{"id":5130,"date":"2016-01-03T13:54:24","date_gmt":"2016-01-03T13:54:24","guid":{"rendered":"http:\/\/www.bartola.co.uk\/valves\/?p=5130"},"modified":"2016-01-03T13:54:24","modified_gmt":"2016-01-03T13:54:24","slug":"flexible-ht-power-supply-part-ii","status":"publish","type":"post","link":"https:\/\/www.bartola.co.uk\/valves\/2016\/01\/03\/flexible-ht-power-supply-part-ii\/","title":{"rendered":"Flexible HT Power Supply (Part II)"},"content":{"rendered":"

Here are some picture of my slow progress on this flexible power supply<\/a>. \u00a0I started with the layout of the parts before any marks were made on the top plates:<\/p>\n

\"Working<\/a>
Working out the layout of the top plates<\/figcaption><\/figure>\n

 <\/p>\n

Once I was happy with the layout, I submitted myself to the mercy of the most dreadful job on earth which is\u00a0metalwork!<\/p>\n

<\/p>\n

\"Top<\/a>
Top plate ready for drilling<\/figcaption><\/figure>\n

Ok now that all was marked properly, the hard work was with the drill. The top plate is 4mm thick, so not easy work when cutting out large areas, like the oil caps. I was going to suffer this later. Here is the output of the first top plate:<\/p>\n

\"First<\/a>
First top plate. Metal work is finished and main components mounted<\/figcaption><\/figure>\n

The big 300VA transformer, the input choke LL1638, a mains relay (for input current surge), a pair of damper diode valve sockets, mains switches, neon indicators and some binding posts were added. This is how it looks from the top:<\/p>\n

\"Top<\/a>
Top plate<\/figcaption><\/figure>\n

Now, the hardest part included the oil caps which needed 50 and 60mm diameter holes!<\/p>\n

\"Again,<\/a>
Again, we measure carefully before any drilling is done<\/figcaption><\/figure>\n
\"After<\/a>
After a dreadful drilling exercise!<\/figcaption><\/figure>\n

Mostly use M3 \u00a0screws so we use counter-sink types where possible, the chokes use M4 bolts and the oil capacitors need a special supporting device like this:<\/p>\n

\"Mounting<\/a>
Mounting the oil caps with a square section aluminium bar.<\/figcaption><\/figure>\n

I added some heatsink to the mounting bar to ensure there is no potential electrical contact between the capacitor connectors and the chassis.<\/p>\n

Firstly I mounted the chokes and output connector:<\/p>\n

\"20H<\/a>
20H chokes added to the top plate as well as connector and earth post<\/figcaption><\/figure>\n

Then it was time to place the oil capacitors (2 x 100\u03bcF \/ 450VAC and 1 x 50\u03bcF \/ 450VAC):<\/p>\n

\"Filter<\/a>
Filter capacitors mounted<\/figcaption><\/figure>\n

I painted the capacitors with a dark grey primer for aluminium. They look nicer than they come in my view.<\/p>\n

Final step before I ran out of time was to add my hand-made tag strips to support additional components and a ground bar to use as star ground:<\/p>\n

\"Bottom<\/a>
Bottom of the 2nd top plate. Tag strips\u00a0and ground bar<\/figcaption><\/figure>\n

Well, there is plenty of work to be done still, but I hope you find this useful to get some building ideas.<\/p>\n

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

Here are some picture of my slow progress on this flexible power supply. \u00a0I started with the layout of the parts before any marks were made on the top plates:   Once I was happy with the layout, I submitted myself to the mercy of the most dreadful job on earth which is\u00a0metalwork!<\/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":[673,835],"tags":[610,836,782,533,216,115],"class_list":["post-5130","post","type-post","status-publish","format-standard","hentry","category-300b-amp","category-4p1l-pse-amp","tag-300b","tag-300b-amplifier","tag-4p1l","tag-4p1l-amplifier","tag-4p1l-pse","tag-ht-supply"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2r2tK-1kK","jetpack_likes_enabled":true,"jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/5130","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=5130"}],"version-history":[{"count":1,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/5130\/revisions"}],"predecessor-version":[{"id":5141,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/posts\/5130\/revisions\/5141"}],"wp:attachment":[{"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/media?parent=5130"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/categories?post=5130"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bartola.co.uk\/valves\/wp-json\/wp\/v2\/tags?post=5130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}