{"id":615,"date":"2012-08-25T10:56:51","date_gmt":"2012-08-25T10:56:51","guid":{"rendered":"http:\/\/www.bartola.co.uk\/valves\/?p=615"},"modified":"2012-08-27T08:30:25","modified_gmt":"2012-08-27T08:30:25","slug":"a-super-linear-thd-and-fireworks","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2012\/08\/25\/a-super-linear-thd-and-fireworks\/","title":{"rendered":"A super-linear output valve and fireworks :)"},"content":{"rendered":"

Testing the 814 in triode mode<\/h1>\n

Worried about the G2 maximum voltage limit as per datasheet in class B, I decided to test the 814 carefully. So carefully that had a bit of smoke and fireworks (but not inside the valve)<\/p>\n

Paul Leclercq suggested adding the grid resistors in G2 and G3 and do some baby steps whilst testing this lady.<\/p>\n

Here is the test rig used:<\/p>\n

\"\"<\/a><\/p>\n

The valve is astonishingly linear. At 600V anode voltage and 50mA quiescent current the valve only produced THD=0.01% at 15Vrms output!<\/strong><\/p>\n

Internal pannel meter wasn’t disconnected and apparently didn’t survive the 600V exposure so blew up and a domino effect provided some interesting fireworks inside my bench supply (series MOSFET regulator) \ud83d\ude42<\/p>\n

Evidently something went wrong with an unexpected short to ground, couldn’t be bothered with doing some proper root cause analysis so shut everything down and brewed myself a cup of tea….<\/p>\n","protected":false},"excerpt":{"rendered":"

Testing the 814 in triode mode Worried about the G2 maximum voltage limit as per datasheet in class B, I decided to test the 814 carefully. So carefully that had a bit of smoke and fireworks (but not inside the valve) Paul Leclercq suggested adding the grid resistors in G2 and G3 and do some … Continue reading “A super-linear output valve and fireworks :)”<\/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":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[150,12,67,38,5],"tags":[182,183,178],"class_list":["post-615","post","type-post","status-publish","format-standard","hentry","category-4-65a-se-amplifier-2","category-dht-valves","category-thd","category-valve-tester","category-valves","tag-182","tag-814-thd","tag-814-triode"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-9V","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/615","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=615"}],"version-history":[{"count":3,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/615\/revisions"}],"predecessor-version":[{"id":623,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/615\/revisions\/623"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=615"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=615"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=615"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}