{"id":114,"date":"2009-06-27T19:32:42","date_gmt":"2009-06-27T23:32:42","guid":{"rendered":"http:\/\/www.cchsu.com\/art-en\/?p=114"},"modified":"2009-07-30T03:03:44","modified_gmt":"2009-07-30T07:03:44","slug":"diy-uhf-antenna","status":"publish","type":"post","link":"http:\/\/www.cchsu.com\/art-en\/2009\/06\/27\/114\/","title":{"rendered":"DIY UHF antenna"},"content":{"rendered":"<p>\u00a0I&#8217;ve just bought a TV few days ago and don&#8217;t want to pay cable\/satellite companies hefty monthly subscription.\u00a0 So the first step is to start with some easy sources, like local TV stations.\u00a0 I had an antenna from BestBuy before, and the reception was completely unacceptable.\u00a0 Doing a little Googling showed me that poor peons like me shall cook own antenna.<\/p>\n<p>The US is already transferred to digital TV in June, so I need only build a UHF antenna.\u00a0 There are many different types of antenna on the web, for example, <a href=\"http:\/\/www.youtube.com\/watch?v=EWQhlmJTMzw\">the bow-tie on YouTube<\/a>, or the <a href=\"http:\/\/www.digitalhome.ca\/ota\/superantenna\/index.htm\">Gray Hoverman<\/a> (a.k.a super antenna).\u00a0\u00a0I&#8217;ve also found another design from forums in Taiwan (<a href=\"http:\/\/www.tvrobbs.com\/showthread.php?s=f80537057e7b9b581394392f0c7ed15d&amp;threadid=2852\">four diamonds<\/a>, demonstrated in the following).\u00a0 Since the UHF frequency of Taiwan\u00a0(600MHz) is the same in the US, I decided to give this four diamonds a try because it&#8217;s easier to\u00a0DIY than bow-ties and Gray Hoverman.<\/p>\n<p>Materials needed:<\/p>\n<p><a href=\"http:\/\/www.amazon.com\/RCA-Matching-Transformer-VH54\/dp\/B00005T3EY\">RCA Matching transformer<\/a>: the link goes to Amazon, but I bought it at Home Depot like 4 bucks after tax<\/p>\n<p>7 feet of 12 Gauge copper wire (Home Depot sold it 26 cents per feet)<\/p>\n<p>The structure of this antenna is shown here<\/p>\n<p><a class=\"tt-flickr tt-flickr-Medium\" title=\"IMG_1345\" href=\"http:\/\/www.flickr.com\/photos\/24238190@N00\/3666682674\/\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/farm4.static.flickr.com\/3599\/3666682674_12ba97f735.jpg\" alt=\"IMG_1345\" width=\"375\" height=\"500\" \/><\/a><\/p>\n<p>Use the copper wire to build four equal size squares of 12.6cm long in edge (4.96 inches, it&#8217;s much easier to steal my kid&#8217;s ruler which had both inches and cm on\u00a0it).\u00a0 I drew the shape on a cardboard first, and then started the wire routing.\u00a0 The wire I use is insulated.\u00a0 If your&#8217;s is not, make sure you insulate the cross-over of the diamonds except where you connect to the transformer.\u00a0 Once the diamonds were laid flat on the card board, we could connect the transformer onto it.\u00a0 I use electrical tapes because it&#8217;s, you know,\u00a0easy.<\/p>\n<p>Here&#8217;s the finished picture, crystal clear HD image from NBC.\u00a0 My place is in Torrance and I&#8217;ve got 30+ stations with this DIY antenna.\u00a0 REALLY HAPPY.<\/p>\n<p><a class=\"tt-flickr tt-flickr-Medium\" title=\"IMG_1342\" href=\"http:\/\/www.flickr.com\/photos\/24238190@N00\/3665747903\/\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone\" src=\"http:\/\/farm4.static.flickr.com\/3625\/3665747903_383113a99f.jpg\" alt=\"IMG_1342\" width=\"500\" height=\"375\" \/><\/a><\/p>\n<p>I&#8217;m not an antenna engineer, thus unfortunately\u00a0I don&#8217;t know exactly\u00a0why this thing works and how good it is.\u00a0 Here are the things I know of from its designer:<\/p>\n<ol>\n<li>This antenna is directional, you need to find the best spot in your place to get good signal<\/li>\n<li>The four diamonds MUST be posed vertical (up to down).\u00a0 Horizontal (left to right) won&#8217;t work.<\/li>\n<li>You can add reflection board (sheet of aluminum, 8cm apart parallel to the antenna) to enhance its signal.\u00a0 I didn&#8217;t do so because I&#8217;ve already got strong enough signal.<\/li>\n<\/ol>\n<p>This thing can definitely be beautified and that will be my next project.\u00a0 Meanwhile I&#8217;m going to enjoy some TV first.<\/p>\n<p><a href=\"http:\/\/www.cchsu.com\/art-en\/2009\/07\/29\/133\/\">More on DIY UHF antenna <\/a>&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00a0I&#8217;ve just bought a TV few days ago and don&#8217;t want to pay cable\/satellite companies hefty monthly subscription.\u00a0 So the first step is to start with some easy sources, like local TV stations.\u00a0 I had an antenna from BestBuy before, and the reception was completely unacceptable.\u00a0 Doing a little Googling showed me that poor peons [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"_links":{"self":[{"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/posts\/114"}],"collection":[{"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/comments?post=114"}],"version-history":[{"count":7,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/posts\/114\/revisions"}],"predecessor-version":[{"id":137,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/posts\/114\/revisions\/137"}],"wp:attachment":[{"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/media?parent=114"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/categories?post=114"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.cchsu.com\/art-en\/wp-json\/wp\/v2\/tags?post=114"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}