tag 标签: transmission

相关博文
  • 热度 28
    2015-6-12 18:17
    1565 次阅读|
    0 个评论
    “When I was a boy of 14, my father was so ignorant I could hardly stand to have the old man around. But when I got to be 21, I was astonished at how much the old man had learned in seven years.” — Mark Twain   When I was a young parent I knew pretty much everything about raising children. As time passed life and circumstances challenged many of those core beliefs. One of the most remarkable things about guiding kids from birth to adulthood is just how much the parent learns.   One of those key principles was that none of our kids would have a car in high school. Sure, they could use ours, but I felt owning a car would be a distraction that could lead to no good. After all, I wasn’t allowed to own a car till college, and what was good enough for me…   Yet some of my friends in high school had parents who were more tolerant. We worked on their cars. A lot. Rebuilt engines, swapped transmissions, did the brakes, etc. I learned an enormous amount about machinery by getting my hands greasy.   When he turned 16 my son asked if he could buy an old VW microbus. Hey, I had one in my twenties and even lived in it for a year while saving for a boat. My initial negative response was met with a carefully-reasoned argument about how much he would learn, and that, after all, these were so old they’d probably never run. Then he said he had saved $1200 doing summer jobs so could afford this.   I relented. He bought two junkers with a little financial help from us, both 1977 vintage, both with seized engines, one with a bad transmission, and both with lots of other problems.   In 1980, living in an apartment, I realized there were three VW engines in the living room and porch, all of which I was rebuilding for friends and family. After finishing those I swore I’d never do another. Now we had my son’s engines in the basement. The two of us spent a winter companionably rebuilding one, using parts from the other as well as new parts where needed (cylinders and pistons). We turned the two dead vehicles into one working one over the course of a year.   His friends all predicted failure; the bus would never be done. They saw those boxes of parts and couldn’t imagine how a working engine could emerge from the chaos. I kept telling him it was just an engine; we were a lot smarter than it. Each part has a purpose, a place, each bolt gets a certain torque, and the pieces, one at a time, would come together to form a working whole.   Parents of teenagers know how hard it can be to maintain a civil relationship with those morons young people. This project bound us closer and kept us talking in a positive way.   Today Graham is a physicist. Last year he replaced the engine and transmission in his jeep. He has a mastery of the intellectual domain as well as the mechanical world. The bus project was a big part of what gave him the knowledge and confidence to understand this technical world and to fix things.   I’d like to say, per the title of this piece, that all teenagers need this sort of experience, but the truth is that kids differ. My daughter never had the slightest interest in anything technical or mechanical. Despite the same opportunities, today she doesn’t know which end of a screwdriver to hold.   Over the last couple of months I’ve gotten a lot of “kids these days” emails from readers, lamenting a variety of problems with youth who are victims of technology rather than competent masters of it. Some complain about young engineers with little mechanical aptitude, or an attitude that if Google can’t return an answer quickly, there is no answer. I’m not keen on “kids these days” grumbling, as every generation has had the same complaint. Kids these days are, well, kids, and are still learning. In the workplace it’s our job to mentor them. In the family we need to provide them with learning opportunities.   For me ham radio, TV repair, and the like were gateways into electronics. But working on cars gave me mechanical competence. The maker movement, Arduino, and the like are wonderful ways to teach young folks about modern electronics. I do think a rounded individual should also understand how stuff works in general. How a piston does its thing. How air conditioning works. The difference between torque and horsepower.   The teenage years are very formative. Try to give your youngster opportunities to develop mastery of this very complex world, to feel confident about breaking out a toolbox rather than calling a handyman or AAA when something goes wrong.
相关资源
  • 所需E币: 1
    时间: 2022-9-30 19:49
    大小: 31.75MB
    上传者: 西风瘦马
    MITRadiationLaboratoryMicrowaveTransmissionCircuits.pdf
  • 所需E币: 3
    时间: 2022-6-6 16:11
    大小: 802.58KB
    上传者: xyzzyxaaa
    63基于TransmissionBuilder的减速器载荷预测及传动误差优化.pdf
  • 所需E币: 4
    时间: 2019-12-28 23:19
    大小: 40.56KB
    上传者: wsu_w_hotmail.com
    PowerSupplyFrom4-20mATransmissionLine……
  • 所需E币: 4
    时间: 2019-12-25 16:36
    大小: 14.59MB
    上传者: quw431979_163.com
    高速数字系统设计……
  • 所需E币: 4
    时间: 2019-12-24 22:22
    大小: 27.04KB
    上传者: 978461154_qq
    Abstract:Thisarticleshowsanexampleofimplementinga4-20mAor0-20mAcurrent-loopoutputusingavoltageoutputdigital-to-analogconverter(DAC)andaVtoIconverter.Maxim>AppNotes>A/DandD/ACONVERSION/SAMPLINGCIRCUITSAMPLIFIERANDCOMPARATORCIRCUITSSWITCHESANDMULTIPLEXERSKeywords:4-20mA,0-20mA,currentloop,currentlooptransmission,DAC,V/I,VtoI,converter,digitaltoMay31,2002analogconverterAPPLICATIONNOTE1085Selectable-RangeCurrentLoopAbstract:Thisarticleshowsanexampleofimplementinga4-20mAor0-20mAcurrent-loopoutputusingavoltageoutputdigital-to-analogconverter(DAC)andaVtoIconverter.Current-loopsignals,asopposedtovoltagesignals,arecommonlyusedinindustrialsystemsbecausetheyaremuchlesssubjecttonoiseandrelativelyindifferenttolinelength(becausethecurrentisunaffectedbylineresistance).ThecircuitofFigure1allowsdigitalselectionbetweenthetwostanda……
  • 所需E币: 4
    时间: 2019-12-24 22:21
    大小: 116.96KB
    上传者: 16245458_qq.com
    Abstract:Thisapplicationnoteexplains4–20mAcurrentloopsandintelligenttransmittersandexplainstheirneedforhigh-resolutionlow-powerDACs.Maxim>AppNotes>A/DandD/ACONVERSION/SAMPLINGCIRCUITSAMPLIFIERANDCOMPARATORCIRCUITSSIGNALGENERATIONCIRCUITSKeywords:4-20mA,currentloop,currentloops,DAC,ADC,currentDAC,isolation,2-wire,signalconditioning,Dec29,2000lowpower,D/A,industrialcontrol,EMI,transducers,currenttransmission,transmitterAPPLICATIONNOTE7223V/5VDACsSupportIntelligentCurrentLoopAbstract:Thisapplicationnoteexplains4-20mAcurrentloopsandintelligenttransmittersandexplainstheirneedforhigh-resolutionlow-powerDACs.Anoptimumpower-supplychipisnottheonlycriticalchoicetobemadeindesigningamixed3V/5Vmicroprocessor-controlledsystem.Becausemoreandmoresystemsrequirelow-powercomponentscapableoflow-voltagestartup,state-of-the-artA/……
  • 所需E币: 4
    时间: 2019-12-24 20:23
    大小: 116.96KB
    上传者: 微风DS
    智能变送器,并解释他们的需要高分辨率低功率DAC。Maxim>AppNotes>A/DandD/ACONVERSION/SAMPLINGCIRCUITSAMPLIFIERANDCOMPARATORCIRCUITSSIGNALGENERATIONCIRCUITSKeywords:4-20mA,currentloop,currentloops,DAC,ADC,currentDAC,isolation,2-wire,signalconditioning,Dec29,2000lowpower,D/A,industrialcontrol,EMI,transducers,currenttransmission,transmitterAPPLICATIONNOTE7223V/5VDACsSupportIntelligentCurrentLoopAbstract:Thisapplicationnoteexplains4-20mAcurrentloopsandintelligenttransmittersandexplainstheirneedforhigh-resolutionlow-powerDACs.Anoptimumpower-supplychipisnottheonlycriticalchoicetobemadeindesigningamixed3V/5Vmicroprocessor-controlledsystem.Becausemoreandmoresystemsrequirelow-powercomponentscapableoflow-voltagestartup,state-of-the-artA/……
  • 所需E币: 3
    时间: 2019-12-24 20:20
    大小: 27.04KB
    上传者: wsu_w_hotmail.com
    0-20mA的电流回路输出电压输出数字-模拟转换器(DAC)和一个I转换至五例如。Maxim>AppNotes>A/DandD/ACONVERSION/SAMPLINGCIRCUITSAMPLIFIERANDCOMPARATORCIRCUITSSWITCHESANDMULTIPLEXERSKeywords:4-20mA,0-20mA,currentloop,currentlooptransmission,DAC,V/I,VtoI,converter,digitaltoMay31,2002analogconverterAPPLICATIONNOTE1085Selectable-RangeCurrentLoopAbstract:Thisarticleshowsanexampleofimplementinga4-20mAor0-20mAcurrent-loopoutputusingavoltageoutputdigital-to-analogconverter(DAC)andaVtoIconverter.Current-loopsignals,asopposedtovoltagesignals,arecommonlyusedinindustrialsystemsbecausetheyaremuchlesssubjecttonoiseandrelativelyindifferenttolinelength(becausethecurrentisunaffectedbylineresistance).ThecircuitofFigure1allowsdigitalselectionbetweenthetwostanda……
  • 所需E币: 4
    时间: 2019-12-24 20:01
    大小: 103.67KB
    上传者: 微风DS
    摘要:要了解如何创建,然后抑制共模信号,你首先应该了解在普通电缆配置盾牌和理由的互动。下面的讨论中定义了一个共模信号,回顾了常见的电缆配置,考虑屏蔽与非屏蔽电缆,并介绍了典型的接地措施。文章论述了创建和拒绝,使共模信号的方法。Maxim/Dallas>AppNotes>AMPLIFIERANDCOMPARATORCIRCUITSAUDIOCIRCUITSCOMMUNICATIONSCIRCUITSINTERFACECIRCUITSVIDEOCIRCUITSKeywords:common-modesignals,network,transmissionlines,shieldedcables,unshieldedcables,RS-485,May21,2003RS485,RS-422,RS422,APPLICATIONNOTE2045UnderstandingCommon-ModeSignalsAbstract:Tounderstandhowcommon-modesignalsarecreatedandthensuppressed,youshouldfirstunderstandtheinteractionofshieldsandgroundsincommoncableconfigurations.Thefollowingdiscussiondefinesacommon-modesignal,reviewsthecommoncableconfigurations,considersshieldedvs.unshieldedcables,anddescribestypicalgroundingpractices.Thearticlediscussesmethodswherebycommon-modesignalsarecreatedandrejected.Theprimaryfocus……
  • 所需E币: 4
    时间: 2019-12-24 18:23
    大小: 103.67KB
    上传者: 978461154_qq
    摘要:要了解如何创建,然后抑制共模信号,你首先应该了解在普通电缆配置盾牌和理由的互动。下面的讨论中定义了一个共模信号,回顾了常见的电缆配置,考虑屏蔽与非屏蔽电缆,并介绍了典型的接地措施。文章论述了创建和拒绝,使共模信号的方法。Maxim/Dallas>AppNotes>AMPLIFIERANDCOMPARATORCIRCUITSAUDIOCIRCUITSCOMMUNICATIONSCIRCUITSINTERFACECIRCUITSVIDEOCIRCUITSKeywords:common-modesignals,network,transmissionlines,shieldedcables,unshieldedcables,RS-485,May21,2003RS485,RS-422,RS422,APPLICATIONNOTE2045UnderstandingCommon-ModeSignalsAbstract:Tounderstandhowcommon-modesignalsarecreatedandthensuppressed,youshouldfirstunderstandtheinteractionofshieldsandgroundsincommoncableconfigurations.Thefollowingdiscussiondefinesacommon-modesignal,reviewsthecommoncableconfigurations,considersshieldedvs.unshieldedcables,anddescribestypicalgroundingpractices.Thearticlediscussesmethodswherebycommon-modesignalsarecreatedandrejected.Theprimaryfocus……
  • 所需E币: 4
    时间: 2020-1-9 15:32
    大小: 894.96KB
    上传者: quw431979_163.com
    terrestrialtransmission清華DMB-地面数字电视传输技术TerrestrialDigitalTelevisionBroadcastingTransmissionTechnology白皮书清华大学数字电视传输技术研发中心2004年8月前言在经历了机械电视时代、黑白电子电视和彩色电视时代以后,电视正向着高清晰度电视和数字化方向前进,模拟电视在全世界范围内正在逐步引退。经过多年坚持不懈的研究和发展,地面数字电视广播取得了很多的成果,世界上已经提出了三个地面数字电视广播标准:欧洲的DVB-T、美国的ATSC和日本的ISDB-T,许多国家和地区都在选择和制定自己的地面数字电视广播标准。但随着技术的发展和研究的不断深入,人们在移动接收、频谱效率、单频网、干扰、系统的灵活性等方面有了更深刻的认识和理解。在此背景下,清华大学提出了一种新颖的、适合我国国情的地面数字电视方案,和美国、欧洲的地面标准相对应,称为地面数字多媒体电视广播(DMB-T:TerrestrialDigitalMultimedia/TVBroadcasting)协议。DMB-T的核心采用了mQAM/QPSK的时域同步正交频分复用(TDS-OFDM:TimeDomainSynchronous-OrthogonalFrequencyDivisionMultiplexing)调制技术,使用创新的前向纠错编码技术,并实现了分级调制,支持多媒体业务。本文件针对地面数字电视广播中经常遇到的一些问题,选择了其中100个给出了回答,旨在说明地面数字电视广播国内外各个标准和方案中涉及的技术和应用,以便更好地理解清华DMB-T协议。关于技术咨询如果有什么疑问惑着需要探讨的地方,请与我们及时联系。联系方式如下:清华大学数字电视传输技术研发中心地址:北京市海淀区清……
  • 所需E币: 4
    时间: 2020-1-13 15:03
    大小: 613.85KB
    上传者: 16245458_qq.com
    TransmissionLine……
  • 所需E币: 3
    时间: 2020-1-13 19:34
    大小: 807.44KB
    上传者: givh79_163.com
    TransmissionLineResonatorsChapter6TransmissionLineResonatorsOutlinePrototypeseriesandparallelresonantcircuits-Nearresonance,amicrowaveresonatorcanbemodeledbyAseriesRLClumped-elementequivalentcircuit,or,AparallelRLClumped-elementequivalentcircuit.Transmissionlineresonators-Resonatorscomposedofhalf-orquarter-wavelengthtransmissionline.SeriesandparallelresonantcircuitsSeriesResonantCircuit(resonance)TheinputimpedanceofaseriesresonantcircuitisThecomplexpowerdeliveredtotheresonatorisSeriesandparallelresonantcircuitsThepowerdissipatedbytheresistorisTheaveragemagneticenergystoredintheinductorisTheaverageelectricenergystoredinthecapacitoriswhereVcisthevoltageacrossthecapacitor.Thein……
  • 所需E币: 3
    时间: 2020-1-13 19:40
    大小: 2.57MB
    上传者: quw431979_163.com
    TransmissionLineandWaveguidesChapter3TransmissionLineandWaveguidesOutlineGeneralSolutionsforTEM,TE,andTMWavesParallelWaveguideRectangularWaveguideCoaxialLineSurfacewaveondielectricslabPlanarTransmissionandWaveguideStriplineMicrostriplineCoplanarWaveguideSlotlineIntroductionMicrowavesystemsreliedonwaveguideandcoaxiallinesWaveguidehastheadvantageofhighpower-handlingcapabilityandlowlossbutisbulkyandexpensive.Coaxiallinehasveryhighbandwidthandisconvenientfortestapplications,butisadifficultmediuminwhichtofabricatecomplexmicrowavecomponents.Planartransmissionlinesprovideanalternativeapproach.Stripline,microstrip,slotline,coplanarwaveguide…etc.Compact,lowincost,andeasytointegratewithactivedev……
  • 所需E币: 4
    时间: 2020-1-14 09:33
    大小: 74.59KB
    上传者: givh79_163.com
    SqueezingaTransmissionLineSqueezingaTransmissionLineWhileMaintainingitsLengthYoucanmodifyanexistingtransmissionlinetosqueezeitintoasmallerspace,specifyingseveralcharacteristicsintheprocess,suchascornertype,leadlengthandminimumspacing.Youcanadjustanyorallofthefollowingcharacteristicsasneeded:CornerType--SelectfromMitered,Square,CurveEndingDirection--Thedirection(clockwiseorcounterclockwise)inwhichthelasttwosegmentsconnectedtotheendingleadaredrawnMinimumSpacing--TheminimumspacingbetweentheparalleltracesegmentsMiteredCornerCutoffRatio(%)--ThedesiredcutoffratioforthecornertypeMiteredCurveRadius--ThedesiredcurveradiusforthecornertypeCurveLeadLength--ThelengthofthestartingandendingsegmentsTosqueezeatr……
  • 所需E币: 4
    时间: 2020-1-14 10:25
    大小: 338.9KB
    上传者: 16245458_qq.com
    对共形微带天线有兴趣的朋友请进,DesignofNonplanarMicrostripAntennasandTransmissionLines……
  • 所需E币: 3
    时间: 2020-1-14 10:39
    大小: 145.17KB
    上传者: 二不过三
    TransmissionZerosinFilterDesignTransmissionZerosinFilterDesignByRandallW.RheaEaglewareCorporationoreeconomicandeffectivebandpassfilterscanbedesignedbycontrollingthelocationoftransmissionzeros.Whatdowemeanbytransmissionzeros?Considerthefifth-orderlowpassfilterinFigure1(a).Thereislittleattenuationatlowfrequenciesandincreasingattenuationabovethecutoff.Onlyatinfinitefrequencyistherenotransmission.Infact,atinfinitefrequency,eachinductorbecomesanopenandeachcapacitorbecomesashort.Thisfilterhasfivetransmissionzeros(TZs)atinfinitefrequency.ThefifthorderhighpassfilterinFigure1(b)hasfiveTZsatDC.Itisessentialthattheinductorsandcapacitorsalternate.Ifweweretoattempttobuildafifth-orderlowpasswithfiveseriesinducto……
  • 所需E币: 5
    时间: 2020-1-14 11:13
    大小: 3.08MB
    上传者: 微风DS
    RF大牛ClaytonR.Paul经典著作‘Analys...,AnalysisofMulticonductorTransmissionLines……
  • 所需E币: 3
    时间: 2020-1-14 11:37
    大小: 1.3MB
    上传者: quw431979_163.com
    TransmissionDesignHandbook,Transmission_Line_Design_Handbook……
  • 所需E币: 4
    时间: 2020-1-15 11:34
    大小: 159.87KB
    上传者: quw431979_163.com
    HighSpeedTransmissionHighSpeedTransmissionwithLVDSLinkDevicesHighSpeedTransmissionwithLVDSLinkDevicesHighspeeddatatransmissionrequiresadesignertobeawareoffactorswhichmayimpactthecorrectsamplingofdata.Inparticular,itemssuchasexcessiveskewandjittercanleadtodatasamplingerrors,limitingthemaximumbandwidthperformanceoftheLVDSLink.ThefollowingisadiscussionofLVDSLinkreceiverdatasampling,skewandjittermargin,andanexplanationofskewandjittercomponents.LVDSLINKDATASAMPLINGTheadvantageofusingtheLVDSLinkdevices(FPDLinkandChannelLink)istheabilitytoconvertmanyparalleldatalinesintoanarrowerserializedinterface.ThisserializedLVDSinterfaceiscapableofrunningatseventimesthedatarateoftheparallelTTLinterfa……