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From Pozar book i cant confirm the final relation" /> <meta property="og:image" content="https://drive.google.com/file/d/1S9GEWEQ7uU-xh8I-pKmlON5cqGXettWm/view?usp=sharing" /> <script src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/cache/Minify/2056fb24e46c45ba282d1122c3e5f043.js?v=SE" type="text/javascript"></script> <script src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/cache/Minify/e3420cb377e58f1bada52aeada61c1f7.js?v=E" type="text/javascript"></script> <script src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/cache/Minify/cbf5f61108ab733c24e3258e12ee4a5a.js?v=E" type="text/javascript"></script> <script src="https://platform.twitter.com/widgets.js" type="text/javascript"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS_HTML,Safe" type="text/javascript"></script> <script charset="utf-8" id="gotopage-ptl" type="text/template"> <div class="JumpToPage Hidden"> <form name="JumpToPage" method="get" action="{url}"> Page: <input type="text" autofocus name="Page" value="" autocomplete="off" /> </form> </div> </script> <style type="text/css"> div.Message, div.Excerpt {line-height:19px !important;} </style> <style type="text/css"> div.ac_results.related, div.ac_results.searchbar { top: 52px !important; } </style> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-24139105-2', 'auto'); ga('send', 'pageview', { 'dimension1': 'Guest' }); </script> <div id='div-gpt-ad-1511681685810-0' style='min-width: 728px; min-height: 90px; margin-top: 70px; margin-bottom: -50px;'> <script> googletag.cmd.push(function() { googletag.display('div-gpt-ad-1511681685810-0'); }); </script> </div></head> <body id="vanilla_discussion_index" class="Vanilla Discussion Index "> <div id="Matte"></div> <div id="Frame" class="Flat"> <div id="Head" class="MainNav"><div id="HeadMatte"></div> <div class="Banner Menu"> <h1><a class="Title" href="https://www.microwaves101.com"><span><img width="163" height="32" style="padding-top:10px;padding-bottom:10px;height:32px;" class="BannerLogo" src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/uploads/LQC11ZFYDP1W.png" alt="Microwaves 101 Discussion Board" /></span></a></h1><ul id="Menu"><li><a class="ActiveApp" href="/discussions">Forum</a></li><li><a href="/members">Members</a></li><li><a class="ApplyButton" href="/entry/register?Target=discussion%2F221%2Fdirectivity%2Flatest%2Fcomment">Sign Up</a></li><li><a class="SignInPopup" href="/entry/signin?Target=discussion%2F221%2Fdirectivity%2Flatest%2Fcomment">Sign In</a></li><li class="mp"><a class="mp"></a></li></ul> <div id="Search"><form method="get" action="/search" style="width:auto"> <div> <input type="submit" id="Form_Go" value="  " style="float:right;margin-left: 9px;" class="Button" /> <input type="text" id="Form_Search" name="Search" value="" autocapitalize="none" spellcheck="false" autocorrect="off" autocomplete="off" style="float:right" class="InputBox" /></div> </form></div> </div> </div> <div id="Body"> <div id="Content"><div class="Tabs HeadingTabs DiscussionTabs FirstPage"> <div class="SubTab"><span class="DiscussionTitle"><h2><a href="/discussion/221/directivity">directivity</a></h2></span> <div class="ClearFix"></div> </div> </div> <ul class="DataList MessageList Discussion FirstPage"> <li class="Item Comment FirstComment nc" id="Discussion_221"> <div class="Comment"> <span class="Author"> <a title="GeorgeVeropoulos" href="/profile/5987/georgeveropoulos" class="ProfileLink"><img src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/uploads/userpics/446/nOWWRVWTOPFWU.png" class="ProfilePhotoMedium" /></a><a href="/profile/5987/georgeveropoulos">GeorgeVeropoulos</a> </span> <div class="CommentInfo"> <span style="cursor:default;" title="Likes Earned">0</span> </div> <div class="Message"> HI<br /> i m lookig a relation about direcrivity of Directional coupler.. From Pozar book<br /> i cant confirm the final relation<br /> <br /> <br /> <img style="cursor:pointer;" src="https://drive.google.com/file/d/1S9GEWEQ7uU-xh8I-pKmlON5cqGXettWm/view?usp=sharing" alt="view?usp=sharing" class="bbcode_img" /> </div> <div class="Meta"> <span class="Author"> <a href="/profile/5987/georgeveropoulos">GeorgeVeropoulos</a> </span> <span class="DateCreated"> <a href="/discussion/221/directivity/p1" class="Permalink" id="Message_1" rel="nofollow"><time title="2024-02-21T11:43:37+00:00" datetime="2024-02-21T11:43:37+00:00" class="newtime"></time></a> </span> <span class="EditComment edit-more"><a title="Options" href="" class="show-more-opts" style="color:#888">Options</a></span><span class="pfmm EditComment edit-share"><a title="Share" href="" class="share-link" style="color:#888">Share</a></span><span class="Like"><span class="likes">0</span><span title="Likes" class="LikeThisLiked"><span class="like-spacer"></span></span></span> </div> </div> </li> <li class="Item Comment nc" id="Comment_486"> <div class="Comment"> <span class="Author"> <a title="rfdave" href="/profile/19/rfdave" class="ProfileLink"><img src="//1mkvvvtqkb5hve14sg-cdn.plushcontent.com/uploads/userpics/028/n6P9MH7LFBAXI.png" class="ProfilePhotoMedium" /></a><a href="/profile/19/rfdave">rfdave</a> </span> <div class="CommentInfo"> <span style="cursor:default;" title="Likes Earned">0</span> </div> <div class="Message"> Your post is a bit unclear.<br /> I like this note from Marki Microwave for Couplers and directivity.<br /> <br /> <a href="https://markimicrowave.com/technical-resources/white-papers/power-dividers-directional-couplers-primer/" target="_blank" rel="nofollow">https://markimicrowave.com/technical-resources/white-papers/power-dividers-directional-couplers-primer/</a> </div> <div class="Meta"> <span class="Author"> <a href="/profile/19/rfdave">rfdave</a> </span> <span class="DateCreated"> <a href="/discussion/comment/486" class="Permalink" id="Message_2" rel="nofollow"><time title="2024-02-28T03:21:39+00:00" datetime="2024-02-28T03:21:39+00:00" class="newtime"></time></a> </span> <span class="EditComment edit-more"><a title="Options" href="" class="show-more-opts" style="color:#888">Options</a></span><span class="pfmm EditComment edit-share"><a title="Share" href="" class="share-link" style="color:#888">Share</a></span><span class="Like"><span class="likes">0</span><span title="Likes" class="LikeThisLiked"><span class="like-spacer"></span></span></span> </div> </div> </li> </ul> <div class="BaseTab PageOne"></div><script> $("a.show-more-opts").live("click", function(e) { e.preventDefault(); 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