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1. Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 06:58:52 JST Foone🏳️‍⚧️

   My roommate's LED lights went out, and she traced it down to a bad wallwart. I thought I'd crack it open and see if there's any (electronic) gore.
   Nothing on the trace-side of the PCB, nothing seems to have gotten super hot and burnt, unlike that last power supply I opened

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:02:41 JST Foone🏳️‍⚧️

     in reply to

     And the top looks okay too, except maybe that cap on the left that's clearly on the way out.

     (You may spot something else wrong. Hang on to that)

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:06:52 JST Foone🏳️‍⚧️

     in reply to

     It's hard to see in the photos, but yeah, that cap is definitely bulging.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:10:19 JST Foone🏳️‍⚧️

     in reply to

     And then I looked at the top of the plastic.

     HEY LOOK there's a cap. Or... the can for a cap?
     It's stuck to the top, with the electrolytic fluid I assume.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:12:06 JST Foone🏳️‍⚧️

     in reply to

     SO YEAH it turns out that weird brown cylinder you've been seeing in the pictures is the capacitor. It actually exploded the can off it, with the can getting stuck on the top of the case.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:14:38 JST Foone🏳️‍⚧️

     in reply to

     it's also possible this was always like this from the factory. Maybe this cap is just used for smoothing, and it being exploded just meant it did no smoothing. Maybe the other cap was doing the same, and that's why it ended up bulging?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:15:34 JST Foone🏳️‍⚧️

     in reply to

     yeah. my knowledge of how caps work is limited (I only took the first semester of EE) but it seems to be between the VCC and GND on the DC side

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:16:04 JST Foone🏳️‍⚧️

     in reply to

     so probably this thing was just outputting way less smooth DC than it should. Maybe the LEDs have their own caps, or maybe they just flickered like mad?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:17:50 JST Foone🏳️‍⚧️

     in reply to

     asking my roommate for updates

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:18:21 JST Foone🏳️‍⚧️

     in reply to

     • KING Calyo Delphi
     • petabites

     @HoustonDog @dragonarchitect sadly I'm anosmic, so I can't do the sniff-test

   • petabites (houstondog@mastodon.world)'s status on Monday, 09-Dec-2024 07:18:22 JST petabites

     in reply to

     • KING Calyo Delphi

     @dragonarchitect @foone
     
     I like to use sense-of-smell for boards like this (where something recently croaked)

   • KING Calyo Delphi (dragonarchitect@rubber.social)'s status on Monday, 09-Dec-2024 07:18:23 JST KING Calyo Delphi

     in reply to

     @foone I recognized it as soon as I saw it in the first picture~

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:19:32 JST Foone🏳️‍⚧️

     in reply to

     • Piggo :verified_horse:

     @piggo it's NUDE!

   • Piggo :verified_horse: (piggo@piggo.space)'s status on Monday, 09-Dec-2024 07:19:34 JST Piggo :verified_horse:

     in reply to
     @foone you mean the cap that no longer has any can on it?
   • KING Calyo Delphi (dragonarchitect@rubber.social)'s status on Monday, 09-Dec-2024 07:41:05 JST KING Calyo Delphi

     in reply to

     • petabites

     @foone @HoustonDog Oofh, that probably also means a whole lot of foods taste extra bland to you, too. :c

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:41:05 JST Foone🏳️‍⚧️

     in reply to

     • KING Calyo Delphi
     • petabites

     @dragonarchitect @HoustonDog yup.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 07:42:37 JST Foone🏳️‍⚧️

     in reply to

     • loganer

     @loganer it looks like cloth to me, but I'm sure it's just some kind of paper

   • loganer (loganer@mastodon.social)'s status on Monday, 09-Dec-2024 07:42:38 JST loganer

     in reply to

     @foone that makes sense, it's probably some kind of old paper wax like capacitor...

     is it made out of cloth? though, intriguing.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 08:25:20 JST Foone🏳️‍⚧️

     in reply to

     okay amazingly, she says it never flickered and never actually died: it just got dimmer.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 08:26:47 JST Foone🏳️‍⚧️

     in reply to

     so my guess as to what happened:

     this cheap cap developed a partially short. It now began passing current through it. This caused it to heat up, boiled the electrolyte, and exploded the can off.

     The thing STILL keeps working because now that it's dry, it's a really shit conductor, so only some of the current is going through the sploded-cap, which can no longer boil (and it doesn't get hot enough to ignite). But since some the current is diverted, the lights dim

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 08:40:24 JST Foone🏳️‍⚧️

     in reply to

     I would test the resistance (and capacitance) of this exploded cap but I don't have access to my electronic tools at the moment. so into the ewaste bin it goes

   • ParzivalWolfram (parzivalwolfram@infosec.exchange)'s status on Monday, 09-Dec-2024 08:47:09 JST ParzivalWolfram

     in reply to

     @foone act-of-god your way into a FREE 300 ohm resistor!

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 08:47:09 JST Foone🏳️‍⚧️

     in reply to

     • ParzivalWolfram

     @parzivalwolfram 300 ohm resistors are cheap anyway if you own wires

   • Rue Mohr (ruenahcmohr@infosec.exchange)'s status on Monday, 09-Dec-2024 08:58:52 JST Rue Mohr

     in reply to

     @foone

     https://x.com/RueNahcMohr/status/1266519992125648896

     sorry, but... really.... I know you have a scope.

     http://ruemohr.org/~ircjunk/circuits/captester.jpg

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 08:58:52 JST Foone🏳️‍⚧️

     in reply to

     • Rue Mohr

     @RueNahcMohr I do, but I can't use it right now. I'm mostly bedridden for medical reasons, so my electronics workshop is unusable

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 11:18:41 JST Foone🏳️‍⚧️

     in reply to

     • Medea Vanamonde

     @MedeaVanamonde nope! apparently it ran like this for quite a while

   • Medea Vanamonde (medeavanamonde@chaosfem.tw)'s status on Monday, 09-Dec-2024 11:18:42 JST Medea Vanamonde

     in reply to

     @foone did it catch fire

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Monday, 09-Dec-2024 12:34:12 JST Foone🏳️‍⚧️

     in reply to

     • evin

     @yujiri I think that's resin/glue to keep the thin wires of the transformer from getting damaged, or possibly arcing to nearby components

   • evin (yujiri@freeradical.zone)'s status on Monday, 09-Dec-2024 12:34:13 JST evin

     in reply to

     @foone what's the blobby thing that looks like a chicken breast?