{"id":4468,"date":"2015-03-15T15:09:33","date_gmt":"2015-03-15T15:09:33","guid":{"rendered":"http:\/\/www.bartola.co.uk\/valves\/?p=4468"},"modified":"2015-03-15T15:09:33","modified_gmt":"2015-03-15T15:09:33","slug":"pl84-triode","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2015\/03\/15\/pl84-triode\/","title":{"rendered":"PL84 triode"},"content":{"rendered":"

\"TV-Roehre-PL84-Telefunken-m--Raute-ID1497-1497\"<\/a><\/p>\n

The PL84<\/a> pentode is very well known out there. I’m not going to write about it as there is plenty of information about the use of this pentode in push-pull amps, etc as well as comparisons with the EL84<\/a>, EL86<\/a> and Russian equivalents such as 6P14P<\/a>, 6P15P<\/a> and 6P43P<\/a>. I recommend you to check Klau’s work here<\/a>.<\/p>\n

I have a nice set of Telefunken PL84 which I may be using in triode mode as part of a Spud project I’ve been working on the design for some time. I’m interested in triode-strapped curves but also will be looking at tracing the Schade-feedback curves when I get the time to do so.<\/p>\n

I quickly found a sample valve that was close to the pentode specs at 90%. Good enough for my purpose so I proceed to trace the triode curves quickly in uTracer.<\/p>\n

<\/p>\n

I should have traced the curves\u00a0beyond\u00a0200V, but the 6 curves traced are good enough to generate an accurate triode model. A different story is developing a pentode\/tetrode model as you may be aware of.<\/p>\n

\"PL84-triode\"<\/a><\/p>\n

The triode model can be easily generated:<\/p>\n

\"PL84triodemodel\"<\/a>The spice Pl84-triode-spice <\/a>model\u00a0is very accurate. \u00a0The only disadvantage of this valve is the maximum 250V anode voltage which limits the available output power in a push-pull design compared to other similar valves like 6P14P, etc.<\/p>\n

With a 5K Zaa transformer you can get 7W in class A1 with a distortion a bit higher compared to 6P15P but not that much:<\/p>\n

\"PL84<\/a><\/p>\n

An extra 1.5W can be obtained if we use a 3K transformer instead:<\/p>\n

\"PL84<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

The PL84 pentode is very well known out there. I’m not going to write about it as there is plenty of information about the use of this pentode in push-pull amps, etc as well as comparisons with the EL84, EL86 and Russian equivalents such as 6P14P, 6P15P and 6P43P. I recommend you to check Klau’s … Continue reading “PL84 triode”<\/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":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[154,157,5],"tags":[715,716,717,714,718,713,719,720,682],"class_list":["post-4468","post","type-post","status-publish","format-standard","hentry","category-output-stage","category-push-pull-designs","category-valves","tag-6p14p","tag-6p15p","tag-6p43p","tag-el84","tag-el86","tag-pl84","tag-pl84-triode","tag-pl84-triode-model","tag-push-pull"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-1a4","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4468","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=4468"}],"version-history":[{"count":2,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4468\/revisions"}],"predecessor-version":[{"id":4476,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/4468\/revisions\/4476"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=4468"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=4468"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=4468"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}