、萬用表的使用、函數(shù)信號發(fā)生器的使用等內(nèi)容）實驗二：晶體管共射極單管放大器實驗三：射極跟隨器實驗四：差動放大器二手寫報告，不得打印。三具體怎樣寫實驗報告，可參考大學(xué)物理實驗報告的要求。四3月26日前，收好后統(tǒng)一交給老師。模擬電子實驗指導(dǎo)書目 錄 TOC o 1-1 h z u HYPERLINK l _Toc 實驗一示波器原理及使用 PAGEREF _Toc h 2 HYPERLINK l _Toc 實驗二晶體管共射極單管放大器 PAGEREF _Toc h 12 HYPERLINK l _Toc 實驗三射極跟隨器 PAGEREF _Toc h 19 HYPERLINK l _Toc 實驗四差動

48、放大器 PAGEREF _Toc h 24實驗一示波器原理及使用一、示波器的基本結(jié)構(gòu)示波器的種類很多，但它們都包含下列基本組成部分，如附圖11 所示。附圖11 示波器的基本結(jié)構(gòu)框圖主機(jī)主機(jī)包括示波管及其所需的各種直流供電電路，在面板上的控制旋鈕有：輝度、聚焦、水平移位、垂直移位等。2、垂直通道垂直通道主要用來控制電子束按被測信號的幅值大小在垂直方向上的偏移。它包括Y軸衰減器，Y軸放大器和配用的高頻探頭。通常示波管的偏轉(zhuǎn)靈敏度比較低，因此在一般情況下，被測信號往往需要通過Y軸放大器放大后加到垂直偏轉(zhuǎn)板上， 才能在屏幕上顯示出一定幅度的波形。 Y軸放大器的作用提高了示波管Y軸偏轉(zhuǎn)靈敏度。為了保證Y

49、軸放大不失真，加到Y(jié)軸放大器的信號不宜太大，但是實際的被測信號幅度往往在很大范圍內(nèi)變化，此Y軸放大器前還必須加一Y軸衰減器，以適應(yīng)觀察不同幅度的被測信號。示波器面板上設(shè)有“Y軸衰減器”（通常稱“Y軸靈敏度選擇”開關(guān)）和“Y軸增益微調(diào)”旋鈕，分別調(diào)節(jié)Y 軸衰減器的衰減量和Y軸放大器的增益。對Y軸放大器的要求是：增益大，頻響好，輸入阻抗高。為了避免雜散信號的干擾，被測信號一般都通過同軸電纜或帶有探頭的同軸電纜加到示波器Y軸輸入端。但必須注意，被測信號通過探頭 幅值將衰減(或不衰減)，其衰減比為101(或11)。3、水平通道水平通道主要是控制電子束按時間值在水平方向上偏移。主要由掃描發(fā)生器、水平放大

50、器、觸發(fā)電路組成。掃描發(fā)生器掃描發(fā)生器又叫鋸齒波發(fā)生器，用來產(chǎn)生頻率調(diào)節(jié)范圍寬的鋸齒波，作為X 軸偏轉(zhuǎn)板的掃描電壓。鋸齒波的頻率（或周期）調(diào)節(jié)是由“掃描速率選擇”開關(guān)和“掃速微調(diào)”旋鈕控制的。使用時，調(diào)節(jié)“掃速選擇”開關(guān)和“掃速微調(diào)”旋鈕，使其掃描周期為被測信號周期的整數(shù)倍，保證屏幕上顯示穩(wěn)定的波形。水平放大器其作用與垂直放大器一樣，將掃描發(fā)生器產(chǎn)生的鋸齒波放大到X軸偏轉(zhuǎn)板所需的數(shù)值。觸發(fā)電路用于產(chǎn)生觸發(fā)信號以實現(xiàn)觸發(fā)掃描的電路。為了擴(kuò)展示波器應(yīng)用范圍，一般示波器上都設(shè)有觸發(fā)源控制開關(guān)，觸發(fā)電平與極性控制旋鈕和觸發(fā)方式選擇開關(guān)等。二、示波器的二蹤顯示二蹤顯示原理示波器的二蹤顯示是依靠電子開關(guān)的

51、控制作用來實現(xiàn)的。電子開關(guān)由“顯示方式”開關(guān)控制，共有五種工作狀態(tài)，即Y1、Y2、Y1Y2、交替、斷續(xù)。當(dāng)開關(guān)置于“交替”或“斷續(xù)”位置時，熒光屏上便可同時顯示兩個波形。當(dāng)開關(guān)置于“交替”位置時，電子開關(guān)的轉(zhuǎn)換頻率受掃描系統(tǒng)控制，工作過程如附圖12所示。即電子開關(guān)首先接通Y2通道，進(jìn)行第一次掃描，顯示由Y2通道送入的被測信號的波形；然后電子開關(guān)接通Y1通道，進(jìn)行第二次掃描，顯示由Y1通道送入的被測信號的波形；接著再接通Y2通道這樣便輪流地對Y2和Y1兩通道送入的信號進(jìn)行掃描、顯示，由于電子開關(guān)轉(zhuǎn)換速度較快，每次掃描的回掃線在熒光屏上又不顯示出來，借助于熒光屏的余輝作用和人眼的視覺暫留特性，使用

52、者便能在熒光屏上同時觀察到兩個清晰的波形。這種工作方式適宜于觀察頻率較高的輸入信號場合。當(dāng)開關(guān)置于“斷續(xù)”位置時，相當(dāng)于將一次掃描分成許多個相等的時間間隔。在第一次掃描的第一個時間間隔內(nèi)顯示Y2信號波形的某一段；在第二個時間時隔內(nèi)顯示Y1信號波形的某一段；以后各個時間間隔輪流地顯示Y2、Y1兩信號波形的其余段，經(jīng)過若干次斷續(xù)轉(zhuǎn)換，使熒光屏上顯示出兩個由光點組成的完整波形如附圖13(a)所示。由于轉(zhuǎn)換的頻率很高，光點靠得很近，其間隙用肉眼幾乎分辨不出，再利用消隱的方法使兩通道間轉(zhuǎn)換過程的過渡線不顯示出來,見附圖13(b)，因而同樣可達(dá)到同時清晰地顯示兩個波形的目的。這種工作方式適合于輸入信號頻率

53、較低時使用。 附圖1-2 交替方式顯示波形 附圖1-3 斷續(xù)方式顯示波形2、觸發(fā)掃描在普通示波器中，X軸的掃描總是連續(xù)進(jìn)行的，稱為“連續(xù)掃描”。為了能更好地觀測各種脈沖波形，在脈沖示波器中，通常采用“觸發(fā)掃描”。采用這種掃描方式時，掃描發(fā)生器將工作在待觸發(fā)狀態(tài)。它僅在外加觸發(fā)信號作用下，時基信號才開始掃描，否則便不掃描。這個外加觸發(fā)信號通過觸發(fā)選擇開關(guān)分別取自“內(nèi)觸發(fā)”（Y軸的輸入信號經(jīng)由內(nèi)觸發(fā)放大器輸出觸發(fā)信號），也可取自“外觸發(fā)”輸入端的外接同步信號。其基本原理是利用這些觸發(fā)脈沖信號的上升沿或下降沿來觸發(fā)掃描發(fā)生器，產(chǎn)生鋸齒波掃描電壓，然后經(jīng)X軸放大后送X軸偏轉(zhuǎn)板進(jìn)行光點掃描。適當(dāng)?shù)卣{(diào)節(jié)“

54、掃描速率”開關(guān)和“電平”調(diào)節(jié)旋鈕，能方便地在熒光屏上顯示具有合適寬度的被測信號波形。上面介紹了示波器的基本結(jié)構(gòu)，下面將結(jié)合使用介紹電子技術(shù)實驗中常用的CA8020型雙蹤示波器。三、CA8020型雙蹤示波器1、概述CA8020型示波器為便攜式雙通道示波器。本機(jī)垂直系統(tǒng)具有020MHz的頻帶寬度和5mV/DIV5V/DIV的偏轉(zhuǎn)靈敏度，配以101探極，靈敏度可達(dá)5V/DIV。本機(jī)在全頻帶范圍內(nèi)可獲得穩(wěn)定觸發(fā)，觸發(fā)方式設(shè)有常態(tài)、自動、TV和峰值自動，尤其峰值自動給使用帶來了極大的方便。內(nèi)觸設(shè)置了交替觸發(fā)，可以穩(wěn)定地顯示兩個頻率不相關(guān)的信號。本機(jī)水平系統(tǒng)具有0.5S/DIV0.2S/DIV的掃描速度，

55、并設(shè)有擴(kuò)展10，可將最快掃速度提高到20nS/DIV。2、面板控制件介紹CA8020面板圖如附圖14所示附圖14CA8020型雙蹤示波器面板圖序號控制件名稱功能（1）亮度調(diào)節(jié)光跡的亮度（2）輔助聚焦與聚焦配合，調(diào)節(jié)光跡的清晰度（3）聚焦調(diào)節(jié)光跡的清晰度（4）跡線旋轉(zhuǎn)調(diào)節(jié)光跡與水平刻度線平行（5）校正信號提供幅度為0.5V，頻率為1KHz的方波信號，用于校正101探極的補(bǔ)償電容器和檢測示波器垂直與水平的偏轉(zhuǎn)因數(shù)（6）電源指示電源接通時，燈亮（7）電源開關(guān)電源接通或關(guān)閉（8）CH1移位PULL CH1XCH2Y調(diào)節(jié)通道1光跡在屏幕上的垂直位置，用作XY顯示（9）CH2移位PULL INVERT調(diào)節(jié)

56、通道2光跡在屏幕上的垂直位置，在ADD方式時使CH1CH2或CH1CH2（10）垂直方式CH1或CH2：通道1或通道2單獨顯示ALT：兩個通道交替顯示CHOP：兩個通道斷續(xù)顯示，用于掃速較慢時的雙蹤顯示ADD：用于兩個通道的代數(shù)和或差（11）垂直衰減器調(diào)節(jié)垂直偏轉(zhuǎn)靈敏度（12）垂直衰減器調(diào)節(jié)垂直偏轉(zhuǎn)靈敏度（13）微調(diào)用于連續(xù)調(diào)節(jié)垂直偏轉(zhuǎn)靈敏度，順時針旋足為校正位置（14）微調(diào)用于連續(xù)調(diào)節(jié)垂直偏轉(zhuǎn)靈敏度，順時針旋足為校正位置（15）耦合方式(AC-DC-GND)用于選擇被測信號饋入垂直通道的耦合方式（16）耦合方式(AC-DC-GND)用于選擇被測信號饋入垂直通道的耦合方式（17）CH1ORX被

57、測信號的輸入插座（18）CH2 ORY被測信號的輸入插座（19）接地(GND)與機(jī)殼相聯(lián)的接地端（20）外觸發(fā)輸入外觸發(fā)輸入插座（21）內(nèi)觸發(fā)源用于選擇CH1、CH2或交替觸發(fā)（22）觸發(fā)源選擇用于選擇觸發(fā)源為INT（內(nèi)），EXT（外）或LINE（電源）（23）觸發(fā)極性用于選擇信號的上升或下降沿觸發(fā)掃描（24）電平用于調(diào)節(jié)被測信號在某一電平觸發(fā)掃描（25）微調(diào)用于連續(xù)調(diào)節(jié)掃描速度，順時針旋足為校正位置（26）掃描速率用于調(diào)節(jié)掃描速度（27）觸發(fā)方式常態(tài)（NORM）：無信號時，屏幕上無顯示；有信號時，與電平控制配合顯示穩(wěn)定波形。自動（AUTO）：無信號時，屏幕上顯示光跡；有信號時，與電平控制配合

58、顯示穩(wěn)定波形。電視場（TV）：用于顯示電視場信號。峰值自動（PPAUTO）：無信號時，屏幕上顯示光跡；有信號時，無須調(diào)節(jié)電平即能獲得穩(wěn)定波形顯示。（28）觸發(fā)指示在觸發(fā)掃描時，指示燈亮（29）水平移位PULL10調(diào)節(jié)跡線在屏幕上的水平位置拉出時掃描速度被擴(kuò)展10倍3、操作方法1)、電源檢查CA8020雙蹤示波器電源電壓為220V10%。接通電源前，檢查當(dāng)?shù)仉娫措妷海绻幌喾?，則嚴(yán)格禁止使用！2)、面板一般功能檢查A將有關(guān)控制件按下表置位控制件名稱作用位置控制件名稱作用位置亮度居中觸發(fā)方式峰值自動聚焦居中掃描速率0.5mS/div位移居中極性正垂直方式CH1觸 發(fā) 源INT靈敏度選擇10mV

59、/div內(nèi)觸發(fā)源CH1微調(diào)校正位置輸入耦合ACB接通電源，電源指示燈亮，稍預(yù)熱后，屏幕上出現(xiàn)掃描光跡，分別調(diào)節(jié)亮度、聚焦、輔助聚焦、跡線旋轉(zhuǎn)、垂直、水平移位等控制件，使光跡清晰并與水平刻度平行。C用101探極將校正信號輸入至CH1輸入插座。D調(diào)節(jié)示波器有關(guān)控制件，使熒光屏上顯示穩(wěn)定且易觀察方波波形。E將探極換至CH2輸入插座，垂直方式置于“CH2”，內(nèi)觸發(fā)源置于“CH2”，重復(fù)D操作。3)、垂直系統(tǒng)的操作A垂直方式的選擇當(dāng)只需觀察一路信號時，將“垂直方式”開關(guān)置“CH1”或“CH2”，此時被選中的通道有效，被測信號可從通道端口輸入。當(dāng)需要同時觀察兩路信號時，將“垂直方式”開關(guān)置“交替”，該方式

60、使兩個通道的信號被交替顯示，交替顯示的頻率受掃描周期控制。當(dāng)掃速低于一定頻率時，交替方式顯示會出現(xiàn)閃爍，此時應(yīng)將開關(guān)置于“斷續(xù)”位置。當(dāng)需要觀察兩路信號代數(shù)和時，將“垂直方式”開關(guān)置于“代數(shù)和”位置，在選擇這種方式時，兩個通道的衰減設(shè)置必須一致，CH2移位處于常態(tài)時為CH1CH2，CH2移位拉出時為CH1CH2。B輸入耦合方式的選擇直流（DC）耦合：適用于觀察包含直流成份的被測信號，如信號的邏輯電平和靜態(tài)信號的直流電平，當(dāng)被測信號的頻率很低時，也必須采用這種方式。交流（AC）耦合：信號中的直流分量被隔斷，用于觀察信號的交流份量，如觀察較高直流電平上的小信號。接地（GND）：通道輸入端接地（輸入