{"id":8471,"date":"2019-11-21T14:05:00","date_gmt":"2019-11-21T03:05:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2019\/11\/21\/notes-and-video-on-doug-n0wvas-amazing-single-transistor-regenerative-receiver\/"},"modified":"2025-07-22T00:43:36","modified_gmt":"2025-07-21T14:43:36","slug":"notes-and-video-on-doug-n0wvas-amazing-single-transistor-regenerative-receiver","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2019\/11\/21\/notes-and-video-on-doug-n0wvas-amazing-single-transistor-regenerative-receiver\/","title":{"rendered":"Notes and Video on Doug N0WVA&#8217;s Amazing Single Transistor Regenerative Receiver"},"content":{"rendered":"<p><iframe loading=\"lazy\" allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" frameborder=\"0\" height=\"247\" src=\"https:\/\/www.youtube.com\/embed\/vMwDSNyIyxI\" width=\"440\"><\/iframe>  <\/p>\n<div style=\"background-color: white;\">\n<div class=\"separator\" style=\"clear: both; color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px; text-align: center;\"> <\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <i><b>When I had trouble getting the regen receiver in W2UW&#8217;s ET-1 circuit to work, I turned to the internet and &#8212; through AA7EE&#8217;s site &#8212; found the circuit of Doug N0WVA. This circuit has completely changed my attitude toward regen receivers. I have been exchanging e-mails with Doug &#8212; below is a compilation of the info and regen-wisdom that he has shared. More to follow&#8230; Thanks Doug. <\/b><\/i><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\">\n<div class=\"separator\" style=\"clear: both; text-align: center;\"> <a href=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2019\/11\/ET-2N0WVARX.jpg\" imageanchor=\"1\" style=\"margin-left: 1em; margin-right: 1em;\"><img loading=\"lazy\" decoding=\"async\" border=\"0\" data-original-height=\"772\" data-original-width=\"1200\" height=\"256\" src=\"https:\/\/www.homebrewradio.us\/blog\/wp-content\/uploads\/2019\/11\/ET-2N0WVARX.jpg\" width=\"400\" \/><\/a><\/div>\n<p> <b>From Doug N0WVA: <\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br \/><\/b> <b>I came up with the diode after exploring ways to ditch the source r\/c combo. The thinking was the closer I could get the source to ground the less voltage\/capacitance fluctuations the gate would see. Also I hated seeing everyone using .01 bypass to avoid audio oscillations and also losing audio gain. <\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br clear=\"none\" \/><\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b> The green LED works good but even better is directly grounding the source. Then feed a small negative bias through the gate leak resistor , adjustable via a potentiometer. <\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br clear=\"none\" \/><\/b><\/div>\n<div>\n<div dir=\"ltr\" style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b>On video, the audio is taken straight from the radio shack headphones that are connected to the audio transformer. The headphones are held directly to the phones case ( no hole for the microphone seen on the phone) <\/b><\/div>\n<div dir=\"ltr\" style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br clear=\"none\" \/><\/b><\/div>\n<div dir=\"ltr\"> <b style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\">The variometer is made with I think a 1.25 inch pill bottle and the tickler inside is around an inch in diameter pill bottle. I used a <\/b><span style=\"color: #1d2228; font-family: \"helvetica neue\" , \"helvetica\" , \"arial\" , sans-serif;\"><b>pharmaceutical<\/b><\/span><b style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> syringe&#8217;s outside tube for a shaft. The tickler form has a couple holes cut for the shaft to pass through, it is a friction fit, more like slits cut and the rod pushed through. I used the soldering iron to melt round holes on the actual outside coil form for the shaft to turn on. On the back of the shaft is a small screw that goes through the outside coil form and screws into the syringe center hole that holds it in place. The tickler is one turn, I think, and routed through the inside of the shaft via small holes melted with the soldering iron.<\/b><\/div>\n<div dir=\"ltr\" style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br \/><\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b>A couple tweeks to mention is instead of a resistor in the gate, use a choke for less noise, makes a big difference, especially if you listen to AM. Also I have been using a gimmick for the gate cap. Just maybe a #36 enamel wire wrapped around the hot tank lead 5 or 6 times and then I remove turns till the thing stops oscillating, then add a turn. This helps cut down even more on strong signal pulling. <\/b><\/div>\n<\/p><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br clear=\"none\" \/><\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b>I have always been on a quest for more performance out of the least parts. This design was about as far as it could go, I think&#8230;.<\/b><\/div>\n<div style=\"color: #1d2228; font-family: \"helvetica neue\", helvetica, arial, sans-serif; font-size: 16px;\"> <b><br \/><\/b><\/div>\n<\/p><\/div>\n<div style=\"background-color: white; color: #1d2228; font-family: \"Helvetica Neue\", Helvetica, Arial, sans-serif; font-size: 16px;\"> <b>I have never done any real sensitivity tests on the regen, so you have gone farther than me already. One thing was noticed though is the gate resistor does add a lot of noise, especially noticeable just under oscillation in AM detection mode. So I took a one meg 1\/4 watt resistor and wound as many turns of #38 wire on as I could, probably around 80 turns, then subbed it out for the gate leak. This dramatically improved the noise level just under oscillation. This was with a simple antenna band noise test. I think it also improved the noise under oscillating conditions. <\/b><\/div>\n<div style=\"background-color: white; color: #1d2228; font-family: \"Helvetica Neue\", Helvetica, Arial, sans-serif; font-size: 16px;\"> <b><br clear=\"none\" \/><\/b><\/div>\n<div style=\"background-color: white; color: #1d2228; font-family: \"Helvetica Neue\", Helvetica, Arial, sans-serif; font-size: 16px;\"> <b>Adding extra antenna coupling will probably help a lot, but, there is a point where we start getting too much strong signal pulling. The strong external bias battery trick will also improve this, although at the cost of extra parts.<\/b><\/div>\n","protected":false},"excerpt":{"rendered":"<p>When I had trouble getting the regen receiver in W2UW&#8217;s ET-1 circuit to work, I turned to the internet and &#8212; through AA7EE&#8217;s site &#8212; found the circuit of Doug N0WVA. This circuit has completely changed my attitude toward regen receivers. I have been exchanging e-mails with Doug &#8212; below is a compilation of the &hellip; <a href=\"https:\/\/www.homebrewradio.us\/blog\/2019\/11\/21\/notes-and-video-on-doug-n0wvas-amazing-single-transistor-regenerative-receiver\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Notes and Video on Doug N0WVA&#8217;s Amazing Single Transistor Regenerative Receiver&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":8472,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[85,87,148],"tags":[],"class_list":["post-8471","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-minimalist-radio","category-qrp","category-regens"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8471","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=8471"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8471\/revisions"}],"predecessor-version":[{"id":8473,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8471\/revisions\/8473"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/8472"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=8471"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=8471"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=8471"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}