{"id":2146,"date":"2022-11-17T11:24:00","date_gmt":"2022-11-17T00:24:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2022\/11\/17\/sdr-direct-sampling-the-end-of-homebrewing-as-we-know-it\/"},"modified":"2025-07-22T18:02:55","modified_gmt":"2025-07-22T08:02:55","slug":"sdr-direct-sampling-the-end-of-homebrewing-as-we-know-it","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2022\/11\/17\/sdr-direct-sampling-the-end-of-homebrewing-as-we-know-it\/","title":{"rendered":"SDR Direct Sampling:  The End of Homebrewing (as we know it)"},"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\/WmaB4dIh99Y?rel=0\" title=\"YouTube video player\" width=\"440\"><\/iframe><\/p>\n<p><b>I sometimes hear hams claim that our efforts to build simple direct conversion receivers are &#8220;very relevant&#8221; to modern technology and are &#8220;directly applicable&#8221; to today&#8217;s communications techniques. These hams will say that direct conversion receivers are at the heart of modern rigs. <\/b><\/p>\n<p><b>That&#8217;s a nice thought, and it might have been true in the past, but I don&#8217;t think it is true anymore. <\/b><\/p>\n<p><b>I think the future is what you see written on the black box (!) that encloses the receiver in the above video: &#8220;DIRECT SAMPLING RECEIVER.&#8221; In the recent past we did have two direct conversion receivers in the front end of SDR receiving systems. These receivers produced I and Q signals that were fed into the computer (often via the sound card). That was nice. <\/b><\/p>\n<p><b>But the writing has been on the wall for a long time. There is no longer a need for all that direct conversion and I and Q. Just put a fast Analog-to-Digital converter chip at the front end, convert the entire HF spectrum to a digital stream, and send that stream to your computer. Or to another part of your &#8220;rig.&#8221; As in the ubiquitous 7300. <\/b><\/p>\n<p><b>I don&#8217;t mean to be a Luddite here. That big waterfall is very nice. The receiver sounds great. But I am a homebrewer and I prefer to build my own gear. Ordering this black box on my phone, having it delivered by Bezos to my front step, and then updating the driver, is not what I consider homebrew radio. <\/b><\/p>\n<p><b>A couple of things I spotted: The Si5351 chip in the box &#8212; at least one part was recognizable. And the completely vertical skirts on all the SSB signals &#8212; lots of 7300s out there. <\/b><\/p>\n<p><b>Hey, to each his own, YMMV, whatever floats your boat. Just don&#8217;t kid yourself into thinking that our beloved DC receivers are still somehow being used in these modern black boxes. <\/b><\/p>\n","protected":false},"excerpt":{"rendered":"<p>I sometimes hear hams claim that our efforts to build simple direct conversion receivers are &#8220;very relevant&#8221; to modern technology and are &#8220;directly applicable&#8221; to today&#8217;s communications techniques. These hams will say that direct conversion receivers are at the heart of modern rigs. That&#8217;s a nice thought, and it might have been true in the &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2022\/11\/17\/sdr-direct-sampling-the-end-of-homebrewing-as-we-know-it\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;SDR Direct Sampling:  The End of Homebrewing (as we know it)&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35,40,61],"tags":[],"class_list":["post-2146","post","type-post","status-publish","format-standard","hentry","category-direct-conversion","category-sdr","category-si5351"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2146","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=2146"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2146\/revisions"}],"predecessor-version":[{"id":11343,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/2146\/revisions\/11343"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=2146"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=2146"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=2146"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}