{"id":2588,"date":"2022-10-03T01:08:00","date_gmt":"2022-10-02T14:08:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2022\/10\/03\/update-on-the-direct-conversion-receiver-now-only-4-transistors\/"},"modified":"2025-07-22T18:02:55","modified_gmt":"2025-07-22T08:02:55","slug":"update-on-the-direct-conversion-receiver-now-only-4-transistors","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2022\/10\/03\/update-on-the-direct-conversion-receiver-now-only-4-transistors\/","title":{"rendered":"Update on the Direct Conversion Receiver &#8212; Now only 4 transistors"},"content":{"rendered":"<p><iframe loading=\"lazy\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" frameborder=\"0\" height=\"247\" src=\"https:\/\/www.youtube.com\/embed\/qtuj9CScNLM?rel=0\" title=\"YouTube video player\" width=\"440\"><\/iframe><\/p>\n<div><\/div>\n<div><span style=\"background-color: #f9f9f9; color: #030303; font-family: Roboto, Arial, sans-serif; font-size: 14px; white-space: pre-wrap;\"><b>I took a new look at the receiver, did some measurements, and decided to take out the RF amplifier and the AF pre-amp. The receiver works fine without them, another indication that they were unnecessary. Line-up is now: Band-pass filter, Mixer, VFO, AF amp. I think there is only 49 db of gain in the entire receiver, but it is useable with an un-amplified speaker, and is a bit too loud on ear buds. Not bad for just 4 transistors. And I think we could do this with just 3 (no need for the VFO buffer).<\/b><\/span><\/div>\n<div><span style=\"color: #030303; font-family: Roboto, Arial, sans-serif;\"><span style=\"font-size: 14px; white-space: pre-wrap;\"><b><br \/><\/b><\/span><\/span><\/div>\n<div><span style=\"color: #030303; font-family: Roboto, Arial, sans-serif;\"><span style=\"font-size: 14px; white-space: pre-wrap;\"><b>Here is the AF amplifier I used: <\/b><\/span><\/span> <\/p>\n<div class=\"separator\" style=\"clear: both; text-align: center;\"><a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2022\/10\/AF20amp20in20DC20RX.jpg\" imageanchor=\"1\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"2146\" data-original-width=\"2187\" height=\"314\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2022\/10\/AF20amp20in20DC20RX.jpg\" width=\"320\" \/><\/a><\/div>\n<p><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>I took a new look at the receiver, did some measurements, and decided to take out the RF amplifier and the AF pre-amp. The receiver works fine without them, another indication that they were unnecessary. Line-up is now: Band-pass filter, Mixer, VFO, AF amp. I think there is only 49 db of gain in the &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2022\/10\/03\/update-on-the-direct-conversion-receiver-now-only-4-transistors\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Update on the Direct Conversion Receiver &#8212; Now only 4 transistors&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":2589,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35,34,12],"tags":[],"class_list":["post-2588","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-direct-conversion","category-mixer-theory","category-tj-dc-rx"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2588","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\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=2588"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2588\/revisions"}],"predecessor-version":[{"id":2590,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2588\/revisions\/2590"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/2589"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=2588"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=2588"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=2588"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}