{"id":3974,"date":"2021-06-22T13:22:00","date_gmt":"2021-06-22T17:22:00","guid":{"rendered":"https:\/\/twiar.net\/?p=3974"},"modified":"2021-06-19T13:54:55","modified_gmt":"2021-06-19T17:54:55","slug":"via-hackaday-vacuum-tube-magic-comes-to-the-741","status":"publish","type":"post","link":"https:\/\/twiar.net\/2021\/06\/22\/via-hackaday-vacuum-tube-magic-comes-to-the-741\/","title":{"rendered":"via HACKADAY: Vacuum Tube Magic Comes To The 741"},"content":{"rendered":"<div><img decoding=\"async\" style=\"max-width: 600px;\" src=\"https:\/\/hackaday.com\/wp-content\/uploads\/2021\/06\/building-the-largest-741-opamp-in-the-world-with-vacuum-tubes-plus-555-timer-update-qp4l-rwhbesmkv-shot0005_featured.png?w=800\" \/>Some of you may remember a recent project that featured on these pages, a 555 timer reproduced using vacuum tubes. Its creator [Usagi Electric] was left at loose ends while waiting for a fresh PCB revision of the 555 to be delivered, so set about creating a new vacuum tube model of a popular chip,\u00a0<a href=\"https:\/\/www.youtube.com\/watch?v=Qp4l-RWHbes\" target=\"_blank\" rel=\"noopener\">this time the ubiquitous 741 op-amp<\/a>. (Video, embedded below.)<\/p>\n<p>The circuit is fairly straightforward, using six small pentodes. The first two are\u00a0 a long-tailed pair as might be expected, followed by two gain stages, then a final gain stage feeding a cathode follower with feedback. It\u2019s neatly built on a PCB with IC-style \u201cpins\u201d made from more PCB material, then put in a huge replication of an IC socket on a wooden baseboard.<\/p>\n<div>via Blog \u2013 Hackaday <a href=\"https:\/\/hackaday.com\/2021\/06\/19\/vacuum-tube-magic-comes-to-the-741\/\" target=\"_blank\" rel=\"noopener\">https:\/\/hackaday.com\/2021\/06\/19\/vacuum-tube-magic-comes-to-the-741\/<\/a><\/div>\n<\/div>\n<div><\/div>\n<div>\n<p><iframe loading=\"lazy\" title=\"Building the Largest 741 OpAmp in the World with Vacuum Tubes (Plus 555 Timer Update)\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/Qp4l-RWHbes?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Some of you may remember a recent project that featured on these pages, a 555&#8230;<\/p>\n","protected":false},"author":5,"featured_media":199,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rop_custom_images_group":[],"rop_custom_messages_group":[],"rop_publish_now":"initial","rop_publish_now_accounts":{"twitter_16139062_16139062":""},"rop_publish_now_history":[],"rop_publish_now_status":"pending","footnotes":""},"categories":[109,108],"tags":[1452,1451,110,103,111,27,992],"class_list":["post-3974","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hackaday","category-makers","tag-555-timer","tag-741-op-amp","tag-hackaday","tag-ifttt","tag-makerspace","tag-news","tag-vacuum-tubes"],"_links":{"self":[{"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/posts\/3974","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/comments?post=3974"}],"version-history":[{"count":2,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/posts\/3974\/revisions"}],"predecessor-version":[{"id":3979,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/posts\/3974\/revisions\/3979"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/media\/199"}],"wp:attachment":[{"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/media?parent=3974"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/categories?post=3974"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/twiar.net\/wp-json\/wp\/v2\/tags?post=3974"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}