{"id":6115,"date":"2026-02-27T08:16:52","date_gmt":"2026-02-27T06:16:52","guid":{"rendered":"http:\/\/www.retro.co.za\/blog\/?p=6115"},"modified":"2026-02-27T09:24:20","modified_gmt":"2026-02-27T07:24:20","slug":"munz-goes-to-china","status":"publish","type":"post","link":"http:\/\/www.retro.co.za\/blog\/?p=6115","title":{"rendered":"Munz goes to China"},"content":{"rendered":"

Earl Munz was a 1940s salesman who realised that about half the components in the television-sets-du-jour were only needed in edge cases, and he (correctly) reasoned that there was a lucrative market in the middle. Removing (“diking<\/a>“) the “excess” components resulted in a cheap TV that worked well enough in the city. Reliability was actually improved, because fewer components. Yea well, that was then. This… is now.<\/p>\n

\"\"<\/p>\n

Here we have a USB power hub from the good fellows over at the Value Store<\/a>. Chinesium AF. It lasted… surprisingly long. Maybe a whole six months in service. Whoop whoop. Note the suspicious-looking bulge under the one “5V 2.1A” port*.<\/p>\n

\"\"<\/p>\n

Some force was required to pull it apart, because the bulge is a capacitor that got hot and welded itself to the plastic top.<\/p>\n

\"\"<\/p>\n

Hmmm. Space for four capacitors, but only one fitted (and “EC2” in the high-voltage department also got diked).<\/p>\n

The casualty is marked “1000uF 10V Low ESR 105C”. And it’s 8×12, maybe 8.5×13, which at current capacitor density (assuming they’re not lying about the “Low ESR) is either 470uF at 10V or 1000uF at 6.3V, and that’s pushing it. I suspect the latter, 1000uF at 6.3V (USB is 5V, so that’s OK, right?).<\/p>\n

So, the majority of capacitors got Munzed, and then the solo remaining\u00a0 catyarid<\/a> failed after carrying the load for too long.<\/p>\n

\"\"<\/p>\n

So I fixed it with what I had on hand. Almost 3500uF at mostly 25V (I also added some low-value SMD on the other side). The high-voltage cap I added is only 2.2uF at 400 (the one that was on there is marked “10uF 400V” and it’s the smaller of the two).<\/p>\n

* For the record, all six ports are in parallel. All have the same capacity. Which might<\/em> be 2.1A for all six combined**.
\n** There is provision for USB-PD resistors, but they are also not fitted.<\/p>\n","protected":false},"excerpt":{"rendered":"

Earl Munz was a 1940s salesman who realised that about half the components in the television-sets-du-jour were only needed in edge cases, and he (correctly) reasoned that there was a lucrative market in the middle. Removing (“diking“) the “excess” components resulted in a cheap TV that worked well enough in the city. Reliability was actually improved, because fewer components. Yea well, that was then. This… is now. Here we have a USB power hub from the good fellows over at the Value Store. Chinesium AF. It lasted… surprisingly long. Maybe a whole six months in service. Whoop whoop. Note the...<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[75],"tags":[],"class_list":["post-6115","post","type-post","status-publish","format-standard","hentry","category-electronics"],"_links":{"self":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/6115","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6115"}],"version-history":[{"count":9,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/6115\/revisions"}],"predecessor-version":[{"id":6128,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=\/wp\/v2\/posts\/6115\/revisions\/6128"}],"wp:attachment":[{"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6115"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6115"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.retro.co.za\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}