{"id":260,"date":"2012-06-16T13:48:41","date_gmt":"2012-06-16T13:48:41","guid":{"rendered":"http:\/\/www.bartola.co.uk\/valves\/?p=260"},"modified":"2012-06-16T13:48:41","modified_gmt":"2012-06-16T13:48:41","slug":"some-distortion-tests-on-the-26-dht","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2012\/06\/16\/some-distortion-tests-on-the-26-dht\/","title":{"rendered":"Some distortion tests on the 26 DHT"},"content":{"rendered":"<p>Having repaired the Pete Millett&#8217;s interface (hopefully) I tested two 26 DHT triodes I had at hand. One was an used Hytron ST valve and then the other test was an NOS White Whestinghouse ST valve, which is actually in pristine conditions.<\/p>\n<p>Both valves were tested with the same operating point:<\/p>\n<ul>\n<li>Vg=-10V<\/li>\n<li>Ia=5.5mA<\/li>\n<li>input signal adjusted to produce Vo=10Vrms (+22.22dBu)<\/li>\n<\/ul>\n<figure id=\"attachment_261\" aria-describedby=\"caption-attachment-261\" style=\"width: 584px\" class=\"wp-caption alignleft\"><a href=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"261\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2012\/06\/16\/some-distortion-tests-on-the-26-dht\/26-thd-1\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?fit=1243%2C772&amp;ssl=1\" data-orig-size=\"1243,772\" 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;}\" data-image-title=\"26 THD 1\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;26 Hytron ST valve THD @ +22.22dBu&lt;\/p&gt;\n\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?fit=840%2C521&amp;ssl=1\" class=\"size-large wp-image-261\" title=\"26 THD 1\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1-1024x635.jpg?resize=584%2C362\" alt=\"\" width=\"584\" height=\"362\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?resize=1024%2C635&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?resize=300%2C186&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?resize=483%2C300&amp;ssl=1 483w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-1.jpg?w=1243&amp;ssl=1 1243w\" sizes=\"auto, (max-width: 584px) 85vw, 584px\" \/><\/a><figcaption id=\"caption-attachment-261\" class=\"wp-caption-text\">26 Hytron ST valve THD @ +22.22dBu<\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<figure id=\"attachment_262\" aria-describedby=\"caption-attachment-262\" style=\"width: 584px\" class=\"wp-caption alignleft\"><a href=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" data-attachment-id=\"262\" data-permalink=\"https:\/\/www.bartola.co.uk\/valves\/2012\/06\/16\/some-distortion-tests-on-the-26-dht\/26-thd-2\/\" data-orig-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?fit=1243%2C772&amp;ssl=1\" data-orig-size=\"1243,772\" 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;}\" data-image-title=\"26 THD 2\" data-image-description=\"\" data-image-caption=\"&lt;p&gt;26 NOS White Whestinghouse ST valve THD @ +22.22dBu&lt;\/p&gt;\n\" data-large-file=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?fit=840%2C521&amp;ssl=1\" class=\"size-large wp-image-262\" title=\"26 THD 2\" src=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2-1024x635.jpg?resize=584%2C362\" alt=\"\" width=\"584\" height=\"362\" srcset=\"https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?resize=1024%2C635&amp;ssl=1 1024w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?resize=300%2C186&amp;ssl=1 300w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?resize=483%2C300&amp;ssl=1 483w, https:\/\/i0.wp.com\/www.bartola.co.uk\/valves\/wp-content\/uploads\/2012\/06\/26-THD-2.jpg?w=1243&amp;ssl=1 1243w\" sizes=\"auto, (max-width: 584px) 85vw, 584px\" \/><\/a><figcaption id=\"caption-attachment-262\" class=\"wp-caption-text\">26 NOS White Whestinghouse ST valve THD @ +22.22dBu<\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p>Well, I think I have\u00a0re-vindicated\u00a0the 26 DHT THD performance at a decent swing. Surprised to see the WW valve achieving 0.03% THD.<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Having repaired the Pete Millett&#8217;s interface (hopefully) I tested two 26 DHT triodes I had at hand. One was an used Hytron ST valve and then the other test was an NOS White Whestinghouse ST valve, which is actually in pristine conditions. Both valves were tested with the same operating point: Vg=-10V Ia=5.5mA input signal &hellip; <a href=\"https:\/\/www.bartola.co.uk\/valves\/2012\/06\/16\/some-distortion-tests-on-the-26-dht\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Some distortion tests on the 26 DHT&#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_post_was_ever_published":false,"_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":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[67],"tags":[779,6,784,39],"class_list":["post-260","post","type-post","status-publish","format-standard","hentry","category-thd","tag-779","tag-dht","tag-thd","tag-valve-tester-2"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-4c","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/260","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=260"}],"version-history":[{"count":1,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/260\/revisions"}],"predecessor-version":[{"id":263,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/260\/revisions\/263"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=260"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=260"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=260"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}