{"id":1076,"date":"2012-01-17T10:13:00","date_gmt":"2012-01-16T23:13:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2012\/01\/17\/another-jbot-amplifier-2\/"},"modified":"2025-07-21T10:49:10","modified_gmt":"2025-07-21T00:49:10","slug":"another-jbot-amplifier-2","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2012\/01\/17\/another-jbot-amplifier-2\/","title":{"rendered":"Another JBOT Amplifier"},"content":{"rendered":"<p><a onblur=\"try {parent.deselectBloggerImageGracefully();} catch(e) {}\" href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2012\/01\/P1010130-1.jpg\"><img decoding=\"async\" style=\"display: block; margin: 0px auto 10px; text-align: center; cursor: pointer; width: 400px; height: 299px;\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2012\/01\/P1010130-1.jpg\" alt=\"\" id=\"BLOGGER_PHOTO_ID_5698543488806428802\" border=\"0\" \/><\/a><span style=\"font-size:130%;\"><span style=\"font-weight: bold;\">Over the weekend I built another JBOT 5 watt linear amplifier (<a href=\"http:\/\/www.phonestack.com\/farhan\/jbot.html\">design by Farhan<\/a>). I used a nice piece of copper-clad board that Dave, W8NF, sent me (thanks again Dave). <\/span><\/p>\n<p><span style=\"font-weight: bold;\">This time I chickened out regarding the possible conductivity of the anodized heat sinks. I didn&#8217;t have any trouble with this on my first JBOT, but I worried that if the anodized layer gets flaked away, a heat sink might short one of those collectors to ground. To be on the safe side, I put small squares of Gorilla Tape on under the heat sinks. (PLEASE don&#8217;t tell me that Gorilla Tape is conductive!)<\/span><\/p>\n<p><span style=\"font-weight: bold;\">For T1 and T2 I used FT50-43 toroids instead of the TV baluns used by Farhan. He had recommended FT37-43&#8217;s as an alternative to the TV baluns, but I went with the slightly larger toroids. For T3 I rolled my own binocular core using four FT37-43 toroids stacked 2X2. <\/span><\/p>\n<p><span style=\"font-weight: bold;\">The amplifier has passed the smoke test. Next I have to put in the low pass filter (Steve Smith: Please note that I have left space on the board for the filter.) Then this version will face its real test when it goes into the 17 meter Azores SINGLE sideband rig. <\/span><br \/><\/span><br \/><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2012\/01\/P1010126-1.jpg\"><img decoding=\"async\" style=\"display: block; margin: 0px auto 10px; text-align: center; cursor: pointer; width: 400px; height: 299px;\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2012\/01\/P1010126-1.jpg\" alt=\"\" id=\"BLOGGER_PHOTO_ID_5698543983045560434\" border=\"0\" \/><\/a>Our book: &#8220;SolderSmoke &#8212; Global Adventures in Wireless Electronics&#8221;<a href=\"http:\/\/soldersmoke.com\/book.htm\">http:\/\/soldersmoke.com\/book.htm<\/a>Our coffee mugs, T-Shirts, bumper stickers: <a href=\"http:\/\/www.cafepress.com\/SolderSmoke\">http:\/\/www.cafepress.com\/SolderSmoke<\/a>Our Book Store: <a href=\"http:\/\/astore.amazon.com\/contracross-20\">http:\/\/astore.amazon.com\/contracross-20<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Over the weekend I built another JBOT 5 watt linear amplifier (design by Farhan). I used a nice piece of copper-clad board that Dave, W8NF, sent me (thanks again Dave). This time I chickened out regarding the possible conductivity of the anodized heat sinks. I didn&#8217;t have any trouble with this on my first JBOT, &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2012\/01\/17\/another-jbot-amplifier-2\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Another JBOT Amplifier&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":1077,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[84,66,235],"tags":[],"class_list":["post-1076","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-amplifier-theory","category-farhan","category-jbot"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/1076","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=1076"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/1076\/revisions"}],"predecessor-version":[{"id":1079,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/1076\/revisions\/1079"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/1077"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=1076"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=1076"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=1076"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}