http://jendo.synology.me/wiki1231/index.php?action=history&feed=atom&title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C 2026-04-10T05:33:00Z 本 Wiki 上此頁面的修訂歷史 MediaWiki 1.35.14 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27577&oldid=prev 2017-01-03T03:36:59Z

<p><span dir="auto"><span class="autocomment">(三)電阻濾除直流分量</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 03:36 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l60" >第60行：</td> <td colspan="2" class="diff-lineno">第60行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#<del class="diffchange diffchange-inline">直流分量：檢波電路輸出訊號的平均幅值大小，檢波電路輸出訊號幅度大，其平均值大，這一直流電壓值就大，反之則小。這一直流成分在收音機電路中用來控制一種稱為中頻放大器的放大倍數</del>(也可以稱為增益)，稱為AGC(自動增益控制)<del class="diffchange diffchange-inline">電壓。AGC電壓被檢波電路輸出端耦合電容隔離，不能與音頻訊號一起加到後面放大電路中，而是專門加到AGC電路中。透過接地的電阻，訊號的各點電壓幅值均減去平均幅值，音頻訊號向下平移，修正掉原始訊號電壓因為去掉下包絡導致的向上偏移。</del></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#<ins class="diffchange diffchange-inline">直流分量：檢波電路輸出訊號的平均幅值大小，檢波電路輸出訊號幅度大，其平均值大，這一直流電壓值就大，反之則小。透過接地的電阻，訊號的各點電壓幅值均減去平均幅值，音頻訊號向下平移，修正掉原始訊號電壓因為去掉下包絡導致的向上偏移。&lt;br/&gt;直流成分在收音機電路中用來控制一種稱為中頻放大器的放大倍數</ins>(也可以稱為增益)，稱為AGC(自動增益控制)<ins class="diffchange diffchange-inline">電壓。AGC電壓被檢波電路輸出端「耦合電容」隔離，不能與音頻訊號一起送到後面放大電路中，而是專門加到AGC電路中。</ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#檢波電路輸出訊號中還有高頻載波訊號，這一訊號無用，在通過高頻濾波電容時，被濾到接地端。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#檢波電路輸出訊號中還有高頻載波訊號，這一訊號無用，在通過高頻濾波電容時，被濾到接地端。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <!-- diff cache key wiki1231:diff::1.12:old-27576:rev-27577 --> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27576&oldid=prev 2017-01-03T03:32:36Z

<p><span dir="auto"><span class="autocomment">(三)電阻濾除直流分量</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 03:32 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l57" >第57行：</td> <td colspan="2" class="diff-lineno">第57行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(三)電阻濾除直流分量====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(三)電阻濾除直流分量====</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://<del class="diffchange diffchange-inline">wenda</del>.<del class="diffchange diffchange-inline">chinabaike.com/uploads</del>/<del class="diffchange diffchange-inline">allimg</del>/<del class="diffchange diffchange-inline">131029</del>/<del class="diffchange diffchange-inline">1425524238-2</del>.jpg&#039; width=&#039;228&#039; height=* /&gt;&lt;/div&gt;</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://<ins class="diffchange diffchange-inline">jendo</ins>.<ins class="diffchange diffchange-inline">org</ins>/<ins class="diffchange diffchange-inline">files</ins>/<ins class="diffchange diffchange-inline">study</ins>/<ins class="diffchange diffchange-inline">調幅波的三種成分</ins>.jpg&#039; width=&#039;228&#039; height=* /&gt;&lt;/div&gt;</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27558&oldid=prev 2017-01-03T00:47:56Z

<p><span dir="auto"><span class="autocomment">電晶體電壓訊號放大原理</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 00:47 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l118" >第118行：</td> <td colspan="2" class="diff-lineno">第118行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;/tr&gt;&lt;/table&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;/tr&gt;&lt;/table&gt;</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>首先我們先利用輸入電壓e和偏壓電壓E&lt;sub&gt;1&lt;/sub&gt;產生基極－射極間電壓(V&lt;sub&gt;BE&lt;/sub&gt;)，並且讓與前述電壓(V&lt;sub&gt;BE&lt;/sub&gt;)呈等比例的電流(I&lt;sub&gt;B&lt;/sub&gt;)，也就是h&lt;sub&gt;FE&lt;/sub&gt;(<del class="diffchange diffchange-inline">註1</del>)倍的電流(I&lt;sub&gt;C&lt;/sub&gt;)通過集極，當集極電流(I&lt;sub&gt;C&lt;/sub&gt;)通過電阻R&lt;sub&gt;L&lt;/sub&gt;後，電壓I&lt;sub&gt;C&lt;/sub&gt; × R&lt;sub&gt;L&lt;/sub&gt;就會出現在電阻R&lt;sub&gt;L&lt;/sub&gt;的兩端。所以，輸入電壓e就會被轉換(放大)為電壓I&lt;sub&gt;C&lt;/sub&gt;R&lt;sub&gt;L&lt;/sub&gt;，並產生輸出。</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>首先我們先利用輸入電壓e和偏壓電壓E&lt;sub&gt;1&lt;/sub&gt;產生基極－射極間電壓(V&lt;sub&gt;BE&lt;/sub&gt;)，並且讓與前述電壓(V&lt;sub&gt;BE&lt;/sub&gt;)呈等比例的電流(I&lt;sub&gt;B&lt;/sub&gt;)，也就是h&lt;sub&gt;FE&lt;/sub&gt;(<ins class="diffchange diffchange-inline">註</ins>)倍的電流(I&lt;sub&gt;C&lt;/sub&gt;)通過集極，當集極電流(I&lt;sub&gt;C&lt;/sub&gt;)通過電阻R&lt;sub&gt;L&lt;/sub&gt;後，電壓I&lt;sub&gt;C&lt;/sub&gt; × R&lt;sub&gt;L&lt;/sub&gt;就會出現在電阻R&lt;sub&gt;L&lt;/sub&gt;的兩端。所以，輸入電壓e就會被轉換(放大)為電壓I&lt;sub&gt;C&lt;/sub&gt;R&lt;sub&gt;L&lt;/sub&gt;，並產生輸出。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">※註1：h</del>&lt;sub&gt;FE&lt;/sub&gt;，電晶體的直流電流放大率</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">※註：h</ins>&lt;sub&gt;FE&lt;/sub&gt;，電晶體的直流電流放大率</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===NPN電晶體電流圖示===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===NPN電晶體電流圖示===</div></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27557&oldid=prev 2017-01-03T00:44:59Z

<p><span dir="auto"><span class="autocomment">(二)電容濾除載波</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 00:44 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l52" >第52行：</td> <td colspan="2" class="diff-lineno">第52行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#對於高頻載波而言，其頻率很高，電容對它的容抗很小而呈通路狀態，檢波電路輸出端的高頻載波訊號被電容從旁路引到地線，起到高頻濾波的作用。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#對於高頻載波而言，其頻率很高，電容對它的容抗很小而呈通路狀態，檢波電路輸出端的高頻載波訊號被電容從旁路引到地線，起到高頻濾波的作用。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#對於音頻訊號而言，由於高頻濾波電容的容量很小，它對音頻訊號的容抗很大，相當於斷路，所以音頻訊號不能被電容從旁路引到地線。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#對於音頻訊號而言，由於高頻濾波電容的容量很小，它對音頻訊號的容抗很大，相當於斷路，所以音頻訊號不能被電容從旁路引到地線。</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#<del class="diffchange diffchange-inline">對於直流電壓而言，電容的隔直特性使電容相當於斷路，所以檢波電路輸出端的直流電壓不能被被電容從旁路引到地線。 </del></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#<ins class="diffchange diffchange-inline">對於直流電壓而言，電容的隔直特性(註)使電容相當於斷路，所以檢波電路輸出端的直流電壓不能被被電容從旁路引到地線。</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">*註，電容隔直通交特性：&lt;br/&gt;如果一個電容接到直流電上時，在接通的瞬間是充電，但一旦穩定後，電路中電荷就不再移動，因而電路中也無電流。當電路發生變化，導致電容兩端電壓減少時，電容就會放電。&lt;br/&gt;因為交流電的電壓不斷發生變化，所以電容就不斷的充放電，因而電流好像可以通過電容器。實際不是通過電容器。&lt;br/&gt;當然電容對交流電也有阻礙作用，頻率越低阻礙就越大，反之越小。</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(三)電阻濾除直流分量====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(三)電阻濾除直流分量====</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://wenda.chinabaike.com/uploads/allimg/131029/1425524238-2.jpg&#039; width=&#039;228&#039; height=* /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://wenda.chinabaike.com/uploads/allimg/131029/1425524238-2.jpg&#039; width=&#039;228&#039; height=* /&gt;&lt;/div&gt;</div></td></tr> </table>

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<p><span dir="auto"><span class="autocomment">(一)二極體整流</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 00:34 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l44" >第44行：</td> <td colspan="2" class="diff-lineno">第44行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">如右圖，調幅訊號在左上，拉開時間軸後表達如右上，通過二極體之後，下半絡全部被截止濾除，只剩上包絡。</del></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">如右圖，調幅訊號在左上，拉開時間軸後表達如右上，通過二極體之後，下包絡全部被截止濾除，只剩上包絡。</ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>上包絡將再送給電容，透過電容的充電、放電過程，修整出包絡的平滑曲線。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>上包絡將再送給電容，透過電容的充電、放電過程，修整出包絡的平滑曲線。</div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(二)電容濾除載波====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(二)電容濾除載波====</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;img src=&#039;http://www.chinabaike.com/uploads/allimg/131114/2253355L6-0.jpg&#039; width=&#039;700&#039; height=* /&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;img src=&#039;http://www.chinabaike.com/uploads/allimg/131114/2253355L6-0.jpg&#039; width=&#039;700&#039; height=* /&gt;</div></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27555&oldid=prev 2017-01-03T00:31:46Z

<p><span dir="auto"><span class="autocomment">二、檢波電路</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月3日 (二) 00:31 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l41" >第41行：</td> <td colspan="2" class="diff-lineno">第41行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電容可以濾除高頻載波，只讓低頻包絡通過。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電容可以濾除高頻載波，只讓低頻包絡通過。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電阻則濾除直流分量，消除捨棄下包絡時對原始訊號的偏移。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電阻則濾除直流分量，消除捨棄下包絡時對原始訊號的偏移。</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">其中濾除下包絡與濾除直流分量連帶，可以同時省略，但用接地的電容濾除高頻載波則無法省略。</ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27554&oldid=prev 2017-01-02T16:24:11Z

<p><span dir="auto"><span class="autocomment">四、連接調諧電路與與放大電路並提供電源</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月2日 (一) 16:24 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l69" >第69行：</td> <td colspan="2" class="diff-lineno">第69行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>將第一個電晶體的輸出再導入第二個電晶體的基極，可將放大的訊號再次放大。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>將第一個電晶體的輸出再導入第二個電晶體的基極，可將放大的訊號再次放大。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>===<del class="diffchange diffchange-inline">四、連接調諧電路與與放大電路並提供電源</del>===</div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>===<ins class="diffchange diffchange-inline">四、連接調諧電路、檢波元件與放大電路並提供電源</ins>===</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;img src=&#039;http://jendo.org/wiki1231/images/thumb/2/2d/收音機電路圖.png/800px-收音機電路圖.png&#039; /&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;img src=&#039;http://jendo.org/wiki1231/images/thumb/2/2d/收音機電路圖.png/800px-收音機電路圖.png&#039; /&gt;</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27553&oldid=prev 2017-01-02T16:22:47Z

<p><span dir="auto"><span class="autocomment">(三)電阻濾除直流分量</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月2日 (一) 16:22 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l56" >第56行：</td> <td colspan="2" class="diff-lineno">第56行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>右圖左邊是剛通過二極體整流的訊號，其中包含三個成分：</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#要還原回來的音頻訊號。</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#直流分量：檢波電路輸出訊號的平均幅值大小，檢波電路輸出訊號幅度大，其平均值大，這一直流電壓值就大，反之則小。這一直流成分在收音機電路中用來控制一種稱為中頻放大器的放大倍數(也可以稱為增益)，稱為AGC(自動增益控制)<del class="diffchange diffchange-inline">電壓。AGC電壓被檢波電路輸出端耦合電容隔離，不能與音頻訊號一起加到後面放大電路中，而是專門加到AGC電路中。透過接地的電阻訊號的各點幅值減去平均幅值，音頻訊號向下平移，修正掉原始訊號電壓因為去掉下包絡導致的向上偏移。</del></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#直流分量：檢波電路輸出訊號的平均幅值大小，檢波電路輸出訊號幅度大，其平均值大，這一直流電壓值就大，反之則小。這一直流成分在收音機電路中用來控制一種稱為中頻放大器的放大倍數(也可以稱為增益)，稱為AGC(自動增益控制)<ins class="diffchange diffchange-inline">電壓。AGC電壓被檢波電路輸出端耦合電容隔離，不能與音頻訊號一起加到後面放大電路中，而是專門加到AGC電路中。透過接地的電阻，訊號的各點電壓幅值均減去平均幅值，音頻訊號向下平移，修正掉原始訊號電壓因為去掉下包絡導致的向上偏移。</ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#檢波電路輸出訊號中還有高頻載波訊號，這一訊號無用，在通過高頻濾波電容時，被濾到接地端。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#檢波電路輸出訊號中還有高頻載波訊號，這一訊號無用，在通過高頻濾波電容時，被濾到接地端。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27552&oldid=prev 2017-01-02T16:18:38Z

<p><span dir="auto"><span class="autocomment">二、檢波電路</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月2日 (一) 16:18 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l37" >第37行：</td> <td colspan="2" class="diff-lineno">第37行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/6/6c/Simple_envelope_detector.svg&#039; /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/6/6c/Simple_envelope_detector.svg&#039; /&gt;&lt;/div&gt;</div></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">如右圖，調幅波訊號由左上方送入，電容與電阻在下方接地。三個元件的作用分別簡述如下：</del></div></td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">如右圖，調幅波訊號由左上方送入，電容與電阻在下方接地。檢波電路三個元件的作用分別簡述如下：</ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#二極體可以整流，濾除下包絡。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#二極體可以整流，濾除下包絡。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電容可以濾除高頻載波，只讓低頻包絡通過。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電容可以濾除高頻載波，只讓低頻包絡通過。</div></td></tr> </table>

丁志仁 http://jendo.synology.me/wiki1231/index.php?title=%E6%94%B6%E9%9F%B3%E6%A9%9F%E7%9A%84%E5%8E%9F%E7%90%86%E8%88%87%E5%AF%A6%E4%BD%9C&diff=27551&oldid=prev 2017-01-02T16:17:42Z

<p><span dir="auto"><span class="autocomment">二、檢波電路</span></span></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="zh-Hant-TW"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">←上個修訂</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">於 2017年1月2日 (一) 16:17 的修訂</td> </tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l29" >第29行：</td> <td colspan="2" class="diff-lineno">第29行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===二、檢波電路===</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>===二、檢波電路===</div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/d/d7/Analytic.svg&#039; width=&#039;180&#039; height=* /&gt;&lt;/div&gt;</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">右圖為從調幅收音機天線收下來的調幅訊號。橫軸為時間，縱軸為振幅。藍色為載波；紅色為包絡，包絡即原始音頻訊號。</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">訊號的中間藍色部分是頻率很高的載波訊號，它的上下端是調幅訊號的包絡，此包絡就是所需要的音頻訊號。音頻的頻率相較於載波低很多。</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">上包絡訊號和下包絡訊號對稱，但是訊號相位相反，收音機最終只要其中的上包絡訊號，下包絡訊號不用，中間的高頻載波訊號也需要濾除。</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/6/6c/Simple_envelope_detector.svg&#039; /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/6/6c/Simple_envelope_detector.svg&#039; /&gt;&lt;/div&gt;</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>如右圖，調幅波訊號由左上方送入，電容與電阻在下方接地。三個元件的作用分別簡述如下：</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>如右圖，調幅波訊號由左上方送入，電容與電阻在下方接地。三個元件的作用分別簡述如下：</div></td></tr> <tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l35" >第35行：</td> <td colspan="2" class="diff-lineno">第42行：</td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電阻則濾除直流分量，消除捨棄下包絡時對原始訊號的偏移。</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#電阻則濾除直流分量，消除捨棄下包絡時對原始訊號的偏移。</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;https://upload.wikimedia.org/wikipedia/commons/d/d7/Analytic.svg&#039; width=&#039;180&#039; height=* /&gt;&lt;/div&gt;</del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">右圖為從調幅收音機天線收下來的調幅訊號。橫軸為時間，縱軸為振幅。藍色為載波；紅色為包絡，包絡即原始音頻訊號。</del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">訊號的中間藍色部分是頻率很高的載波訊號，它的上下端是調幅訊號的包絡，此包絡就是所需要的音頻訊號。音頻的頻率相較於載波低很多。</del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'>−</td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">上包絡訊號和下包絡訊號對稱，但是訊號相位相反，收音機最終只要其中的上包絡訊號，下包絡訊號不用，中間的高頻載波訊號也需要濾除。</del></div></td><td colspan="2"> </td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>====(一)二極體整流====</div></td></tr> <tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>&lt;div class=&#039;tright&#039;&gt;&lt;img src=&#039;http://img.my.csdn.net/uploads/201010/13/0_1286979146PeE6.gif&#039; width=&#039;300&#039; height=* /&gt;&lt;/div&gt;</div></td></tr> </table>

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