{"id":8424,"date":"2012-02-19T13:46:00","date_gmt":"2012-02-19T02:46:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2012\/02\/19\/words-of-wisdom-from-farhan\/"},"modified":"2012-02-19T13:46:00","modified_gmt":"2012-02-19T02:46:00","slug":"words-of-wisdom-from-farhan","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2012\/02\/19\/words-of-wisdom-from-farhan\/","title":{"rendered":"Words of Wisdom from Farhan"},"content":{"rendered":"<p><span style=\"font-weight: bold;font-size:130%;\" ><span style=\"font-size:100%;\">I read the mail of the BITX20 group. Here is some good advice from Farhan:<\/p>\n<p>I have often seen builders finishing an entire build, then powering it<br \/>up to face the frustration of a dead circuit. I suspect that the<br \/>trouble is with our kit building mind set. As a kit builder, we assume<br \/>that if it has worked well for a few hundred others, there is no<br \/>reason for it to not work for us. But the truth is more sobering &#8230;<br \/>Of the hundred odd components, any of them could get swapped by<br \/>another, or a bad solder, wrong polarity, etc. can all conspire to<br \/>thwart your attempts. The bitx manuals are really some of the best<br \/>produced in the recent years and yet, even with leonard&#8217;s videos,<br \/>troubleshooting kits is a challenge.<br \/>I am proposing a more elaborate, slower but surer approach to building the bitx.<\/p>\n<p>It is as follows: build it one stage at a time, use one stage to test<br \/>the next. For instance, one could start with the bfo first. Just a<br \/>single transistor with the crystal. Then use an RF probe to check the<br \/>rf output. If there is no output, then sort that out before proceeding<br \/>to the next stage. With the addition of the buffer amp, the output<br \/>should go up. Then one could proceed to the audio amp. Injecting audio<br \/>from your mp3 player or computer could check that it works. Next,<br \/>replace the audio source with the mic amp, this tests the mic amp.<br \/>Now, if you add the two diode modulator, you should be able to receive<br \/>the dsb at 10 MHz on your HF transceiver.<\/p>\n<p>This approach tests each stage individually and in isolation before<br \/>proceeding to the next. It also provides wholesome education to the<br \/>builder. In software industry, it is called a &#8216;test driven<br \/>development&#8217; method of developing software.<\/p>\n<p>In the end, this approach is no slower than the current approach,<br \/>except that surprises are not kept for the last.<\/p>\n<p>I am sure that some of us can come out with a sequence of stages to<br \/>build where each stage is tested using the previous stage.<\/p>\n<p>As much as bitx is about building it cheap, it is also about learning<br \/>your radio from inside. Bitx is also education on the cheap, don&#8217;t<br \/>give up that opportunity.<\/p>\n<p>&#8211; farhan VU2ESE<br \/><\/span><br \/><\/span> 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>I read the mail of the BITX20 group. Here is some good advice from Farhan: I have often seen builders finishing an entire build, then powering itup to face the frustration of a dead circuit. I suspect that thetrouble is with our kit building mind set. As a kit builder, we assumethat if it has &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2012\/02\/19\/words-of-wisdom-from-farhan\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Words of Wisdom from Farhan&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28,66,105,25],"tags":[],"class_list":["post-8424","post","type-post","status-publish","format-standard","hentry","category-bitx20","category-farhan","category-kits","category-troubleshooting"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8424","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=8424"}],"version-history":[{"count":0,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8424\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=8424"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=8424"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=8424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}