### Laptop Power

Hi all. I have a really old dell laptop(given to me) that is missing a power supply. It requires 20v and 3.5 amps to run. I want to make a digital picture frame out of it. I wont be using the battery or cd player and maybe not even the hard drive(not yet decided). Any idea's on what to use as a power source? I don't need to charge a battery just need power. Could I use an old pcu? I know that I could combine the two 12v lines to get 24 ish volts but won't that fry the old thing? I don't want to buy a replacement power adapter cause it is so old and may not work anyway(plus I wont lie I'm cheap lol). Any suggestions?

Posted by jmiller634 6 years ago  |  last reply 6 years ago

### 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?

Posted by randofo 10 years ago  |  last reply 10 years ago

### Power supply?

Since I was thinking of building a bipolar power supply +12V, -12V, using a 12-0-12 transformer and using only diodes and capacitors, which I have successfully built. My problem is how safe can this power supply be? since I am not using any regulators?

Asked by VAustin89 7 years ago  |  last reply 3 years ago

### Battery power

I am attempting to calculate my amp need for my garage in order to set up a 12v battery system. Using the formula; Watts / voltage = amps drawn, I have hit a question. If using a 12v battery system and converting to 110v, should I be using 12v or 110v in the formula?Example; 100 watt light bulb / 110 volts = .91 amps. Nice!But if I use the 12v; 100watt light / 12v = 8.3 amps.I'm believing I would be drawing 8.3 amps from the battery to power this light.Plus the converter draw...Please tell me which is correct?

Posted by olddawg 10 years ago  |  last reply 10 years ago

### Higher powered speakers with lower powered amp or Low powered speakers with higher power amp?

There is a lot of conflicting information on this and I would like to know if my speakers/amp would get damaged. Using 80w speakers and a 50w amp will there be any problems with running on full volume? And if I got a 100w amp with those 80w speakers will there be damage, even if I added a heat sink to the back where the voice coil is? The speakers say 80w max but not really reliable as they are well priced Chinese speakers. Speakers: 80W Audio Sensitivity: 88dB Frequency Range (Hz): 100-20Khz 4 Ohm Amp: Efficiency: 90% Rated output power: 2*50W+100W Working voltage: DC18V to DC24V The maximum output current: 4A Frequency Response: 20Hz-20KHz Can drive a 3-16 ohm speakers In the condition of rated voltage 24V The sub woofer channel at rated voltage 24V state can drive 2-16 ohm sub woofer Bass cut-off frequency independent regulation 20HZ-20KHZ adjustable Very confusing conflicting info online with under rated amps causing clipping and over powered amps frying the speakers. Originally I thought it was only bad to over power the speakers. Any help about what is worse, is appreciated.

Asked by bonze77 3 years ago  |  last reply 3 years ago

### PC Power Supply To Power CB Radio?

I have a cb radio my uncle gave me 12v 2-4 amps.. I have an old computer with a power supply with lines for 12v 6amps and 12v 8amps. is there anyway I can get this to power my cb radio without blowing the thing? EDIT I forgot to mention, this is a mobile cb radio, I'm trying to run it in the house, which is why I wan't to use a pc power supply to run it....

Posted by acer5050 9 years ago  |  last reply 5 months ago

### Substitute of Power Transistor

What is the substitute of 2N6292 power transistor? Please suggest a good substitute of 2N6292.It must be an NPN power transistor. Thank you.

Asked by SiamB1 2 years ago  |  last reply 2 years ago

### LED power supply?

I need some insight on powering 2 separate circuits. Here's what I have so far...... Circuit #1.   80 3.3v  leds consuming 400MA. Circuit #2.   20 2.0v leds consuming 60MA. Now my power supply output is 15v - 600ma, will this power supply suffice wired parallel? I do have a 9v-1a power supply too that could power circuit #2 if need be. but for simplicity of things i would like to use one power supply.

Asked by ARGMISTER 6 years ago  |  last reply 6 years ago

### PSU Power Supply

I built a PSU bench power supply, but it isnt outputing the right voltages. It just out 5v for all lines(12v,5v). It has a purple wire that is said to be the stand-by, but the psu wont start unless it is connected to the 12v or 5v line. It also says that you have to have the brown sense wire attached to the 3v wire but this seems to do nothing. How can I make this thing output the right power(12v @ 22A, 5v @ 50A)?

Posted by tylerb 10 years ago  |  last reply 10 years ago

### Power supply help?

Hi- i have an ION electronic drum kit that i got from a friend, but i somehow managed to lose the power brick. It wants 9V AC & 850mA, which for the life of me i cannot find anywhere. So, does anyone know where i can find one, or if there is something else that might work? Thanks a lot.

Posted by Samster1214 10 years ago  |  last reply 10 years ago

### led powering question

I am building a garduino since planting season is coming near and this would be a great to start me seedlings off in. right now I have 3 banks of three red leds rated at 1.8v and in one of he instructible they said 7v was sufficient but i am connecting a 9v and can only power 2 leds and also I would like to go with an ac-dc converter but everyone i found has at least 800+ mA can someone point me toward a good power supply at the end I am looking at about 25 red and 8 blue LEDs

Posted by redwind 7 years ago  |  last reply 7 years ago

### Automatic Power Switch

I am looking for someone who is McGuyver-like and able to show me how to build an outlet that allows me to plug in a power tool like say a miter saw and a shop vac. When the outlet senses a power draw from the saw, it`ll power the vacuum to start as well then when the miter is stopped so will the shop vac. I know Craftsman makes this very switch ( http://www.sears.com/shc/s/p_10153_12605_00924031000P?keyword=auto+switch ) however since it cannot be brought in to Canada, any makers out there?

Posted by Kokopelli2009 9 years ago  |  last reply 9 years ago

I already asked a question about three-phase power but my results only confirmed what I thought.  I don't understand how a MOTOR can run at 230v with three phases,  how do they rate power with these I guess.  230v outlets have three prongs, I think two are connected to the generator through power transmission lines, and one is a ground.  If this is wrong were do they get 230v because, if I am wrong all three wires connect to generator coils.  This would add up to 345v.  But to get 230v it would only be two phases.  Then it can also run on 480v, how in the world do you get to 480v.  Please help me with this.

Asked by jj.inc 7 years ago  |  last reply 3 years ago

### Power supply cooling

I'm building a power supply for my cnc machine that gives off about 37volts at 8 amps, and 12 volts at 0.9 amps. All of the transformers are from radioshack (using 6 heavy duty, 25.2volts, 2 amps transformers, 4 in parallel giving off 25.2 vdc at 8 amps, and 2 12.6 volts in parallel. Together in series gives about 37 volts at 8 amps. using 1 25.2 volts 450mA transformer, center tapped) My case does not have enough room for proper cooling such as fans. My case is water tight though, should I fill it up with something like mineral oil to keep the transformers cool?

Posted by guyfrom7up 11 years ago  |  last reply 11 years ago

### Powering Peltier Plates

Hey guys,So, I just got a Peltier plate, a device that gets very hot on one side while very cold on the other. It requires 90 watts of power. I was just curious what would happen if you powered it by USB or 9v battery. I found this tutorial which uses USB, however, I doubt it gets to its maximum coolness potential. Also, if I used a 9v, would that drain the battery in a matter of minutes, or even damage the plate?Thank you.

Posted by Joe426 10 years ago  |  last reply 2 years ago

### Multi-Source power?

Hello all, i'm thinking on a very easy way to support more than 1 power source for my electronic circuits.Below you can see the schematic. It's very basic. Each source have a rectifier diode to disallow inverse currents for each one.When both sources have the same output, both diodes will work and the output is Vin - 0.7When one of them is bigger than the other (the case on the schematic), diode on smaller source will open circuit, and the bigger is the one to be used. The output will be 7-0.7 = 6.3V.The problem i found is when there is little difference, this is less than 0.7V.This way both diodes will work but there is a difference on voltage between the two sources.Do you think that having a small resistance like 10Ohm and high dissipation in one line will solve this?Do you think this design is valid?thanks for the help in advance.

Posted by Tigrezno 10 years ago

### Xbox remote power ON

I have a softmodded original xbox, and it is located in my basement. It is a huge pain to go downstairs just to turn it on. I am looking for a solution. Originally I had planned to do WOL (wake on lan), but the nic doesn't support it. All I have to do it have something that acts like the front button: bridges two wires momentarily. Any suggestions

Posted by dwj300 10 years ago  |  last reply 9 years ago

### Tips on wind power?

I am looking for tips on creating a small windmill to charge a twelve volt battery. what is the best type of motor to use? Does anyone know how to make a charging circuit, so that even when the winds are low, it can charge the battery? What is the best type of battery? Are there any other questions i should be asking about wind power, and what are the answers to them?

Asked by cyc4015 9 years ago  |  last reply 8 years ago

### Power bypass circuit?

Hey everybody, Ok so here's the deal...I'm building some external speakers for my zune. I'm using some the board out of some old computer speakers to amplify the sound. Right now, since I'd like to make it portable, I've got it hooked up to a 12v regulator going to two 9v batteries. Since it seems to drain the batteries of charge pretty quickly, I'd really like a better way to keep them powered when I'm near a wall outlet (like when I'm at home). I managed to find an old 12v wall adapter that I could use as a constant source of power. Correct me if I'm wrong but I'm pretty sure that I can't have it and the batteries hooked up at the same time. So what I'd like to know is how do you build a bypass circuit (or whatever it's called) so that, when the wall adapter is plugged in, the board will draw power from it instead of the batteries? Sorry for the long read, and happy building everyone.

Posted by Triblade101 10 years ago  |  last reply 10 years ago

### Wireless Power Transmission

Nikola Tesla's grandest vision was the transmission of large amounts of power without wires. His work in this area was abandoned by his contemporaries, and there is still much debate over if it could or could not work. I would like to hear your opinions on this. Do you think it is possible? Would it require only one transmitter, or several, spread across the globe? Would it be safe? Would it be worthwhile? Could Tesla's original spark gap circuit been sufficient to drive it? Or would it be better to use vacuum tubes or solid state setups? Would the operating frequency be very high or very low? Pictured below is how I think Tesla may have done it, based on the information I've seen. It's a bit over-simplified, but to the best of my knowledge, it covers most of what is needed. Please note that, although the transmitter terminals would be at a much higher elevation than pictured, the receiving terminals could stay at a relatively low elevation. This link is to a YouTube video of someone using a small Solid-State Tesla Coil for wireless power transmission: www.youtube.com/watch Edit: I had orriginally imagined that the system would work by capacitive coupling between the Ionosphere and the coils. Afterwards I realized that electrostatic capacitive coupling will decouple after seperation between two plates is greater than 1/2 the wavelength (or, at least in theory), so I personally abandoned the idea. The only problem is that I can't imagine how power would be sent to airplanes. Also, this is a very good read on the subject, from a very interesting site: www.teslaradio.com/pages/wireless_102.htm

Posted by ElectricUmbrella 8 years ago  |  last reply 8 years ago

Asked by -max- 5 years ago  |  last reply 5 years ago

### Solar - Powered Batteries

Check out these cool batteries! Their creator is Knut Karlsen.See what he said:At home i always have some batteries lying around, either rechargeable or normal ones. Usually they are empty, but i'd like them to be always fully charged. I could use a normal charger and there is a lot of solar devices that charge rechargeable batteries. I wanted it simpler; why hasn't anyone made a battery with integrated solar cells? The idea of the "SunCat" batteries where born. The batteries should just bask in the sun like a cat and left for a while, in a sunny window, they would slowly recharge.For more details visit this site.Thanks!Stanislav

Posted by comodore 9 years ago  |  last reply 8 years ago

### Samsung HL67A510 no power ?

UNIT MAKES CLICKING NOISE WHEN YOU PUSH POWER BUTTON?

Asked by geeone35 9 years ago  |  last reply 9 years ago

### Power Supply and Driver? Answered

I've seen alot of the projects that have a power supply and a driver?  What's the difference between the two and why would you need both?

Asked by lford4 6 years ago  |  last reply 6 years ago

### Laptop power cord?

How do I find out which part of my power cord is bad?

Asked by jillsmith37 7 years ago  |  last reply 7 years ago

### Solar power for a laptop

Hello everyone I have an idea to build a solar power suppl for a laptop using a 12"x12" solar cell. M question is this, if I solder the leads from a power inverter to the solar cell, it should be able to power or charge a laptop correct? Is there something else I would have to do?

Posted by DaMadProfessor 11 years ago  |  last reply 11 years ago

### LED power indicator?

Just wondering how to to wire up a LED to show when a project is powered. Eg. push button switch doesn't show on/off.

### power for my robot

My robot has too many electronic parts and motors that even a 9V battery is not enough if any one has a good power source please tell me

Asked by robinsonruiz 9 years ago  |  last reply 9 years ago

### power IR LED ? Answered

How can I power 30 IR leds comes from TV remote by a 3.6volt cell phone battery. the LEDs are 1.5 volt.

Asked by asifarifin 5 years ago  |  last reply 3 years ago

### LED in parallel to power? Answered

I have a project and i am wondering if you can hook up a diode to the power source (hook it up in parallel to it) would you have to hook it to ground in some way??

Asked by astroboy907 8 years ago  |  last reply 8 years ago

### Fly Powered Planes

Flies generally buzz about and don't do much besides feed the local spiders, but here's a a couple ways to put them to work by powering tiny airplanes. Check out the models below from the 70s or the video for something more recent to show you that, yes, this crazy idea actually works. Insect Power via Neatorama

Posted by fungus amungus 9 years ago  |  last reply 6 years ago

### bb gun powerful

Hi I bought A cheap BB gun and I was wondering if it was possible to make it much more powerful that would be cool could you show me how to do it oh ya its a airsoft pistol

Posted by Monkeyfisher 11 years ago  |  last reply 8 years ago

### LED Power supply?

I have approx 200 flashing LED circut boards that I want to make a twinkling display from. Each board has a single LED that flashes about every second, each board also has a single 3v cr2032 lithium battery powering it. What Id like to do is remove the battery on each one and wire them to a DC power supply that can be plugged into 120VAC. So I actually have two questions: Should I wire these in series? Or parallel? What size power supply would I need? Heres a link to a picture of what I have. http://www.rocketproduction.com/wirefree-leds.php Thanks (in advance) for all your help!

Asked by McBeeRob 6 years ago  |  last reply 6 years ago

Hey :)Does anyone know how to power an oven resistor ? Is it really a simple resistor (I'm not sure as it is directly exposed in oven, it seems too dangerous for the user if it is simply a metal stick) ? If I plug it to 220V sine 50Hz will it heat ? Thanks :)

Asked by QuentinP16 10 months ago  |  last reply 10 months ago

### USB Power For Camera

Hello All- Big problem here and I'm way stuck. I have a Digital camera that is great however the part where I put in the batteries is bad. Ok so I have a cigg. lighter thing that has a USB slot and wen I plug my camera into it I can power it up in the truck just fine. I can also power it up from the USB on computer. Ok so I ordered a thing from Ebay that takes 4 AAA batteries and its supposed to power up USB stuff. It will not power up my camera. it just turns on then off. Then I went to home depot and they have thing thing called power to go - its also supposed to power up anything USB. Once again my camera wil lturn on then right off again. I'm not getting his at all - maybe someone can tell me why and perhaps help me find somethnig that will work as I do love this camera so much - Thanx for your time

Posted by michaeloshman 10 years ago  |  last reply 10 years ago

### Getting Power Into A Drawer???

Here's a strange question that I hope someone can answer. I've got a project which has a drawer that has line voltage going into it. My goal is to be able to remove the drawer by unplugging the line voltage. My initial thoughts were using a ribbon power cable but I can't seem to find those. Other two options are coil cord or a retractable cord. In other words, the power needs to stay with the drawer as it opens and closes. Any ideas, thoughts or experiences on how to get line voltage easily from where it plugs in in the back of the main housing and keep it connected within a drawer compartment so I can power a few outlets and other things??? Thanks in advance to the geniuses and experts out there.

Asked by pletchman 6 years ago  |  last reply 6 years ago

### pedal powered tractor

I'm no designer but here's an idea I've been stewing on for some time. I've hunted but not found any designs for a pedal powered tractor. The very early tractors were very large;could to lots of work; but they only had 2 or 3 horsepower. They ran so slow you could count the piston strokes. The designs were simple and they were work horses. Our new high horse powered gas tools often cann't do nearly as much. The old machines used heavy flywheels; slow to start but they kept on rolling. With the improvements we've made in bike gearing systems why not make a pedal powered tractor that could do serious work with that same heavy flywheel technology?

Posted by Michael Fletcher 11 years ago  |  last reply 8 years ago

### Space power plant

International project. Space station. Geostationary earth orbit. Solar energy flow. Microwave oven generator of big power. Transfer to Earth of energy in the form of a beam (microwave oven beam, microwave oven energy). Geographical point for reception of a beam - the desert. On Earth of the microwave oven energy will be transformed to electric energy. It is offered to discuss this project!

Posted by Vladimir2016 2 years ago  |  last reply 2 years ago

### magnet powered LED

Ok i remember seeing something, or maby its just a thought in the back of my head. but is there a way to make a led light up when you move a magnet by it or something like that?

Posted by yuckzee 10 years ago  |  last reply 10 years ago

Is there a fairly simple circuit, method to making a desktop power supply running on 240v a.c mains supply with a user controlled variable output say 0-24v D.C with variable ampage upto say 1 amp. I may be over simplicating thing in my head but is it just a case of a transformer taking my mains input down to the upper most requirement ( 24v @ 1amp ) on the output, and the using some type of variable resitors on the output to further restrict the output to my requirement. I would be grateful for any guidance and information on this topic. Thanks to the community in advance.

Asked by mickcaulton 9 years ago  |  last reply 9 years ago

### solar powered throwies

In case you didn't know, a throwie is an LED with a small battery and magnet attached, that can be stuck to any metal surface. would it be practical to make a throwie with a long lasting lithium battery? or a small solar cell? just a thought

Posted by Antimatter500 10 years ago  |  last reply 7 years ago

### Gasoline-powered, but no wheels...

I heard about them, but I thought they were a joke.Then I ran across a link.They actually made gasoline-powered pogo-sticks that even grandpa can ride!It's a single-cylinder engine, with the bouncing foot being connected directly to the piston, called the Hop Rod. There are a bunch of adverts and slightly more modern test-drives in a short video on the site.They're... odd.Still, I wondered. Maybe the Hop Rod provided the inspiration for other wheel-less powered transports?Do you remember those Russian boots? 4 metre strides and speeds of 40kph were promised, but that was 8 years ago. According to The New York Times they fell foul of Soviet secrecy and then Russian financial mis-management.They're still around, waiting for some entrepreneur to hop on the band-wagon...

Posted by Kiteman 10 years ago  |  last reply 10 years ago

### How to power an electromagnet? Answered

Is it better run an electromagnet of a bigger voltage(12V) with a smaller current(150mA) or with a smaller voltage 5V and a bigger current? Which will heat it up less? Does it even matter? The electromagnet will have to work for several hours so heat is my main problem. Also should I use thicker or thiner wire? I'm trying to build a electromagnet for a ferrofluid project.

Asked by odvratno.zgodan 7 years ago  |  last reply 5 years ago

### Campfire powered foundry?

Hey guys, Ive been checking out a few of the foundry instructables here, and I want to make one. I have 2 problems. 1, I don't have any charcoal, and two, I don't have a fan. So I was wondering... is there a way that I could make a foundry that would get the heat from a campfire or firepot? I'd there are 101 uses I can think of for molten aluminum.., Thanks in advance! IaC

I'm looking for some help in constructing a portable mechanism to attach to a manual wheelchair and to the front of a bicycle while still using the wheelchair handles to manouvre the wheelchair.  The front wheel would have to be removed in order to utilize the wheel chair handles to steer.  This attachment would be for two elderly people able to get out but not able to walk far.  Using this converted mode of transportation would make life so much easier.  The wheel chair is presently folded in the trunk of a car and the bike could be attached onto a bick rack for sightseeing purposes.  Any ideas out there?? Thank you,

Asked by huot 8 years ago  |  last reply 3 years ago

### solar powered cooler

Using these ideas as a starting point:http://en.wikipedia.org/wiki/Icy_Ballhttp://en.wikipedia.org/wiki/Einstein_refrigeratorhttp://en.wikipedia.org/wiki/Gas-absorption_refrigerator"Another variant uses air, water, and a salt solution. Warm air is passed through a sprayed solution of salt water. The spray absorbs humidity from the air. The air is then passed through an evaporative cooler. Humidity is removed from the cooled air with another spray of salt solution. The salt solution is regenerated by heating it under low pressure, causing water to evaporate. The water evaporated from the salt solution is recondensed, and rerouted back to the evaporative cooler."Directions on how to make an icy ball. URL works occasionally.http://crosleyautoclub.com/IcyBall/HomeBuilt/HallPlans/IB_Directions.htmlhttp://blog.modernmechanix.com/2007/07/19/refrigerator-uses-solar-energy/Is a non-flammable, non-toxic, and low pressure version possible?

Posted by beforethought 10 years ago  |  last reply 2 years ago

### Powering Video Game Consoles with Single Power Supply?

I'm in the planning stages for a office/video game room. I own a lot of game consoles — around 20. I want to hook them up to two televisions — one HD plasma and one SD CRT (older ones will probably go to the CRT). I'm starting from an unfinished basement, so I have a lot of freedom for the design. One thing I really want to avoid is a rat's nest of cables — 20 consoles can result in a big mess. I'd also like to avoid having wall warts draw power when I'm not using their respective console. With that in mind, plus a desire to introduce a little automation, I'm planning to use an arduino (probably a mega 2560) along with a bunch of relays and a power supply of some sort to do this. For consoles with internal power supplies, I'll run AC through some relays. But for the DC ones, is there anything I should be worried about? I plan to use voltage regulators (possibly variable along with some digital pots) to set the correct voltage for each console. Should I put fuses in line? Diodes? I should mention that I don't plan to ever have more than one console on at a time. That said, I do plan to use a desktop PSU or something like similar that can provide plenty of amps. I don't yet know as much as I'd like to know about DC and what constitutes a good source of power, and I just want to make sure I don't fry any of my consoles through some rookie mistake. I'd appreciate any advice, suggestions, etc. Thanks!

Asked by fwonkas 3 years ago  |  last reply 3 years ago

### High power LED flashlight power supply questions Answered

I'm currently in the process of building a high power LED flashlight from scratch. I've decided to go for AA batteries as a source of power, however, I am not sure as to whether 2 AAs will be enough to drive my LEDs. The LEDs are from a 5W LED bulb putting out ~360lm. I'm assuming the bulb itself has 5 1W LEDs connected in some sort of configuration, but I'm going to run them in parallel. I'm planning on running it on either Alkaline or NiMH. However, I'm not quite sure if there will be some sort of voltage drop with the load I'm going to place on the system (~1A @ 200mA each). Also, 2 NiMH will only have a combined voltage of 2.4v making me a bit skeptical as to whether it would even run. I already have a design for the flashlight for 2 AA batteries. Adding a third battery would complicate the design though, maybe requiring me to make a battery pack or something. So, will a 5x1W LED array in parallel run from a 2.4v NiMH power supply? Or do I have to go with 3 batteries plus a current limiting resistor?

Asked by beehard44 5 years ago  |  last reply 5 years ago

### Power supply does not supply power. zoom g2.1u Answered

Either that or the zoom pedal isn't working. that's my bet, it's the stock power supply . it runs fine on batteries, albeit for a short time.

Asked by Icarus1990xx 9 years ago  |  last reply 8 years ago

### Wiring high-power LEDs with a switch and power source?

I'm looking to wire 5 high-powered LEDs to both an on/off switch, as well as a five-way selector switch, to change between LEDs. From doing a little research, I'm guessing that you would wire the switches between the circuits and the power source, but I'm not exactly sure how to do this. I'll be using Luxeon LEDs, along with simple driver circuits I found on here. I'm still confused as to how to power it, and how to wire the switches. Any help?

Asked by supermario2100 7 years ago  |  last reply 7 years ago