leslie
leslie
39#
字体大小:
t
T
发表于 2011-04-04 12:56
只看楼主
FMTUNER 最新排名：THE SHOOTOUT IS OVER!! Rankings after Shootout #81: 1 PLUS: -C- Accuphase T-109V - Very natural sound, good bass. Pinpoint imaging. Lifelike, three-dimensional sound, smooth extended highs. 1 (TIE): -C- Kenwood L-02T - Most natural sound, good bass. Pinpoint imaging. Lifelike, three-dimensional sound. 1 (TIE): -C- Burmester 978 - Natural, open and airy sound, good bass. Pinpoint imaging. Lifelike, three-dimensional sound with nice extended highs. 4: -C- Sansui TU-919 - The prince who could be king. 5: -C- Sansui TU-X1 - Very good sound top to bottom. Big soundstage, three-dimensional. Very slight diffuse sound. 6: -C- Audiolab 8000T - Good bass, natural but diffuse sound, sweet extended highs. 7: -C- Philips AH6731 - A very natural, neutral sound. Stereo separation best with a good signal. 8: -C- Revox B760 - Great bass, lifelike midrange and extended highs. 9: -M- Mitsubishi DA-F20 - Quick, punchy bass, open, lively midrange and extended highs. 10: -M- Kenwood KT-5020 - Great bass and midrange and extended, sweet treble. Again, why pay more? 11: -M- Kenwood KT-990D - Smooth, clean sound that always pleased. Why pay more? 12: -M- Meridian Model 104 - Excellent, natural sound, good bass, no to DX games. 13: -M- Meridian Model 504 - Good bass, excellent midrange with smooth, just-right highs. 14: -M- Kenwood L-1000T - Good bass, punchy midrange, sweet extended highs. 15: -M- Sansui TU-X701 - Great-sounding midrange, bass OK, softer highs next to the L-02T. 16: -M- Luxman T-117 - Very good-sounding tuner. No real faults, top to bottom. Not as three-dimensional as the L-02T and gives up some bass richness. 17: -M- Sansui TU-717 - Good bass and midrange with nice "depth" to the soundstage. More forward than the L-02T. 18: -M- B&K TS-108 - Very nice midrange, good bass and nice, extended highs. 19: -M- Technics ST-9038 - Very good bass, nice midrange, smooth treble. 20: -M- Magnum Dynalab MD-108 - Bass OK, very good imaging and realistic midrange, extended but forward highs. 21: -M- Kenwood KT-917 - Good bass, midrange and treble. A very pleasant sound but more one-dimensional when placed next to the L-02T. 22: -M- Sansui TU-S9 - Smooth, natural sound. A budget bargain. 23: -M- Kenwood KT-1100 - Quite tuneful, but flatter soundstage than the L-02T. 24: -M- McIntosh MR 80 - Good bass, lively midrange and pleasant highs. More one-dimensional than the L-02T. 25: -M- Sanyo Plus T35 - Good bass, laidback midrange and extended, pleasant highs. 26: -M- Technics ST-G7 - Very nice bass, articulate midrange, forward but nice upper range. 27: -M- Pioneer F-99X - Follows behind the big bass dogs but the midrange and treble are where it's at. Sweet, clean, quiet and to be copied. 28: -M- Kenwood KT-3300D - Very good bass, slightly diffuse light mids and pleasant extended highs. A laidback, nice listen. 29: -M- Pioneer F-90 - Great sonics with a slightly lighter sonic presentation than the top dogs. Upper midrange and treble are top-notch. 30: -M- Sansui TU-D99X - Good bass. Bass, midrange and treble work well together for a balanced sound. 31: -M- Hitachi FT-007 - Clean, balanced sound, but less dynamic than the L-02T. 32: -M- Sony ST-J88B - Good bass, pleasing midrange, slightly forward and sweet treble. 33: -M- Linn Kremlin - OK bass; articulate, precise sound; good high frequency. Midrange, bass loses some natural warmth. 34: -M- Restek Metric - Excellent imaging, bass and highs. Midrange gave up some to other tuners. 35: -M- Onix TU39 - Dynamic, smooth, the midrange give up some "life" to others. Some added sparkle in the highs. 36: -M- Perreaux TU-3 - Nice balanced sound. Gives up some richness and dynamics to the L-02T. 37: -M- Magnum Dynalab FT-101 - Good all-around sound, treble very slightly forward. 38: -M- Kenwood L-07TII - Good all-around sound but loses some inner detail. 39: -M- Accuphase T-109 - Great bass, dry midrange, pleasant but slightly forward treble. 40: -M- Magnum Dynalab FT-101A Etude - A good, balanced sound, but slightly dry. 41: -M- Technics ST-8077 - Good bass, midrange OK. Nice treble presentation. 42: -M- Technics ST-8080 - Good bass, good midrange, forward highs but not unpleasant. 43: -M- Nikko Gamma V - Very good bass, good imaging, treble forward but not unpleasant. 44: -M- Kenwood KT-8300 - Good bass and dynamics, with a slightly forward upper midrange and treble. 45: -M- Onkyo T-4500 - Slightly lighter but a pleasing sound. Neutral, top to bottom, with nice highs. 46: -M- Onkyo T-9090II - Pleasant sound, good bass, but not as dynamic as some tuners. Great DX machine. 47: -M- NAD 4155 - Good, punchy bass. Light, articulate mids with well-mated highs. 48: -M- Pioneer F-91 - Very good bass punch and control, articulate midrange with forward highs. May be a good tuner for a large room. 49: -M- Pioneer TX-9800 - Rich bass presentation. Good midrange with a treble slightly forward that took away from the total picture. 50: -M- Tandberg 3011A - Good bass, midrange a little light, sweet treble. Very good imaging. 51: -M- Sansui TU-417 - A most pleasant sound, bottom to top. Needs good signals. 52: -M- Carver TX-11b - Punchy bass, clean highs and treble. 53: -M- Sumo Charlie - Punchy bass, good midrange, slightly rolled-off treble. 54: -M- Revox B260 - Rich bass and lower midrange. Good imaging. Three-dimensional. The highs are a little too much for my personal taste. The high rating reflects its other positive sound qualities. 55: -M- Yamaha CT-7000 - Warm-sounding bass, pleasant midrange and highs. Highs a little rolled-off. 56: -M- Sequerra Model 1 - Harmonically rich bass and lower midrange. Very seductive, but if you want accuracy, shop elsewhere. 57: -M- Magnum Dynalab FT-11 "NEW" - Good sound, natural midrange, treble nice, loose bass. 58: -M- Kenwood KT-7300 - Punchy bass, pleasant mids and highs. Slight loss of ambience. 59: -M- Onkyo T-4310R - Pleasant, inoffensive sound, good imaging. Good digital DXing tuner. 60: -M- Magnum Dynalab FT-101A - Pleasant light, airy sound. Lacks bass dynamics. 61: -M- Realistic TM-1001 - Sweet treble, pleasant mids, but the bass is not as full and dynamic as the big dogs. 62: -M- Yamaha T-2 - Very pleasant and listenable. This may be the cutoff tuner between the keepers and the also-rans. 63: Revox B261 - Punchy bass, pleasant enough but slightly forward mids and highs. 64: Pioneer TX-9500II - Clean, articulate sound. Lighter sonic presentation against the L-02T. 65: SAE Mark VI - Inoffensive sound, good background music. A mini-Sequerra. 66: Denon TU-850 - Good sound, midrange just right, treble sweet, slightly bass-shy. 67: Sansui TU-217 - Good sound when reception is strong. 68: Kenwood L-01T - Good sound, midrange slightly forward, good bass. 69: Phase Linear Model 5000 Series Two - Bass-shy, pleasant midrange and treble. 70: Magnum Dynalab FT-11 "OLD" - Good bass, dry midrange, treble OK. 71: Quad FM4 - Very nice midrange, good resolution, extended treble, rolled off bass. 72: Technics ST-9030 - Inoffensive but bland. 73: Naim NAT 01 - Bass OK, midrange OK, treble sweet. 74: Luxman T-115 - Good bass, midrange OK, treble slightly forward. 75: Nakamichi ST-7 - Muffled bass, forward midrange, highs soft and inoffensive. 76: Marantz 2130 - OK bass, midrange and treble forward and "light" sounding. 77: McIntosh MR 78 - Good bass, slightly electronic sound. 78: Fanfare FT-1A - Best through the low-output jacks, clean but bright midrange, lacks bass power. 79: Kenwood KT-7500 - Flat soundstage, better sound can be found. One-note bass. More boring than unpleasant in a long listening session. 80: Cambridge Audio T500 - Bass light, midrange forward and lacks focus, highs OK. 81: Kyocera T-910 - Pleasant sound, but what's that ringing in my ears? 82: SAE 8000 - Not irritating but not involving, either. Too much background noise. 83: Kenwood KT-815 - Bass thin, treble forward. It cries out for a new audio stage. 84: Denon TU-600 - Good sound, but not recommended because of reception problems

我们听收音机在调台时会听到沙沙的声音中波也好短波也好电视在收台时也好都有听别人说这是电流声书上也这么说在下请教直流电也会有电流声吗沙沙的声音也不是一成不变的也会有小的规律...
我们听收音机在调台时会听到沙沙的声音
中波也好短波也好 电视在收台时也好都有
听别人说这是电流声
书上也这么说在下请教
直流电也会有电流声吗
沙沙的声音也不是一成不变的
也会有小的规律变化的 那这声音是如何产生的呢
高分求答案
希望真正知道的给予解答不要 不知道乱说
本人好奇
满意的在加悬赏100
展开
展开全部这个问题牵涉到信号处理，具体可以参见通信原理和信号处理相关书籍。如果通俗一点来说，收音机的信号接受包含以下几个步骤：1、电台将声音进行调制，成为适合传输的频率。2、调制好的信号进行传输(用到什么载波啊，载频啊之类的，不必深究)3、收音机收到信号并解调那么所谓电流，沙沙声，无非是3种原因，而三种原因均是干扰。1.在调制过程中，引入了杂波，在声源处直接有了问题。2.在传输的过程中，遇到了干扰（简单想想，比如环境天然产生的电磁波，或者是别的电台的相近频率，或者传输过程中遇到了高压电线之类的东西导致干扰）。这些干扰进入了收音机中，收音机是无法分辨它们是不是杂音的，所以就被“原封不动”的解调了出来（当然，不是说解调出来的声音完全和杂音一样，就是杂音解调出来也是杂音而已）3.解调过程中引入了杂波，大多数是因为设备老化等等。日常生活中收音机产生的杂音沙沙声大多数都是在传输过程中遇到干扰。并且传输的距离越远，或者传输难度越大，就会导致“声源”的信号变弱，但是杂波是一直都有的，声源信号越弱，杂波影响产生的负面效果就越强烈，别如沙沙声。还有就是解调器（收音机）设备老化，听到的电流声大多数因为如此。已赞过已踩过你对这个回答的评价是？评论
收起',getTip:function(t,e){return t.renderTip(e.getAttribute(t.triangularSign),e.getAttribute("jubao"))},getILeft:function(t,e){return t.left+e.offsetWidth/2-e.tip.offsetWidth/2},getSHtml:function(t,e,n){return t.tpl.replace(/\{\{#href\}\}/g,e).replace(/\{\{#jubao\}\}/g,n)}},baobiao:{triangularSign:"data-baobiao",tpl:'{{#baobiao_text}}',getTip:function(t,e){return t.renderTip(e.getAttribute(t.triangularSign))},getILeft:function(t,e){return t.left-21},getSHtml:function(t,e,n){return t.tpl.replace(/\{\{#baobiao_text\}\}/g,e)}}};function l(t){return this.type=t.type
"defaultTip",this.objTip=u[this.type],this.containerId="c-tips-container",this.advertContainerClass=t.adSelector,this.triangularSign=this.objTip.triangularSign,this.delaySeconds=200,this.adventContainer="",this.triangulars=[],this.motherContainer=a("div"),this.oTipContainer=i(this.containerId),this.tip="",this.tpl=this.objTip.tpl,this.init()}l.prototype={constructor:l,arrInit:function(){for(var t=0;t0}});else{var t=window.document;n.prototype.THROTTLE_TIMEOUT=100,n.prototype.POLL_INTERVAL=null,n.prototype.USE_MUTATION_OBSERVER=!0,n.prototype.observe=function(t){if(!this._observationTargets.some((function(e){return e.element==t}))){if(!t
1!=t.nodeType)throw new Error("target must be an Element");this._registerInstance(),this._observationTargets.push({element:t,entry:null}),this._monitorIntersections(),this._checkForIntersections()}},n.prototype.unobserve=function(t){this._observationTargets=this._observationTargets.filter((function(e){return e.element!=t})),this._observationTargets.length
(this._unmonitorIntersections(),this._unregisterInstance())},n.prototype.disconnect=function(){this._observationTargets=[],this._unmonitorIntersections(),this._unregisterInstance()},n.prototype.takeRecords=function(){var t=this._queuedEntries.slice();return this._queuedEntries=[],t},n.prototype._initThresholds=function(t){var e=t
[0];return Array.isArray(e)
(e=[e]),e.sort().filter((function(t,e,n){if("number"!=typeof t
isNaN(t)
t1)throw new Error("threshold must be a number between 0 and 1 inclusively");return t!==n[e-1]}))},n.prototype._parseRootMargin=function(t){var e=(t
"0px").split(/\s+/).map((function(t){var e=/^(-?\d*\.?\d+)(px|%)$/.exec(t);if(!e)throw new Error("rootMargin must be specified in pixels or percent");return{value:parseFloat(e[1]),unit:e[2]}}));return e[1]=e[1]
e[0],e[2]=e[2]
e[0],e[3]=e[3]
e[1],e},n.prototype._monitorIntersections=function(){this._monitoringIntersections
(this._monitoringIntersections=!0,this.POLL_INTERVAL?this._monitoringInterval=setInterval(this._checkForIntersections,this.POLL_INTERVAL):(r(window,"resize",this._checkForIntersections,!0),r(t,"scroll",this._checkForIntersections,!0),this.USE_MUTATION_OBSERVER&&"MutationObserver"in window&&(this._domObserver=new MutationObserver(this._checkForIntersections),this._domObserver.observe(t,{attributes:!0,childList:!0,characterData:!0,subtree:!0}))))},n.prototype._unmonitorIntersections=function(){this._monitoringIntersections&&(this._monitoringIntersections=!1,clearInterval(this._monitoringInterval),this._monitoringInterval=null,i(window,"resize",this._checkForIntersections,!0),i(t,"scroll",this._checkForIntersections,!0),this._domObserver&&(this._domObserver.disconnect(),this._domObserver=null))},n.prototype._checkForIntersections=function(){var t=this._rootIsInDom(),n=t?this._getRootRect():{top:0,bottom:0,left:0,right:0,width:0,height:0};this._observationTargets.forEach((function(r){var i=r.element,a=o(i),c=this._rootContainsTarget(i),s=r.entry,u=t&&c&&this._computeTargetAndRootIntersection(i,n),l=r.entry=new e({time:window.performance&&performance.now&&performance.now(),target:i,boundingClientRect:a,rootBounds:n,intersectionRect:u});s?t&&c?this._hasCrossedThreshold(s,l)&&this._queuedEntries.push(l):s&&s.isIntersecting&&this._queuedEntries.push(l):this._queuedEntries.push(l)}),this),this._queuedEntries.length&&this._callback(this.takeRecords(),this)},n.prototype._computeTargetAndRootIntersection=function(e,n){if("none"!=window.getComputedStyle(e).display){for(var r,i,a,s,u,l,f,h,p=o(e),d=c(e),v=!1;!v;){var g=null,m=1==d.nodeType?window.getComputedStyle(d):{};if("none"==m.display)return;if(d==this.root
d==t?(v=!0,g=n):d!=t.body&&d!=t.documentElement&&"visible"!=m.overflow&&(g=o(d)),g&&(r=g,i=p,a=void 0,s=void 0,u=void 0,l=void 0,f=void 0,h=void 0,a=Math.max(r.top,i.top),s=Math.min(r.bottom,i.bottom),u=Math.max(r.left,i.left),l=Math.min(r.right,i.right),h=s-a,!(p=(f=l-u)>=0&&h>=0&&{top:a,bottom:s,left:u,right:l,width:f,height:h})))break;d=c(d)}return p}},n.prototype._getRootRect=function(){var e;if(this.root)e=o(this.root);else{var n=t.documentElement,r=t.body;e={top:0,left:0,right:n.clientWidth
r.clientWidth,width:n.clientWidth
r.clientWidth,bottom:n.clientHeight
r.clientHeight,height:n.clientHeight
r.clientHeight}}return this._expandRectByRootMargin(e)},n.prototype._expandRectByRootMargin=function(t){var e=this._rootMarginValues.map((function(e,n){return"px"==e.unit?e.value:e.value*(n%2?t.width:t.height)/100})),n={top:t.top-e[0],right:t.right+e[1],bottom:t.bottom+e[2],left:t.left-e[3]};return n.width=n.right-n.left,n.height=n.bottom-n.top,n},n.prototype._hasCrossedThreshold=function(t,e){var n=t&&t.isIntersecting?t.intersectionRatio
0:-1,r=e.isIntersecting?e.intersectionRatio
0:-1;if(n!==r)for(var i=0;i0&&function(t,e,n,r){var i=document.getElementsByClassName(t);if(i.length>0)for(var o=0;o展开全部。。。就是宇宙射线好不好。还电流呢。 如果通过屏蔽，收音机调任何波段都不会有噪音的。 可以参照Dsc的关于宇宙形成的纪录片，里面明确说明大爆炸后，什么脉冲星什么的产生的射线就是导致电视雪花的原因。对收音机也是一样的。展开全部实验一　器材用一节干电池　一根导线　收音机;步骤打开收音机调节至无声（空闲）频道　将导线接在电池一端，用导线另一端在电池另一端不断接通和断开(在收音机旁）；现象听见收音机中有和通断电流一样的沙沙声；结论电流的通断能产生电磁波干扰收音机的正常收音，所从任何电流通断都会干扰收音机的收音
展开全部既然你说中波，短波都没有，那么只剩下调频电波了，“电流声”这个名词在教科书里面是没有的，这是网络语言，纯正的直流电是没有任何杂音的，比如：你把一节干电池和喇叭连接，能听到任何声音吗？当然，如果是交流收音机的整流滤波电路故障，则会产生50HZ的交流声，　你说的沙沙的声音可能是在收听调频波段小信号电台或距离电台较远时产生的，这是调频波特有的声音，当然，也不是所有的电台都有噪音的，信号强到一定程度就会将噪声抑制，只剩下优美的音乐了，调频波占用无线电频带较宽，信号保真度最好，是目前高质量广播的最好的调制方式。展开全部有别的电磁波干扰,附近要是有人打手机沙沙声会更明显
收起
1条折叠回答
收起
更多回答（3）
推荐律师服务：
若未解决您的问题，请您详细描述您的问题，通过百度律临进行免费专业咨询
为你推荐：
下载百度知道APP，抢鲜体验使用百度知道APP，立即抢鲜体验。你的手机镜头里或许有别人想知道的答案。扫描二维码下载
×个人、企业类侵权投诉
违法有害信息,请在下方选择后提交
类别色情低俗
涉嫌违法犯罪
时政信息不实
垃圾广告
低质灌水
我们会通过消息、邮箱等方式尽快将举报结果通知您。说明
做任务开宝箱累计完成0
个任务
10任务
50任务
100任务
200任务
任务列表加载中...

选择擅长的领域继续答题？
{@each tagList as item}
${item.tagName}
{@/each}
手机回答更方便，互动更有趣，下载APP
提交成功是否继续回答问题？
手机回答更方便，互动更有趣，下载APP
展开全部收音机能不能收台，首先取决你所在位置是否有电台信号。特别是调频广播，无线传输距离只有几十公里，所一些地方无信号处于盲区收不到台就很正常。已赞过已踩过你对这个回答的评价是？评论
收起
展开全部停振了，检查本振电路吧。只要起振就一定能收到电台声音。展开全部只能说明低放级是好的。感应高频第一级基极，有没有信号噪音，有的话，是磁棒和可变电容器线路问题，没有，查中放级。
本回答被网友采纳
展开全部5V充电宝用不上收音机的电源吗
收起
1条折叠回答
收起
更多回答（2）
推荐律师服务：
若未解决您的问题，请您详细描述您的问题，通过百度律临进行免费专业咨询
为你推荐：
下载百度知道APP，抢鲜体验使用百度知道APP，立即抢鲜体验。你的手机镜头里或许有别人想知道的答案。扫描二维码下载
×个人、企业类侵权投诉
违法有害信息,请在下方选择后提交
类别色情低俗
涉嫌违法犯罪
时政信息不实
垃圾广告
低质灌水
我们会通过消息、邮箱等方式尽快将举报结果通知您。说明
做任务开宝箱累计完成0
个任务
10任务
50任务
100任务
200任务
任务列表加载中...