Kitchen Table Electronics Repair - "The Wrong Power Supply"

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Kitchen Table Electronics Repair - "The Wrong Power Supply"

Рет қаралды 47,009

Күн бұрын

Using an incorrect power supply with the wrong voltage, current type or polarity can instantly ruin an electronic device, possibly beyond all repair. That's what probably happened with the Buffalo Technology wireless router shown in this video.
In simple terms: one BZZZZT! and it's probably too late.
Demonstrated in this video is the technique of developing a theory as to what went wrong based on surroundings and behavior of the router when connected to power. I also noticed that I could hear the Buffalo power adapter entering overcurrent protection whenever it was connected to the router.
In this case, the outcome is fortunate as the protection devices did what they should and in time to save the other electronics from any serious damage. The diode should be replaced to restore the reverse polarity protection. (It's quite possible that the diode just failed from age, but that I doubt considering the factors mentioned in this video and the fact that the antenna was also missing. It also seems doubtful due to the low operating voltage and current of this router.)
Yet these little routers aren't protected from everything, especially overvoltage. There is no protection circuit for that. A client of mine had the cable company out to work on their equipment and power adapters for the modem (12 volts) and router (5 volts) got swapped. The modem simply didn't work, and the router was toast, probably within seconds.
What can you do if you a have a device for which you don't have the power supply? Sometimes you can make an educated guess as to what is needed by looking at the area where power comes into the unit. The polarity and voltage ratings of capacitors, arrangement of board traces, presence of rectifier diodes or a packaged rectifier, or even a voltage regulator IC/circuit may all give ideas of approximately what the operating voltage and current type (AC or DC) should be. Simple devices (like a tape recorder) with a motor or actuator may have voltage ratings printed on the motor or actuator. These may also be used as a guideline. So too can the number of batteries a device takes (often 1.5V x number of batteries).
A slightly riskier (but generally safe) technique on devices using a DC power supply (or batteries whose output voltage you can't determine) is to bring them the input voltage up slowly with an adjustable power supply until the device seems to work normally. It should then be observed to make sure that nothing is getting too hot or stressed in operation. This may also work on some devices that are intended to run from an AC input, but that's not guaranteed and definitely riskier.
And of course...sometimes a manufacturer actually prints the voltage, polarity and current requirements right on the device! Look around.
Be careful with the substitution of plug-in power transformers. While some are regulated and will put out the correct voltage (or very close to, as shown in this video) at all times, others are not and will put out a much higher voltage if unloaded or not loaded heavily enough. Test them using a meter set to the AC or DC voltage measurement scale as appropriate.
Tags: uxwbill kitchen table electronics repair buffalo whr-g54s router dd-wrt wrong power adapter used reverse polarity disaster damaged shorted diode protection device

Пікірлер: 119

@lysippus 11 жыл бұрын

understood. basically, any mismatch is bad any way you slice it.... the point of your video! thanks

@lysippus 11 жыл бұрын

would you say voltage ratings are more vital to the survivability of a mismatched power supply/power requirement than current? ie. if you have a 9v 300ma wall wart used in place of a 12v (x-ohm) power drawing item, would that prove fatal? as opposed to a 12v 1a wall wart/power drawing device? i guess my question is: do higher voltage wall warts plugged into lower voltage devices (ie voltage mismatch) cause more harm vis. a vis equivalent voltage wall warts with mismatched current draw?

@LightTheUnicorn 11 жыл бұрын

With the amount of adapters I loose and have to resort to universal switchable power supplies, this was pretty useful information ;)

@accordinglyryan 11 жыл бұрын

I have my WRT54G router setup with DD-WRT and for the past 6 months or so I've been lovin' it. I use it to connect computers without wireless to the internet. Works great.

@Lachlant1984 11 жыл бұрын

I know why manufacturers use off the shelf AC Adaptors that don't bear the device manufacturer's brand name, but I just think it's important for manufacturers to clearly label power supplies that are provided with their equipment. For example, AC Adaptor for use only with Buffalo Technologies wireless AirStation access point.

@GalaXy808 10 жыл бұрын

How about the diod did you replaced it? Or it's ok without it

@newtekie1 11 жыл бұрын

Conveniently routers of this class that can run DD-WRT are usually under $50 at this point, so if they get zapped they aren't expensive to replace.

@dogbyte555 11 жыл бұрын

Why not use the diode checker mode on the meter? Digital meters don't work well with diodes on the resistance scale. Of course a short is a short.

@Saaj2 11 жыл бұрын

We have those buffalo routers set up as bridges at school in the lunch hall for the pos and card system

@krist0sh 11 жыл бұрын

My friend and I was going to hook up a switch one time, and we managed to swap out the power adapter for the switch with the one for the modem. The switch power supply was 5V, and the modem power supply was 12V. The ovbious sign it didn't work was the switch sending out huge amounts of smoke, forcing us to open the windows. But it was a funny experience.

@Bandicoot803 11 жыл бұрын

Was that marshmallow being called "little heat spreader pad" the only thing that was patched on the microcontroller surface? No heatsink?

@Bleachanna 9 жыл бұрын

reminds me of the time i poured water into the vcr slot in a vcr tv, good times

@Lachlant1984 11 жыл бұрын

I know that more often than not electronic devices that include an AC Adaptor, the AC Adaptors usually don't bear the same branding as the device in question, but I do wish the device manufacturers would clearly label the AC Adaptors supplied so you could tell at a glance what it's used for. I remember one time we found an AC Adaptor at my Mum's house an none of us could work out what it was for, but eventually I realised that it was for Mum's Western Digital portable hard disk.

@bratina501 11 жыл бұрын

Then I heard a pop from the power supply and saw some smoke coming out of it and after this the telescope shut down. Unfortunately I did not know the current demand of the telescope when the motors were running and what happened was it pulled too much current and killed the power supply. The moral of the story is check not only voltage and polarity of the power supply but also the current demands of the device and how much current the power supply can handle.

@AintBigAintClever 11 жыл бұрын

A friend of mine did much the same thing with his Yamaha DX100 synth, plugging in a Nintendo 9V AC power supply. I repaired it (blown regulator if I recall) and fitted a bridge rectifier and cap so he couldn't kill it again :)

@itsJoel59 11 күн бұрын

So I don't need the diode to power it up?

@Qwakkeddup 11 жыл бұрын

Of all the leftovers I hoard that is one of the most difficult things for me, to keep original chargers and power supplies together and identifiable for any future use. It really kills me though when I have several power supplies, that are interchangeable, but they are all dead because they were all cheap junk that fell apart or failed for little to no reason.

@khroe 11 жыл бұрын

Yep, the old suicide diode trick, I have rescued a lot of "bad" equipment for this very reason.

@Jasonrotfl 11 жыл бұрын

My parents computer has the VIIV logo on it. It is an HP Pavilion something media PC, can't remember the exact model number off the top of my head but I know it has a Pentium D @3ghz. It was a pretty nice computer back in 2006.

@zx8401ztv 11 жыл бұрын

Thats smashing bill, you have another router for freeeeeee :-) Reminds me of the 1n4001 across the 12v input of c.b radios, ive replaced quite a few in my time as a radio repairer lol. The only problem with the diode is with the idiot that replaces the 2A fuse with a nail or typically a 35A fuse :-(, often the diode blows open and carnage to the rest of the radio is just too nasty to think about :-( Allways smashing to watch your vids bill :-)

@BulletMagnet83 11 жыл бұрын

I'm quite liking this channel so far! Subscribed.

@bratina501 11 жыл бұрын

It can not be just the device but the power supply its self and I have a story about that one. In the summer of 2004 I was playing around with a computer controlled telescope whose power supply was long gone and all that I had was a AA cell holder that held 8 of them which I knew to output 12 volts. Most 12 volt DC devices have a tip positive polarity which this telescope did and so I plugged the power supply into it. Everything worked fine until I tried to move it. (continued)

@mrsemifixit 11 жыл бұрын

Was that a Zener or regular diode that saved the day? I'm guessing regular in line and over voltage caused it to short to ground.

@Lachlant1984 11 жыл бұрын

Yes, I suppose that's true. I know the AC Adaptor that came with my Sharp MiniDisc recorder has something written on it about "For use with Sharp MiniDisc play/recorder only, Panasonic did something similar with the AC Adaptor that came with 2 portable CD players I've owned. With Apple AC Adaptors you can usually tell these days what they're for, but I just think the labelling should be a bit more widely standardised.

@CoolDudeClem 11 жыл бұрын

I must admit I'm being a little naughty with my modem and router, I have them both on the SAME supply together. But that's simply because I've run out of sockets to plug both supplies in so I just spliced the output of one of the supplies and put two connectors on it. It's all been running that way for a couple of years now and seems ok.

@Lukeno52 11 жыл бұрын

It's kids being kids, messing around and playing pranks. They could've done something far worse than this.

@1myk253 5 ай бұрын

Your a God for teaching this thank you. I need more help but thank you!!

@uxwbill 5 ай бұрын

No, I'm really just some guy with a camera, curiosity and a bit of knowledge. If you have an electronic device with a problem, there are numerous forums catering to diagnostics and repair. You can also post here with the details, if you want. Maybe someone will come along and help. Be sure to include the brand and model of what you're fixing. If your device has suffered from the use of an incorrect power supply, destruction of the device is an all too common outcome.

@1myk253 5 ай бұрын

@uxwbill I tried to fix a mamaroo circuit board. I couldn't find a ic or fuse on the board. I see you have mechanic and a.c. videos too. I hope to be like you one day. Thanks for replying:)

@vwestlife 11 жыл бұрын

"It should only have conductivity in One Direction"... that is rife for a certain Ft. Lauderdale cat sitter to make a joke about!

@vanderaj 11 жыл бұрын

Looks like KDE of some description, likely to be Kubuntu?

@robertherberg9595 8 жыл бұрын

I did the same thing the last time I moved. I got the speaker power supply mixed up with my 2TB network drive. You can't repair smoke.

@MarkTheMorose 11 жыл бұрын

I must admit that I recently killed a new little LCD monitor (sold on eBay as a car reversing monitor, intended to be used with my Raspberry Pi), by plugging in an AC adapter, instead of DC. I simply hadn't looked closely enough at the rating plate on the adapter. I opened the monitor up in case there was anything obvious that I might be able to replace, even in my relative ignorance of electronics, but everything looked fine. At least it wasn't an expensive lesson to learn (£20 / $25-30?)

@tttvn123 11 жыл бұрын

My Buffalo wzr-hp-g300nh has unstable Wifi function, very difficult or unable to connect, it get disconnected all the time. The wired function is ok. I opened the cover but most important area are shielded. Could you advise what is wrong with the router? What are common defect with Buffalo router? Thanks.

@DakalaShade 11 жыл бұрын

I know I should be asking this in one of your audio related videos, but I was curious, is there any safe way to de-amplify a receiver at the speaker jacks? I've got a set of nice speakers, but they're PC audio, internally amplified, and I wanted to use them with my home-theater setup. The problem is, stupid me bought everything with HDMI compatibility, and bought cheap, so there's no RCA jacks. I don't know much about audio, but I'm decent with electronics, if that helps.

@cgillyard 11 жыл бұрын

uxwbill, what OS are you using to test the internet connection on that router?

@tsun8267 5 жыл бұрын

How would I repair a keyboard that suffered reverse polarity? Its the Ducky shine 3 and when taking it apart the usb power source within can easily be switched and completely ruin the board in the process. Theres no schematic and tracing is difficult. I replaced two big capacitors that got hot when I ran reverse current through it again and two smaller capacitors that were also hot but it still doeasnt work. I used a thermal sensor and found 2 diodes that are a couple of degrees hotter than the rest of the board. Would I need to replace the diodes too?

@HeyChokiii17 11 жыл бұрын

i have a router that needs 9 v. but it does not work on my 9v adapter. i tried on my laptop charger which is 19v. it worked. what can be the problem? pls answer

@AndyD89 10 жыл бұрын

I am about (at long last) to buy a multimeter. I saw you used a RadioShack in this video, but I noticed you were using another (cheaper, I believe) brand when you were testing the fuses that blew and stopped the stove from working. Do you have any advice or recommendations based on your experience? I'm not going anywhere near high voltage (I'm in the UK with 240V mains power only), so safely isn't a concern.

@ankitpal9761 4 жыл бұрын

In my dlink router i plugged reverse polarity then resistor burnt !! What will i do now ?

@uxwbill 4 жыл бұрын

Replace it with another. The resistor is an effect, the cause likely lies elsewhere and in a part you probably cannot easily replace.

@cgillyard 11 жыл бұрын

Well Uxwbill, if you use a power supply not specified for the product, you know funny (bad) things happen.

@itsMatthu 10 жыл бұрын

Mine looks different than yours. Cant seem to figure out where the diod is.

@Bowowowification 8 жыл бұрын

+MelsonFritchie It's diode. What made you think it's spelled: "diod"?

@evanob89 9 жыл бұрын

Thanks for tutorial. I have a late model Linksys wifi router with a bad DC female connection on the back. I have to play with the plug and this invariably results in turning router on and off 2-4 times before the power will stay on. Any easy fix for this? I am using the OEM power supply. I have not tried opening unit. Plug feels like it seats in unit properly, but I have to pull it back slightly to get it to work. Thanks.

@evanobrien864 9 жыл бұрын

***** Thank you. I'll check that out.

@haz939 11 жыл бұрын

I've never seen a router to run only on 3.3v. I seen small travel routers use 5v. But nearly all use 12v.

@Grateful42 11 жыл бұрын

R.I.P my little wireless camera :[ I accidentally gave it 12v AC instead of 12v DC.

@bosejee 5 жыл бұрын

I have same model but not working only power light get on, and Broadcom chim getting heat up , whin i plug the adaptal cable eithernet light get on without pluging eithernet cable. it is repairable or dead

@uxwbill 5 жыл бұрын

It is impossible to say. As old as this model is, it is not worth repairing.

@cgillyard 11 жыл бұрын

I agree, that's what it looks like to me.

@ncrdisabled 11 жыл бұрын

I have 2 wrt54g with ddrt pro I just got a cisco duel range n router . Black Friday online 199.00 down to 40.00 and no rebate . Only could buy one otherwise I would have bought a few then sold them on craigslist. I also have 2 fon routers running fon firmware . The fon router have 1 problem 2 of them look exact same but 1 takes 9 volts and 1 5 volts . You could plug the 5 into the 9 worked until the router get loaded then fails . I wish they could be a standard

@DrRChandra 8 жыл бұрын

A dot at the end of a domain name can be helpful. It indicates the domain is complete (includes the root domain, "."), and suffixes should not be appended to it. As an example of appending suffixes, Time Warner Cable around here will send the suffixes "buffalo.rr.com" and "rr.com" in its DHCP offers, which, if you were to type just "www" into your browser, it might try "www.rr.com".

@cavisco 11 жыл бұрын

Can you do a video or series of videos on the DD-WRT firmware? Thanks, Scott.

@dcformee123 11 жыл бұрын

Bill I saw you have the radio fixed on your a station wagon can you send me the information where to send the radio I need to have my Lincoln's radio repairs

@itsMatthu 10 жыл бұрын

Put the wrong plug into it when I got it mixed up with another one while I was rearranging my workspace. When I plugged the wrong one in, it made a small popping sound. Now, when I plug the right one it, the buffalo does not turn on (like reviewed in the video) Should I try and remove the diod?

@itsMatthu 8 жыл бұрын

I ended up buying another one off eBay for cheap. Thanks for the thoughts though!

@kodienetanya8137 10 жыл бұрын

I put the wrong voltage adapter in an exercise bike and heard a popping sound. Dismantled it and found the wiring hub for the socket out. Plugged it back in still doesn't work. The batteries work for it but not the light is dim. Do you have any tips.

@DubNation2016 8 жыл бұрын

Could be a fried capacitor. Look around for one that's exploded.

@c9lb82 11 жыл бұрын

whered ya get the new dell? very nice machine

@coreyryan4876 7 жыл бұрын

if I have an ac-dc adapter that has opposite polarity of a device but same voltage output can I splice the wires and reverse them to change the polarity? trying to get my microKORG back in action. PLEASE HELP, AND THANK YOU!!!

@uxwbill 7 жыл бұрын

In theory, there should be no problem with doing this. Check the result and check it again just to be as sure as you can. The only other thing to look out for is voltage regulation. Not all power supplies are tightly regulated. Those that are just simple transformers with rectifier diodes may output a voltage twice (or more!) what is indicated on the name plate when they are lightly loaded (or not loaded at all). A lot of devices are fine with this, and the voltage would drop to the rated level as soon as any significant load appears. However, there are a few devices that need a tightly regulated power supply or they'll run the risk of being damaged.

@thnkbg 8 жыл бұрын

Can you help me? I ruined 2 expensive laptops being lazy & using the wrong power supply instead of buying the correct one on ebay.. one was a Gateway fx & the other was a asus rog i7.. I used the wrong power adapter because it fit & it powered the laptops for a while but little by little it became harder to connect. I had to twist & fiddle with it until it would finally connect.. then one day it wouldn't connect at all.. the supply was still good but the laptops wouldn't turn on at all... I'm hoping like you said its a protective fuse or something that burned out and can be replaced..... I can tear it down to the motherboard but I'm stuck after that as I dont know anything about testing or what to test nor do I have meters or Solder equipment.. My Question is how can I get the MB tested & whatever part that needs to be replaced done cheaply? should I take the MB to a electrician? can I send it to you? Whats your best advice? Is there an exact video you can refer me to that has the exact laptop problem as I? thanks.

@uxwbill 8 жыл бұрын

+thnkbg In most cases, if you had used a power supply with sufficiently different characteristics from those required by the device you wanted to power, the results would be spectacular and instant failure, especially for situations of reversed polarity. A power supply that was only slightly out of specification might result in delayed damage taking place, but that is much less common. (Slightly too high of an input voltage may take a long time before it triggers a failure in the equipment being powered. A power supply that's too small for the load being powered will usually suffer voltage sag, may eventually overheat and could burn out if the overload is big enough.) I think that the problem you have was caused by mechanical differences between the correct power supply and whatever you used. That is to say that the barrel connectors was perhaps not of the correct size (inner and outer diameters) and that over time it damaged the laptop's power connector. Solder connections holding the connector to the motherboard may also have been cracked or broken. More likely than not, the only part that needs to be replaced is the power connector itself. Damage to these connectors, usually through some kind of trauma such as someone tripping over the power cable while it is plugged in to the laptop, is very common. There are lots of places that offer such repairs. The going rate is around $100, give or take. This isn't the kind of thing that most electricians could help you with, and I don't operate a professional repair service. If you feel the repair cost is worth the money, I would recommend looking up "laptop power jack repair" specialists in your area. And after the repair has been done, get the right power supply! This isn't a good project for a first time repair, especially if you're not equipped and experienced enough to do it.

@thnkbg 8 жыл бұрын

+uxwbill thanks man... If its a daughter board with the DC jack already on it or a pig tail type of DC Jack, thats easy to replace but If its a Solder Job I gotta send it out.. thats again buddy.. you the man..lol

@JoshuaWagner 11 жыл бұрын

DD-WRT is the best!

@MegaMobass 11 жыл бұрын

awwww dangit bill!!! you sure zapped my hopes of first

@faizatoseef2379 6 жыл бұрын

Can u help me i m from pakistan i just put my ninja blender s plug that is 110v into the 220 v wrongly now my blender is just dead not working plz tell me is it repairable or not thanks sir

@uxwbill 6 жыл бұрын

Sorry, no. I don't know anything about Ninja blenders. Mistakes like this are very often fatal to motor and transformer windings.

@Desmaad 11 жыл бұрын

So, I take it you have a Windows PC and a Mac as well?

@marwaahmed8928 10 жыл бұрын

can anybody helpme to know what happens if i entered 9v adaptor in 5v device just for 5 sec

@Acc0919mc 11 жыл бұрын

I did this once whaen i was little. i plugged in a random charging cord to a wireless vacuum and the batteries overheated and got extremely bloated. melted the plastic and everything

@kapepe9248 6 жыл бұрын

hello sir, i have a problem to my router hauwei e5172. i install a wrong battery to my router. when install i turn on the router after 2 mins the power light indicator turn into pink. i remove the battery and i put the original power supply after turning on the power all lights indicator function well after 2 mins the power light become pink and all lights is off. can you help me to repair my router

@uxwbill 6 жыл бұрын

No. Using the wrong power supply or battery is all too often fatal. Since it seems that your router still tries to power up, I suspect a software problem. I don't know anything about this hardware, so I cannot be of any further assistance.

@kapepe9248 6 жыл бұрын

😞😞😞😞

@iggy151 11 жыл бұрын

DD-WRT ROCKS!!!

@DesslokX 10 жыл бұрын

du to electricity blackout, we are forced to use 12V/7A batteries to connect to the internet via our routers. One day, my gf accidentally reversed the polarity while connecting the router to the battery. we heard fireworks voices T_T i have the Cisco Linksys GWAG54G2... is there any hope ?? :( thx in advance

@hs_doubbing 10 жыл бұрын

Nice to know that I took out a Sega Master System by plugging the AC adapter tip in wrong...

@briceloy5071 11 жыл бұрын

Hey bill when are you gonna make another computer vid? By the way I was gonna by a CDS compaq presario but it has some issue like a falty hdd

@lmull3 11 жыл бұрын

don't taze me, bro!

@HDXFH 11 жыл бұрын

Looks like a PC desk :P, maybe a regulator got popped?

@Lukeno52 8 жыл бұрын

I have a laptop that appears to not actually care what kind of voltage I feed to it. Voltages too low or too high, it still runs fine (it's supposed to run at 20V, but I'm pretty sure I ran it at 16V and 22 or 24V.) I wouldn't run it at the wrong voltage too often, and I only did these by accident (universal charger and forgot to check the voltage)... but it was amusing nevertheless.

@uxwbill 8 жыл бұрын

While I certainly don't advocate such, a lot of laptops won't be too picky about the incoming power supply voltage, so long as the polarity is correct. Most of them immediately regulate the incoming voltage further with a DC-DC converter.

@tylersywyk8152 7 жыл бұрын

is there another way that I could contact you?

@amberlynn6914 11 жыл бұрын

ok. but still, that's kind of odd.

@lindakang2069 8 жыл бұрын

Can plugging my router into a wall with a bad wifi connection kill my router?

@uxwbill 8 жыл бұрын

I don't know what you are asking.

@lindakang2069 8 жыл бұрын

I think there's something wrong with the wall in my apartment. My roommates and I have bought two routers and where we plug it into this wall they all suddenly stop working. It's the kind of place where you just plug the router directly onto the wall and you don't need a modem. I want to know why they stopped working all of a sudden.

@uxwbill 8 жыл бұрын

I cannot tell you for certain. I would highly recommend consulting with your landlord or hiring an electrician yourself.

@amberlynn6914 11 жыл бұрын

Who sets the password as Password?!?

@GalaXy808 10 жыл бұрын

Thanks

@leonmilvets4089 11 жыл бұрын

Nice Video Bill :-)

@TheFlyingScotsman 11 жыл бұрын

Fantastic!

@novachevyguy 11 жыл бұрын

u wanna sell it???

@lindakang2069 8 жыл бұрын

We've pluggled two different routers into this wall and they both stopped working,

@uxwbill 8 жыл бұрын

My suggestion would be "do not plug any more routers into whatever you've been plugging them into". Exactly what you are plugging the router into is not clear. Please be more specific. It is *vitally* important to be sure that you are matching the polarity, current type, output voltage and current rating to the equipment you have. Otherwise you will continue to burn out other wireless routers if you are using the incorrect power supply.

@lindakang2069 8 жыл бұрын

I'm not sure if it's the wall regular electrical connection or the ethernet cable wall connection.

@uxwbill 8 жыл бұрын

I would suggest having your landlord examine both. Either that, or hire an electrician to test the wiring. Also, as previously indicated, be sure you have the right power adapter for these wireless routers. If you use the wrong one, it could ruin the wireless routers.

@lindakang2069 8 жыл бұрын

The router is not completely dead the light still turns on, it just does not give off wifi anymore.

@uxwbill 8 жыл бұрын

You can try to reset the router to its factory defaults. On most routers there is a small round button that you would press in and hold for about 30 seconds. Be sure the router is plugged in, turned on and has had a minute or two to start up before you do this. I would still strongly recommend that you consult with an electrician or your landlord to determine the problem.