{"id":3199,"date":"2012-06-25T19:45:37","date_gmt":"2012-06-26T02:45:37","guid":{"rendered":"http:\/\/rustybolt.info\/wordpress\/?p=3199"},"modified":"2012-08-10T12:56:54","modified_gmt":"2012-08-10T19:56:54","slug":"2012-06-25","status":"publish","type":"post","link":"https:\/\/rustybolt.info\/wordpress\/?p=3199","title":{"rendered":"2012-06-25 Watson&#8217;s 3 Transistor Earphone Amplifier"},"content":{"rendered":"<p><a href=\"http:\/\/rustybolt.info\/wordpress\/?attachment_id=3539\" rel=\"attachment wp-att-3539\"><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-medium wp-image-3539\" title=\"DSC_0107S2\" src=\"http:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2012\/06\/DSC_0107S2-300x223.jpg\" alt=\"\" width=\"300\" height=\"223\" srcset=\"https:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2012\/06\/DSC_0107S2-300x223.jpg 300w, https:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2012\/06\/DSC_0107S2.jpg 805w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a>This amplifier has been around for awhile, however the date code on the Altoids tin is &#8220;Use by 22 Aug 06&#8221;, so it had to be made sometime not long before that date or later, most likely later.\u00a0 I used a high gain, low noise Japanese transistor (looks like a 2SD636) for the preamplifier, and two 2N3904 transistors.\u00a0 The Altoids tin was a convenient size to hold everything, as can be seen in the pic.<\/p>\n<p>Originally the miniature electret condenser microphone on the left side of the tin was directly connected to the\u00a0 input.\u00a0 Later I added the microphone jack.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>This amplifier has been around for awhile, however the date code on the Altoids tin is &#8220;Use by 22 Aug 06&#8221;, so it had to be made sometime not long before that date or later, most likely later.\u00a0 I used a high gain, low noise Japanese transistor (looks like a 2SD636) for the preamplifier, and<a href=\"https:\/\/rustybolt.info\/wordpress\/?p=3199\"> <\/p>\n<p> (Read More&#8230;)<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-3199","post","type-post","status-publish","format-standard","hentry","category-audio"],"_links":{"self":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3199","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3199"}],"version-history":[{"count":8,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3199\/revisions"}],"predecessor-version":[{"id":3537,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/3199\/revisions\/3537"}],"wp:attachment":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3199"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3199"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3199"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}