Laptop power supply for $4 ???? wt - Page 1
Forum section: electronics / general

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 15, 2015, 05:55:00 pm
content: I remember buying not too long ago one replacement power supply after another for my laptops, and they were usually about $70 at jaycar. The last one was a lot smaller than the rest, but still expensive.But I can't believe this, there are power supplies suitable to put ends on and run the laptop from 12v or a car for $4 !!http://www.ebay.com.au/itm/New-150W-Boost-Converter-DC-DC-10-32V-to-12-35V-Step-Up-Module-Voltage-Charger-/391203833868I thought people who are in a similar situation might like to know.

author: mmagin
author_rank: Frequent Contributor
timestamp: August 15, 2015, 07:40:58 pm
content: Well, there's no enclosure, no isolation (may be fine in this application).And at that price, I would certainly expect the electrolytic capacitors not to be as good as anything name-brand, and I would expect build quality issues (solder joints, thermal coupling between transistors and heatsink, etc.)Aside from that (and the unimpressive specs), I see nothing wrong with it

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 16, 2015, 04:21:58 am
content: Quote from: mmagin on August 15, 2015, 07:40:58 pmHmm, old one cost $70, new one costs $4 should I buy 12 backups or 15 just in case. Oh yeah, and STILL save money compared to Jaycar.As for Quality, considering how many FAILED JAYCAR ones I went through, China has NO competition.

author: Psi
author_rank: Super Contributor
timestamp: August 16, 2015, 04:23:24 am
content: i bought one of those to have a play. Haven't had time to test it out yet.

author: ez24
author_rank: Super Contributor
timestamp: August 16, 2015, 04:36:51 am
content: I have bought several and so far no problems. I run them to the point the heat sinks are too hot to touch. I am driving mine from a laptop ps at 19v in.

author: tooki
author_rank: Super Contributor
timestamp: August 18, 2015, 09:46:17 am
content: Quote from: TheElectricChicken on August 15, 2015, 05:55:00 pmMaybe I'm missing something, but I don't see what part of that makes it a "laptop power supply" (a term normally understood to mean the brick that goes between mains and the laptop).As for chinese power supplies in general, I'd be leery of them on any device that uses a touchscreen or touchpad/trackpad. Those devices use capacitive sensing, and are extraordinarily sensitive to dirty power. Bad power makes the touch sensors misbehave.

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 18, 2015, 10:18:16 am
content: Quote from: tooki on August 18, 2015, 09:46:17 amThat's WHY I'd buy a Chinese one, because they are the best. Did you even read my message about how many $70 supposed top quality ones died in the ass ? I can go collect some of the dead ones I really wish I'd kept them all now, put them in a pile. Take a picture and post it. I could have bought quite a few new laptops for what those expensive name brand power supplies cost. Give me cheap chinese crap, just because some rich moron owns the tv channel and agrees with the other rich morons who own channels that they'll all badmouth the chinese, what ? do I care what rich assholes think ? they can shove their TV channel ..... Ah, I should slow down. PUT it this way. $4 and I'll put the rest of the money towards a new better laptop and profit. Chinese ? Oh gawd yes. Give it to me every day of the week. Chinese food, is there any better ? no. There is everything to be said for Chinese, I don't give a flying fart what some rich bloke's TV channel says. Leave it to the parrots to parrot it and be brainwashedand as forQuoteThat is NOT a review. That is NOT a lab test, that is NOT even a link to anything that looks anything like any of those. That's by the dictionary prejudice which I suspect has been caused by too much TV!! Less TV more real world scientific testing please !QuoteYeah, the part where I visit dead laptop power supply mountain and return from my trek with the leads that go between laptop and 12v cigarette lighter socket.

author: Unknown
author_rank: Unknown
timestamp: August 18, 2015, 12:05:51 pm
content: Quote from: TheElectricChicken on August 18, 2015, 10:18:16 am(emphasismine)Hang on, didn't you say you bought them at Jaycar? The guts of the $70 supply are probably cheaper & nastier than your $4 ebay special. Gotta keep Gary in ... anyone know what he's flying / driving these days?(Don't get me wrong - I give Jaycar props as one of the few remaining B&M electronics hobby retail stores, and Gary can do whatever he likes with his money. But let's face it - much of their stuff is dx/alibaba quality or lower, and at least an order of magnitude more expensive. That's just a fact of the fecked-up retail environment in Australia.)

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 18, 2015, 12:18:32 pm
content: hmm, I said..

author: tooki
author_rank: Super Contributor
timestamp: August 18, 2015, 07:42:06 pm
content: Quote from: TheElectricChicken on August 18, 2015, 10:18:16 amI seem to have caught you on a day where all your crazy came spilling out. I will agree with you about Chinese food being awesome, though!Quote from: TheElectricChicken on August 18, 2015, 10:18:16 amNot prejudice. It's documented fact. (The fact that I've anecdotally seen those problems with clients is secondary; plenty of scientists have actually tested and quantified this, and the fact that good quality manufacturers design their PSUs to avoid this shows that it's a known, measurable thing, not just "prejudice".)http://www.epanorama.net/newepa/2013/03/12/touch-screens-and-charger-noise/http://www.edn.com/design/sensors/4411529/Aggressively-combat-noise-in-capacitive-touch-applicationshttps://support.apple.com/en-us/HT203171https://www.westfloridacomponents.com/blog/noise-affects-touch-screens/http://www.silabs.com/Support%20Documents/TechnicalDocs/Minimizing-Touchscreen-EMI.pdfOh, did I mention that I seem to have caught you on a day where all your crazy came spilling out?Quote from: TheElectricChicken on August 18, 2015, 10:18:16 amSo you're using a DC converter with a laptop. Whooptie-shit. That doesn't make it a "laptop power supply" any more than using a rusty nail to poke a hole through one's lip makes that a "body piercing needle".Also, did I mention that I seem to have caught you on a day where all your crazy came spilling out?

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 19, 2015, 06:17:12 am
content: Quote from: tooki on August 18, 2015, 07:42:06 pmThat would be every day of the week for me, which day is it for you ?QuoteApparently that day is today.

author: mikerj
author_rank: Super Contributor
timestamp: August 19, 2015, 05:45:30 pm
content: Quote from: tooki on August 18, 2015, 07:42:06 pmWestern "Chinese" food is lovely but nothing like real Chinese food. I wonder how many people have actually eaten at a restaurant in e.g. Shenzhen? They appear to take a chicken, remove all the tasty looking meat and then serve the carcass. If you are really lucky the tougher bits of gristle will be deep fried and look quite appetising until you break your teeth trying to eat them. You also get the complete chickens head served up as a delicacy.I had a crunchy frog stew whilst I was there, literally whole frogs that were like little leathery bags of skin with small crunchy bones inside. Fortunately it was so heavily laced with chilli peppers that I couldn't actually taste anything else.To be fair some Chinese food such as dumplings and most of the vegetable dishes are delicious, but there are a lot of dishes that the average westerner would probably spit out if they tried it.Top tip: don't go to McDonalds in Shenzhen unless you believe burgers are supposed to be a light grey colour. By far the worst meal I experienced over there, and it went into the bin after the first bite.

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 19, 2015, 06:21:53 pm
content: Quote from: mikerj on August 19, 2015, 05:45:30 pmAh, same here in Australia.

author: neslekkim
author_rank: Super Contributor
timestamp: August 19, 2015, 06:34:53 pm
content: McDonalds isn't food..But rumors has us to believe that Taiwan is the place to test McDonalds:http://www.mirror.co.uk/news/world-news/mcdonalds-goddess-becomes-viral-hit-6252164

author: mazurov
author_rank: Frequent Contributor
timestamp: August 19, 2015, 06:40:09 pm
content: In my experience, good laptop supplies start at US$10. I actually opened a couple to see how good they are and found them adequate for the task of providing 50-100W of power for long periods of time. They are also good for driving random homemade LED fixtures.

author: TheElectricChicken
author_rank: Frequent Contributor
timestamp: August 19, 2015, 06:56:17 pm
content: Quote from: neslekkim on August 19, 2015, 06:34:53 pmagreed. If people think of McDonalds as a place to eat, they obviously haven't thought hard enough. I interrogated someone about their choice once, they claimed there wasn't anywhere else close, yet had to drive past fish and chips, Thai, Indian, and others to get there.QuoteThe smaller bottom of her face and big eyes make her seem very youthful. She'd be very very popular in Japanese media, they really go for the lolita look (or lolitas) and the anime look. She'd be a big hit there. Gotta wonder why she'd waste time at McDonalds.