{"id":9976,"date":"2021-08-20T13:49:50","date_gmt":"2021-08-20T12:49:50","guid":{"rendered":"https:\/\/www.bartola.co.uk\/valves\/?p=9976"},"modified":"2021-08-29T09:05:21","modified_gmt":"2021-08-29T08:05:21","slug":"ll1943-sut-pcb-v02-balanced-option","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2021\/08\/20\/ll1943-sut-pcb-v02-balanced-option\/","title":{"rendered":"LL1943 \/ LL1933 SUT PCB V02 &#8211; Balanced option"},"content":{"rendered":"<p>After a long time, decided to update the PCB of the <a href=\"https:\/\/www.bartola.co.uk\/valves\/for-sale\/ll1943-pcb\/\">LL1943 SUT <\/a>to provide extra flexibility on the grounding connection. This is in essence to ensure no ground loops and noise when either using balanced or un-balanced cabling from the cartridge into the PCB:<\/p>\n<figure id=\"attachment_9980\" aria-describedby=\"caption-attachment-9980\" style=\"width: 768px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"9980\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2021\/08\/20\/ll1943-sut-pcb-v02-balanced-option\/ll1943-mc-sut-pcb-v02-2-3\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?fit=1875%2C2500&amp;ssl=1\" data-orig-size=\"1875,2500\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;1.8&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;iPhone 11&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1629462093&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;4.25&quot;,&quot;iso&quot;:&quot;125&quot;,&quot;shutter_speed&quot;:&quot;0.01&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"LL1943 MC SUT PCB v02-2\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?fit=768%2C1024&amp;ssl=1\" class=\"wp-image-9980 size-large\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=768%2C1024&#038;ssl=1\" alt=\"\" width=\"768\" height=\"1024\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=768%2C1024&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=225%2C300&amp;ssl=1 225w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=1152%2C1536&amp;ssl=1 1152w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=1536%2C2048&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?resize=1200%2C1600&amp;ssl=1 1200w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?w=1875&amp;ssl=1 1875w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-2-2.jpg?w=1680&amp;ssl=1 1680w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><\/a><figcaption id=\"caption-attachment-9980\" class=\"wp-caption-text\">LL1943: note the additional jumpers added<\/figcaption><\/figure>\n<p><a href=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"9978\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2021\/08\/20\/ll1943-sut-pcb-v02-balanced-option\/ll1943-mc-sut-pcb-v02-1\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?fit=2000%2C1211&amp;ssl=1\" data-orig-size=\"2000,1211\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;1.8&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;iPhone 11&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;1629462050&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;4.25&quot;,&quot;iso&quot;:&quot;64&quot;,&quot;shutter_speed&quot;:&quot;0.01&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;1&quot;}\" data-image-title=\"LL1943 MC SUT PCB v02-1\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?fit=840%2C509&amp;ssl=1\" class=\"aligncenter size-large wp-image-9978\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=840%2C509&#038;ssl=1\" alt=\"\" width=\"840\" height=\"509\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=1024%2C620&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=300%2C182&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=768%2C465&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=1536%2C930&amp;ssl=1 1536w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?resize=1200%2C727&amp;ssl=1 1200w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?w=2000&amp;ssl=1 2000w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-MC-SUT-PCB-v02-1.jpg?w=1680&amp;ssl=1 1680w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/a>The additional jumpers are in line with the recommendations from the <a href=\"https:\/\/www.lundahltransformers.com\/wp-content\/uploads\/datasheets\/1943.pdf\">Datasheet<\/a>. Here is the diagram:<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?ssl=1\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"9981\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2021\/08\/20\/ll1943-sut-pcb-v02-balanced-option\/ll1943-pcb-diagram\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?fit=1181%2C887&amp;ssl=1\" data-orig-size=\"1181,887\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"LL1943 PCB Diagram\" data-image-description=\"\" data-image-caption=\"\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?fit=840%2C631&amp;ssl=1\" class=\"aligncenter size-large wp-image-9981\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?resize=840%2C631&#038;ssl=1\" alt=\"\" width=\"840\" height=\"631\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?resize=1024%2C769&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?resize=300%2C225&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?resize=768%2C577&amp;ssl=1 768w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2021\/08\/LL1943-PCB-Diagram.jpg?w=1181&amp;ssl=1 1181w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 1362px) 62vw, 840px\" \/><\/a>For a fixed connection (like in most of the cases once preamp has been tuned\/optimised) you can replace the jumpers by solid core wire jumpers soldered to the pad for best connection and performance.<\/p>\n<p>This PCB is also for the <a href=\"https:\/\/www.lundahltransformers.com\/wp-content\/uploads\/datasheets\/1933.pdf\">LL1933<\/a>. Basically is the same SUT but with 1+1:8+8 instead of 1+1:16+16 windings.<\/p>\n<p>I made a small batch (I won&#8217;t need more than 2 or 4! myself) so the remaining will go on first-come-first-serve basis.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>After a long time, decided to update the PCB of the LL1943 SUT to provide extra flexibility on the grounding connection. This is in essence to ensure no ground loops and noise when either using balanced or un-balanced cabling from the cartridge into the PCB: The additional jumpers are in line with the recommendations from &hellip; <a href=\"https:\/\/www.bartola.co.uk\/valves\/2021\/08\/20\/ll1943-sut-pcb-v02-balanced-option\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;LL1943 \/ LL1933 SUT PCB V02 &#8211; Balanced option&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1179,156,421],"tags":[894,1415,1414,1416,1303,1304,489,1306],"class_list":["post-9976","post","type-post","status-publish","format-standard","hentry","category-pcb","category-pre-amplifier-valves","category-turntable","tag-bartola-pcb","tag-ll1933","tag-ll1933-pcb","tag-ll1933-sut","tag-ll1943","tag-ll1943-pcb","tag-lundahl-transformers","tag-mc-sut"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-2AU","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/9976","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/comments?post=9976"}],"version-history":[{"count":3,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/9976\/revisions"}],"predecessor-version":[{"id":10044,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/9976\/revisions\/10044"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=9976"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=9976"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=9976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}