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Fixing a wall-wart?

Hi, I have a wall-wart that is working but I'm having some problems with it. It coverts 220AC to 10VDC with 1,3A current. I've been using it mainly to power up 8cm PC fans. Recently I opened it up and saw that below the diodes,board has turned black and it seems fried, that can be from excessive heat generated by diodes, and part of the transformer that was facing this diodes is melted (as you can see in pictures). I think diodes are 1n4005. 1- my first questions is, why these diodes got this hot ? should I change them with diodes that can pass more current?  I have RL205 will that work? 2- I've read somewhere that after rectifier bridge, if capacitor's capacity is high, it will put pressure on diodes and transformer, is this true ? or we can use any high capacitor we can find ? 3- Is there a law by which we figure out how high our capacitor should be after rectifier bridge in wall-warts ? for example If I had a wall-wart with 1000mF capacitor, can I change it to 2200mF ? 4- I am going to use this wall-wart to power up a 7805 regulator, so that I can feed a lithium-ion battery charger module (4056). This module uses 1A. should I put a high value capacitor like 470mF or more, at regulator's input, or is it unnecessary cause of my wall-wart having a high capacitor ? 5- Are they any ways that I can improve this wall-wart ? like if I keep the transformer cool ,when it;s under load ...maybe add another capacitor ... ?

Question by ehsan_zt    |  last reply

Wall Wart question.....

I have an NCE cx12v500 direct plug in class 2 transformer in the form of a wall wart. I accepts the USA standard of 120 vAC in, at 60 Hz, and outputs 12 vdc @ 0.5 A. I thought this was the recharging unit for my portable drill, and so I plugged it in. After a few hours of charging, the drill moved but was sluggish. I unplugged it, and when I tested the output, it had dropped to around 1 - 1.3 vdc. I can't seem to find a way into the unit either (molded plastic) without sledge hammer or hacksaw usage coming to mind. Did I fry this one I think I did, but I am looking for a possible, no and solution from someone :-) Aaaargh ! I took it apart finally sawed a notch in it and pried it open... and there was #1: NO regulator *sigh*, and #2: NO fuse of ANY kind, and #3: just a tiny board with a 1,000 uF cap on it and 4 diodes (bridge configuration) by one I took components off and tested them with my VOMM and sure enough, all the components were good. Then I tested the transformer......and both sides should have tested closed or short, but one side (output) tested OPEN. *sigh* It fried the transformer ! :-(

Topic by Goodhart    |  last reply

Wall wart for digital camera

Hi everyone, I have a cheapo digital camera, a Norcent DC-1020. I've been trying so hard to figure out what kind of wall wart I need for it. It's rated at 3.3V and 2A, but here's what's confusing me, at the input it says "DCIN3.3V," which makes me think it needs a DC wall wart, but the sticker on the bottom says "3.3V [symbol] 2.0A max" where the symbol is two lines, one solid, one dashed. I thought that symbol was for AC?

Topic by burger_bot    |  last reply

wall wart/transformer instead of batteries?

I have recently purchased a creative HQ-2300D and it only accepts two AA batteries for powering the decoder, there is no DC in on it. Can I use a wall adapter to power it? (it really eats batteries)The intended charger, output is 3.7v = / 355mAhThe reason I am wanting to use a transformer with it, is it would make it a lot easier as it is only used for gaming on the xbox 360 (to get the dolby headphone from the decoder) so it is never used "on the go" so changing the batteries/ recharging them is a mild annoyance I wouldn't have from a transformer turned on when I use the 360. It can't be as simple as wiring pos to pos and neg to neg on the battery terminals inside the decoder with the nokia charger because there is only a slight variation in the voltage.....can it?. I am also concerned about whether the transformer is regulated or not, reversing polarity, correct polarity etc. etc. and what else is important not important when attempting to do such a thing, so as not to destroy my decoder. (I did this before with a minidisc player and a Universal adapter on the wrong voltage, I didn't impress myself..........doh.... anyone smell that....)I tried plugging the nokia charger into another 3v device (an old sony tape deck) that has a 3v DC in, and it didn't seem to give it enough power to turn the tape, but when I plugged in a universal adapter and set it to 3v it worked fine.My idea is to remove the fem connector from the phone and rig it so it can be plugged into one of the battery terminals and the nokia tranny can be plugged into it, but it can still be removed for when I want to use batteries.I put it to all those with the knowledge who can explain in lay-mans terms and educate me on the best, safest, cleanest way to solve my dilemma.Thanks.

Topic by py3m4n    |  last reply

power hack

Aside from it being an ugly hack, is there any reason I can't strip the wire back from the end of a printer power cable and solder it to the plug terminals of a 5v wall wart transformer? This shouldn't be a fire hazard since the power cord should be rated correctly, correct?

Topic by randofo    |  last reply

How do I wire these LEDs?

I'm need to wire 4 blue LEDs (3.4v) and 2 ultra bright red LEDs (1.9v), I would like to limit the current to 10ma and wire all the LEDs to a single wallwart. The wallwart I was planning on using is 12v DC 100ma. I'm pretty new to LEDs so I'm not quite sure how to do this, I was thinking about wiring the 2 reds and 1 blue in series and wiring the other 3 blues together in series and then wiring the 2 sets together in parallel. But I'm not sure if that will work because I read somewhere that if you're wiring in parallel all the LEDs must have the same voltage. So if anyone could explain how I could wire this up (and maybe even draw up a simple diagram) that would be great.

Topic by cannedham160    |  last reply

Powering multiple devices with different voltage using one wall wart.

I really hate to post such a remedial question here but after searching the better part of the entire weekend for an answer I'm not much further along than I was at the start. I even went as far as hauling my butt to the radio shack to ask them.... I don't know what I was thinking there... It's always been obvious to me the guys there don't know much more than how to push cell phones - not to say they are all like that but the one by me has never been any help in terms of electronics. Anyway, I want to power a 5mw (3 volt) laser and one PC cooling fan (9 volt?) from one spare 12v wall wart. I've never been much for electronics but I'm thinking I can run the power to a breadboard, then run 2 seperate feeds through various resistors and/or regulators... just can't get any straight answers as to the best approach for this.... what's the best way to cut the voltage to a safe level for each device. I'd be happy with a good instructable for something like this if someone can point me toward one. Thanks for your help!

Topic by feign3    |  last reply

Why do transformers have different power ratings? Answered

I've noticed that wall warts have different current output than others with the same voltage, is there a internal resistor in them? If there is, why; why couldn't they have just put it into the object they want to power? Or is it the actual transformer causing the power loss? -Thanks

Question by squirt8500    |  last reply

Why did my lm317 stop working?

I am building an lm317 power supply that has a 510 ohm resistor and a 10k potentiometer. For power I have a 12v 1A wall wart (really more like 14-15v ). I built it on a breadboard and then from there moved it to a pcb (the pre cut kind from radio shack) and everything went fine. However when I tested it before i closed up the project box, it would only supply about 14.06v to 15.22v. Im not sure what is wrong, all the connections look fine and nothing really changed from when it worked.

Question by tim127    |  last reply

Converting solar LED string lights to a wall wart adaptor.

Hi all I recently picked up some bargain priced solar string lights for room decoration and to provide a low level of light at night, I suffer from Meniere's disease and one of my triggers is moving around in complete darkness, unfortunately I also have problems going from darkness to light so simply turning on a light can also trigger an attack. I've tried all manner of different lighting but most were not suitable for a variety of reasons. A friend who is also a sufferer suggested LED string lights, the kind used at Christmas or to give some decorative lighting in gardens, he has similar problems with light and darkness to me and had been using them for several years he now has LED lights set into coving in every room of his house, I borrowed a loose string set of his he uses on some plants in a small conservatory while he was away on holiday and to use the same words I did to him on his return they were "Bang on perfect" bright enough to be able to move around comfortably (imagine a couple of candles in a bedroom) but not so bright that they keep me awake. I've had solar lights in the past and knew that the bargain price was probably because they had been in storage for some time so was not in the least surprised to find the batteries no longer take a full charge, I swapped out the old batteries for new ones but to be honest I bought them more for their look than the solar capability, I was originally seeking some mains ones but not wishing to have a hundred or more all I could find were solar or battery, I really don't want the hassle or expense of constantly replacing batteries and the solar ones come on automatically at night so it seemed a good compromise, unfortunately I'm still having problems, whether it's an issue of their not getting sufficient charge from the autumn sun to fully charge (the panels are stuck to my windows so are in full sun all day) or simply that the batteries are running down too soon they are just not lasting long enough for me to rely on them. What I would like to do is change the power to a mains wall wart, each string is powered by a singe AA 1.2v 600mAh battery and I'm hoping I can swap this out for a hard wired adaptor of suitable output. I'm not really an electronics/electrics guy, I can build wiring looms for motorcycles OK, I've made some simple additions to the circuits on my electric bike to power an alarm and installed 12v LED car bulbs into its lighting but that is all very simple low voltage stuff, I don't have much experience with converting from battery to mains. My questions are pretty straightforward and I'd like layman's answers, a whole lot of technical chatter about amps living in Ohms and suchlike will get me nowhere, all I want to know is is it a viable option and if possible where I could obtain the necessary adaptors suitable for UK 240v mains electrics online. These are the only tech specs I have on them that seem appropriate to my question are they are Solar Power: 2V 100mA If it's any help these are the lights in question. Thanks in advance for any help ideas and suggestions. NG.

Topic by Nostalgic Guy    |  last reply

Oldy transformer Wall Wart VS Swithing PSU more efficient? Answered

I mean whats the diffrence? I have bunch of the transformers and another bunch of the fully electronic kinds? why use one or the other? heat, efficiency, weight. BTW can i put a stepper motor to a 12v side of the transformer and maybe get some 110v on the other side or thats sounds crazy? thanks Al

Question by celalboz    |  last reply

How is it that I can measure voltage across an unplugged wall wart? Answered

I have a 9V wall wart that's been unplugged for 2 days.  I hooked it up to my volt meter with intentions of checking the polarity as I plug it in.  Without plugging in the wall wart I attached the meter leads to the exposed wire of the wall wart.  It immediately showed a voltage of -10 point something.  I was glad to find the wires were backwards which explains my fried regulator; however how is it that I was able to pick up a voltage, even after discharging it the voltage slowly rose again, unplugged!  Does this have anything to do with earths magnetic effects on the inductor?

Question by Dude Man    |  last reply

How do I power an UNO and two servos with a wall wart?

I have a project that I want to power with a wall wart (6v 2A). The project is a "Useless Machine", so it's not a complicated project. It uses 2 standard servos and one micro. I have searched a LOT, but I'm unable to find out how to properly do this because most projects use batteries. I know the motors and the UNO need to be powered separately. I thought I could simply splice and connect the 6 volts from the adapter to VIN, and also connect 6 volts to my servos, and tie the grounds together. And that worked for a little while. But then it quit working. Now I have >3 volts going to both my Arduino and my V+ line to servos unless I disconnect one. I honestly don't know which way to go at this point, so I'm reluctantly posting this question. I would appreciate any direction.

Question by Steve_Lane63    |  last reply

Will a 9v wall wart get real hot if i plug it to a lot of leds for 6 or more hours? Answered

I have this weird LED bar with the contacts soldered to the ends of an OLD 9v wall wart. its like 100 leds with some ICs and resistors connected to the power brick. The bar came from an old photocopier, i think its the part that illuminates the paper

Question by santy22    |  last reply

Specific output of current? Answered

I'm getting a little more knowledge about current measured in mA, but it's still all confusing. From my understanding, your project draws the current needed out of your battery. If my LED uses 25 mA, then the LED will be sucking 25 mA from the battery. If I have two LEDs, then it would be sucking 50mA from the battery, thus reducing its life. So, based on that, how can wall warts have a specific output of amps? How can a wall wart put out 1000 mA? If you use a project that only takes 700mA what happens to the other 300 mA? What if your project use 1,500 mA? And. . . How do you measure the current being pulled through a basic circuit and your average 555 circuit? Thanks,  

Question by HavocRC    |  last reply

12 2.4V lights in parallel, how do I wire it to a wall wart?

I have twelve 2.4V flashlight bulbs in some lovely ceramic fixtures that I have wired in parallel with quite a bit of 26 gauge solid wire (6" between each bulb and about 7' to the power supply). Despite them wanting 2.4Vs, 3Vs supplied with 2C batteries makes them only dim. I want to hook them up to a wall wart but I have had no success. 5V and 3V wall warts do nothing. I tried two others that worked for a while then burned out: AC Adapter INPUT: 120V ~ 60Hz 11w OUTPUT: 7.5VDC ===900mA MODEL: SCP48-75099 CLASS 2 TRANSFORMER AC Adapter MODEL NO: AD-091A INPUT: 120V AC 60Hz 15w OUTPUT: DC 9V 1Amp Condor I just got rejected from a juried show because it died as the jurors were looking at it.

Question by rebeccabbennett    |  last reply

Help with circuit to use either batteries OR a DC "wall wart" power pack.

I would like help with the type of circuit used in devices that can use either batteries, or a "wall wart"(AC to DC), or possibly even an AC cord if I decide to go that route (like a battery/ AC powered radio). I have a basic knowledge of electronics, but need help with this one. Is it very complicated? I'm not sure of specifics at this point, such as how many and what types of batteries (AA, AAA, 9V) what voltage, etc., just need to know how to build a circuit for this purpose. My project will use a single bright L.E.D, or possibly more, (maybe 3 watts each) and I would like to have the ability to plug it up if someone either doesn't have the batteries, or would just prefer to plug it up at all times. How does the device switch between battery and plug in? Thanks for anyone's time and help! I really do appreciate it.

Question by stevecinstrfme    |  last reply

I am needing an a adapter to convert 120VAC to 12VDC 8 Amps for a blower?

All the wall wart type adapters I've found don't seem to go above 3-4 Amps. And the only adapters I've seen that can handle 8 Amps are around $50. I can buy the $50 but I'm on a bit of a budget. Plus that's a lot of money in case I screw it up. I've only worked with regular wall warts before. So does anyone have any ideas or advice? (I'm going to be hitting some thrift stores today to see what I can find)

Question by DracoRincewind    |  last reply

Flyback driver, 555 timer and other transformer from wall wart. What transistor?? Answered

Hello people!  I recently got my hands on a flyback transformer (that is, I finally got over it and got it out of the monitor :p ) And I want to make a flyback driver. I already have a normal wall wart hooked up backward. I was thinking that I could connect the wall wart to the flyback and create massive sparks. Could I directly solder the flyback and the other transformer together? If so, what transistor would you advise to use in my 555 circuit in front of the first, normal transformer?

Question by dunnos    |  last reply

How to build circuit that would offer power by way of either a "wall-wart", or through batteries.

How is the circuit built that would allow a device to be operated by either a power pack ("wall wart") or through batteries. Like in so many toys it would be either/ or. It would automatically switch between one or the other, like, say you're out of batteries and still need this device to work, you can find either the power pack, or even direct ac. I have a radio for example, which I'm sure is like so many other devices of this nature, that can be plugged in (120 volt ac), or will work on the batteries. As soon as I unplug, it automatically switches to the batteries. Is there a circuit internally that changes the 120 volt ac to "wall wart" / dc voltage? Does anyone have a schematic for such a circuit. I don't have any specifics, other than the batteries being maybe 4 D cell batteries at 1.5 volts each (6 v). Thank you.

Question by stevecinstrfme    |  last reply

How can i possibly use a wall wart transformer in order to make an electric shocker? Answered

The transformer its self has 4 cables. Two of them were the high voltage input and the other two were the output(i am not sure because i took it appart a couple of time ago).  I also have a 5 cable transformer that was used by a battery charger.Two cables for input here as well and three for output(i also don't rememeber well for this one too). P.S please go easy on me because i am novice on electronics. Thank you very much.

Question by deathnoteviewer    |  last reply

Get rid of batteries on the Fisher-price swing to DC input

We bought a new swing recently and has been consuming 4 C batteries every week. I am wondering if can hook it up to Wall transformer. Any ideas? I have some wall-wart at home that output 6-9v. Can I use them? I can convert the wall-warts as per the instructions here: but do i need to change anything in the swing? and how to hook it up?Please advice ..Thanks

Topic by sulakhe    |  last reply

Mini AC-DC transformers?

Is there a device, such as a ready-made mini AC-DC transformer I can build directly into a project, so that I can connect it to AC mains... without a wall wart? I was thinking of taking apart a cellphone charger and just building it into my circuit, but it is not really the shape I'd like it to be... it's a lot larger than I would like. Flatter would be good...?

Question by micobanff    |  last reply

I may have fried my FlipHD camera with a 10V power adapter. Is it hopeless? Answered

I tried to power a FlipHD camera using a wall wart. Listed output was 3V, but on a meter, it turns out to be 10V. Camera doesn't work now.  Have I fried it, or is there a fuse or something that I can replace so I can fix it. Why does a power adapter list itself as 3V but output 10V?  Is this a cruel joke?

Question by DanYHKim    |  last reply

Multi-port USB power supply

My wife and I charge our tablets and phones in a central location.  There are so many wall warts and not enough outlets!  I would like to have a single USB type of power supply that can charge at least 6 devices at the same time.  Each port should be able to supply 5 volts DC at 1 amp or better.  I've purchased two different 4 port wall warts and they just don't have the juice to get the job done.  Any ideas?

Topic by Tgrshaw    |  last reply

What is this wiring diagram symbol? Answered

It's part of the power supply circuit and probably has something to do with the wall wart power supply, but I'm not confident enough in that explanation to move ahead with it.

Question by applesnacks    |  last reply

new instructable or just forum post?

I've replaced the battery on a portible drill with a wall wart. should i create an instructable or, since it isn't anything new as far as what i did, is it only worth a forum 'how to"?

Topic by jtobako    |  last reply

How can i make a dc power filter?

ive got a wall wart spitting out 10.5v dc, and i need to clean it up, as it is going to a psone screen.

Question by clark    |  last reply

How do you make sodium chlorate? Answered

I want to make some sodium chlorate.Is there any way to make it?I have heard there is some way to make it through electrolysis.I have a wall wart.

Question by bylerfamily    |  last reply

Questions on the Building the Power Supply

Does the wall wart need to be AC or DC. Also how does the potentiometer go in the circuit? I bought a 10k volume potiemter here:[] Will this work?

Question by jfrazi10    |  last reply

Simple Laser circuit problem? Answered

I connected 6 fully built laser pointers (minus the battery compartment) in SERIES with alligator clips. They each draw around 3v and 300mA (they are those cheap 5mw green pointers). I connected the end leads to a 19.5vdc 4.5A laptop wall wart power supply. I taped all of the laser buttons into the ON position. Aannnd...   ...nothing happens. The lasers are fully functional when using batteries, yet when wired up in this way there is no light. What is wrong with this setup? Thanks EDIT: I can also garuntree that all connections are perfect, and there is pleanty of voltage and current coming from the wall wart.

Question by madman11    |  last reply

best way to cut PET plastic bottles? #1 recycle triangle Answered

I want to improve the usb,wall warts,,technical cord storage trick that i think i saw here.they were using a toilet paper  tube.  i noticed that a lot of smaller Gatorade type PET bottles would work nice, since they are clear, and stronger.  i used scissors to cut some and get ragged edges, which i could fix, but i was wondering if a hot wire,like a styro? foam shaper would work better ? with the plus of smooth edges 

Question by escapefromyonkers    |  last reply

How to create a DC power supply filter? Answered

I am programming a microcontroller, and it worked fine. By this time, the microcontroller is powered by the USB port. After programming, i do some testing, i used LM7805 paired with wall wart as the controller's power supply. When using this power supply, the controller's behavior is a little bit unpredictable. Based on observations, the problem is the ripple in the DC supply. I there a filter method or topology that i can use? Note: simple capacitor filter won't work. i have a frequency counter... it reads 0 Hz at the USB and reads 60 Hz at the LM7805 powered by a wall wart.

Question by codestroy7    |  last reply

How do computer power supplies convert wall power to logic-useable power? Answered

Although I have some fair experience with electronics, it has all been battery-powered. I know that a transformer can step wall voltage down, but in doing so raises the amperage, correct? I know that the forward current limit on a 555 timer is lower than most wall-wart tranformers supply, and therefore lower than what a power supply can supply? Thanks!

Question by mad magoo    |  last reply

Why is my iPod amplifier circuit fuzzy? Answered

I used an LM386 audio amp with its usual circuitry to amplify signals from an iPod headphone jack, but the sound quality is terrible. I have tried powering the circuit with a nine volt battery, and with a wall wart, and, although sound quality was better with the battery, it was still pretty bad, and not very loud. I have tried different LM386 chips, and a speaker that I know is of decent quality, and the sound is still bad. I have also used a filtering capacitor in series with the decent speaker, and the quality was okay, but the sound was very faint. Sometimes with the wall wart I got a weird buzzing noise, and with either the battery or the wall wart I often get unpredictable gain from the amp and bad sound. My speakers are around 2-21/2 inches in diameter, and around 10 Ohms, and the decent speaker is of unknown dimensions and around 9 Ohms. I also tried one of Kipkay's homemade speakers, and, no offense Kipkay, but it all went badly after that, probably because my homemade speaker was only 4 Ohms, when it should have been 8 ( The speaker is not Kipkay's idea, he credits it to Jose Pino, from Make Magazine, vol. 12). I'm also using generic 24 guage wire, not speaker wire, could that be the problem? Please help! Thanks! P.S. I tried to make one of those big LED's sync to the music, but ended up burning it out with the wall wart, will the smoke hurt me? Thanks!

Question by mad magoo    |  last reply

How to power LED Strip Lights that have been cut into sections?

Hi Guys I bought a 5m reel of white 3528 leds a while back and now have a use for them.  I'm going to run a strip under my desk and then another circuit around a shelving unit.  The lights came with a 12v 'wall wart' to power the whole strip.  However, I'm going to be cutting the whole 5m strip into three separate circuits.  Can I still use this 12v adapter on one of the sections?  or should I be looking for a lower powered 'wall wart'? Would appreciate some help on this.  Not my usual area of expertise.

Topic by wizer    |  last reply

How to Determine Current (amperage) Draw for LED Strips

I have some warm white solid color LED strips. The packaging doesn't say anything about their current draw (neither amperage or "watts"). The strips themselves are marked as 12VDC. I want to use a wall wart to power a strip of lights but I think I need to know how many amps they will draw in order to select the right wall wart.Is there any way that I can find out the current draw either online or by using a multimeter?For example, I have a wall wart that converts 110-120VAC to 12VDC that is marked for 5 amps. I don't want to overload the circuit and create problems but without knowing how many amps per foot the LED strip draws, I'm reluctant to make an installation.I'm uncertain that I'm even asking the right questions. I'm just learning a little about electricity and electronics (Thank you, randofo) by taking classes here. I've learned in my 7-1/2 decades of life that a little knowledge can be a dangerous thing; so I'm asking help from the cognoscenti at

Question by Cueball21    |  last reply

Popular 2 pin power connector for PCBs?

I have made a prototype PCB board which requires connection to a 9V battery or a wall-wart. The board is very small and doesn't have much extra space. I'm currently using a female header(as used in arduino) with 2 pins broken off into which I'm plugging in the wires from battery. In the final board, I want to be using some connector which is widely available, and PCB friendly. The one which I have most commonly seen being used is the wall-wart female power jack which is way too big for my requirement. Any popular option which is only slightly bigger than a snipped female header? -Antzy

Topic by Antzy Carmasaic    |  last reply

Power 30 3mm LEDs (from battery powered string lights) with 5V 140mA wall power block? Answered

I have a string of 30 3mm LEDs attached to a battery pack which holds 3 C-size cells and has a switch, and a 10ohm 10% resistor (brown black black silver). I'm not sure of the exact specs for the individual LEDs, but they look pretty standard (warm-white, 3mm.) I think they are connected in parallel (2 wires in to each, 2 wires out) I also have a power block (wall wart) from an old vacuum which outputs 5V DC 140Ma. Is it possible to power the LED string with the power block, and if so, what kind or resistor should I substitute for the original? (and, for future reference, how did you arrive at your answer?) How does supply wattage matter? Might as well throw this in as well: what resistor would I need to power them with USB?

Question by Vick Jr    |  last reply

Supplying amperes on fan? Answered

Hey, I'm just wondering if I were to plug in two fans rated at 12V .1A to a 12V 1A power supply, would the extra .80A will overload out the fans? Or will the fans only draw what it will need? And for other simple devices like LEDs, will this apply?

Question by BIO Wolf    |  last reply

AC power source for a blinking LED ?

AC power for a blinking LED ? can I  power....a  single blue flashing LED (3v-3.5v, 25MA?)....from an ac power source like cell phone charger or wall wart.....for continuous use without any problems? thanks

Question by garydalef    |  last reply

What type of transformer is this?

I got this out of a wall-wart and am trying to add it to my stun baton to make a bigger arc, can anyone tell me the full info on how to use it as an arc generator using a 2000 volt input?    PS im doing this safely and DO NOT USE THIS ON LIVING THINGS JUST AN EXPERIMENT!!!!

Question by Myers Technology    |  last reply

Current Draw for 178 RED LED's @ 20ma each. Is this really going to require 12vdc 3560ma power supply?

Want to be sure before I purchase AC/DC Wall Wart. I was thinking a 1000ma supply would be ok. I'm I wrong on that or I'm I missing something.

Question by keydogstony    |  last reply

How to run a single LED from AC current?

I've been reading up on a lot of existing posts and projects about people wanting to power LED(s) off of 120VAC. Most of the suggestions I see refer to the use of a wall wart DC power adapter to accomplish this task. In many cases, it would probably suffice. However, due to a very limited amount of space I have to work with, I need to make this project as thin as possible. I really don't have the room to accommodate a big wall wart adapter. Can anyone direct me towards being able ot make a single LED run off AC? I'd also like the ability if possible, to run it with a photo sensor to turn on/off night/day. Thanks! Dustin

Question by djc311    |  last reply

Arduino getting really hot? Answered

While running one of my projects, my Arduino is getting really hot. It's swtiching somewhere around 14 I/O's really fast (im not sure exactly how fast, but its refreshing somewhere around 2.5 milliseconds each time). The chip gets really warm, and to burning hot in about 20 mins. The project runs fine (I've tested for at least an hour, with no ill effects) but Im just wondering if its normal and/or safe. Also the voltage regulator chip gets really hot if i run the same sketch with a 9v wall wart rated at 350 ma, and also with a wall wart rated 7.5v at 2.14 A (the v-reg on the arduino board doesnt get hot if i run it off USB). Should I be concerned? -Astroboy907

Question by astroboy907    |  last reply

Need help with a circuit. Answered

I want to make a circuit that lights up 14 LEDs in parallel. The LEDs require 3.2 volts and 20mA each. If I use a wall wart that supplies 9v dc and 350mA, What resistors will I need and how should I connect them? Also can the current blow my circuit?

Question by    |  last reply

I want to replace the 4xAA battery pack in my camera flash with wall power. Can you help?

I want to replace the 4xAA battery packs in my camera flashes with a wall wart power brick. How would I do that? I think I need at least 6v DC but I am not sure on the amperage. Any ideas? I figure i can make a "plug" to replace the 4xAA battery pack so that I can use both when ever I want to swap. Any ideas? Thanks! Andrew J

Question by drewman21    |  last reply

Amps for 12 volt tire inflation pump

I'm trying to attach an AC adapter to a 12-volt tire inflation pump (the kind that plugs into your car's cigarette lighter), then convert it into a vacuum pump for degassing molds. I tried connecting the only 12 volt wall wart I have and it just barely got the motor moving. I'm guessing that the amperage of the adapter is too low. What sort of amps would this unit need to run correctly? Is it even possible to run this thing from a wall outlet?

Topic by Boy Genius    |  last reply

What should i use for ground?? Answered

I am building the typical application circuit of a TDA2006 audio amp. I am connecting Vs+ and Vs- to the battery pack (or supply wall wart), but i dont know where or what to connect ground to. I have limited space, about 4x4x1 inches, i just need to connect things to a ground... any help is appreciated :)

Question by astroboy907    |  last reply