Search for power source in Topics


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.

Topic by Tigrezno  


Small power source

I was planning to make LED jewelery, but would need a very small power source. In the best case it could be powered by the body's movement. Is there anything small enough to bit on a wrist, yet can power about 10 LEDs?

Topic by DemonDomen    |  last reply


NiChrome Power Source? Answered

So, I'm doing a project that needs to boil maybe 8-10 drops of water very quickly. I was thinking of using NiChrome wire to do this as in the included diagram (sorry low quality, MS Paint). However, I can't seem to find an appropriate power source. So, I need some easy to obtain powersource that is also relatively small. Something like batteries, a capacitor bank, or anything similar. Remember, it has to be able to boil of those 8 drops pretty fast, lest they condense in another part of the pipe before the desired pressure is reached. 

Question by LiquidLightning    |  last reply


Converting Power Source

I am trying to convert an electric string of LED lights to 12 V battery power. (I am using them on my golf cart, which has a 12 V battery and would like to run the lights using a switch that is attached to the battery.). How do I do this? I have attached a photo of what I have.

Question by RobinL91    |  last reply


Power source for coilgun? Answered

I have built 2 coilguns already using a camera circuit for charging the capacitor bank, but because it is a disposable camera, the quality of the circuit wasnt very good so it stopped working like in a week or so,, so i was wondering if i could build a circuit for charging a capacitor bank (so i wont need to buy any more cameras), but i've already looked in a lot of pages for a schematic but i've got no luck anyone knows how to build a circuit for this purpose? i do not have a lot of experience in building circuits, thats why i dont figure it out myself thnks

Question by tato312    |  last reply


I am using 4 servo motors operating on same arduino board.Power source I am using was 12V 2A adapter.Is it sufficient?

Since a servo motor operating voltage is about 6v.Is it safe for motor to use 12V 2A adapter?Power for all 4 servo motors are is supplied from ardunio board.All 4 servo motors are connected in parallel. 

Question by ganesh27    |  last reply


How to build a battery charger for a 3.6v 60mah battery?

Hello guys, I have this idea I want to make a "power source" using this battery(pic) I want to use 3 to 4 batteries in series to power up some of my ideas. can someone tell me hat I need in order to make this happened? I will really appreciate the help thanks...

Question by dreven85    |  last reply


Can 2 different dc power supplies be added together at the same time for a larger amount? Answered

Hi, I am wanting to provide 96 volts of DC power for a project,  however it cost so much money to buy a power source that big.. can I add other DC power sources to add up to what I want?   or is there an inexpensive way to get it with out all the hassle? Bryan  

Question by bboyden    |  last reply



Coil + magnet = power source

People, I need your help! I'm a student at college and my primer subject is physics. Let's just say I know enough about electricity and power. But my major obstacle towards constructing stuff is electronics. I have only just scratched the surface of it. I want to make a power source out of a coil and a magnet inside (electrical induction). Can anyone point out how exactly to build the thing? My desired output voltage is about 5V, or sth. I'll use it for electronics, so the amperage doesn't really matter. I would also like to see a circuit that converts AC to DC, cause the coil will give out only AC and that's not good. Thanks in advance!

Topic by 5ar    |  last reply


Coil + magnet = power source.

People, I need your help! I'm a student at college and my primer subject is physics. Let's just say I know enough about electricity and power. But my major obstacle towards constructing stuff is electronics. I have only just scratched the surface of it. I want to make a power source out of a coil and a magnet inside (electrical induction). Can anyone point out how exactly to build the thing? My desired output voltage is about 5V, or sth. I'll use it for electronics, so the amperage doesn't really matter. I would also like to see a circuit that converts AC to DC, cause the coil will give out only AC and that's not good. Thanks in advance!

Topic by 5ar  


LED's with separate power source? Answered

Can I have a circuit which runs from a power supply, this circuit has LED's in it, could I make it so that the LED's are still in this circuit but, they run from a separate power supply to the rest of the circuit? If so, how?

Question by henryplumb    |  last reply


Motor + arduino power source? Answered

I am adding a 12v DC motor into an arduino circuit. The motor will be switched on and off controlled by a transistor controlled by arduino. Should the arduino be powered by the same ~10v power source, or should the motor power source and arduino power source be separate (but have a common ground). (The reason I am using ~10v is because I have 8 NiMH AA batteries as my power source for the motor and it runs just fine at that voltage.)

Question by sblaptopman    |  last reply


A small AC power source? Answered

I want something to power LEDs from (I want to stop fussing about the polarity), preferably cheap and compact (I've no intention of buying a lab power source to play with it once in a fortnight, and I don't have the money). I thought about mobile phone chargers, laptop chargers and model railway power sources (I own one of these), but they are all DC. Can you think of something? PS Is it true that a motor connected to an AC source would stay still?

Question by gruffalo child    |  last reply


2 Voltage Regulators, 1 Power Source?

Is it possible to use two voltage regulators of different values with one power source?

Topic by flagrantfouler  


Alternative power sources for a coilgun?

I was wondering if there was any other method to power the firing coil of a single stage coilgun without using capacitors.  My main reasoning is to try to reduce recharge time, and to also avoid making massive groups of capacitors and finding a place to put them. It needs to be able to be powered by some form of battery, meaning I could connect voltage to this circuit (1.2 volts up to 12 volts.  I'm not picky) and shouldn't consist of hard to find components. I'm not looking for the greatest efficiency in the world, just making a step (okay, maybe a stomp) toward building a 'capless coilgun'.

Question by Madrias357    |  last reply


AC power source for a blinking LED ?

AC power for a blinking LED ?.............how 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


350 Projector bulb power source?

Hey guys I recently salvaged the bulb from and InFocus LP1000B projector. I want to use this bulb as a light source but am not sure how to go about this because I do not know the voltage to run the bulb at or if the power to it needs to be limited somehow. From my research I believe it is a 350 watt Metal Halide bulb. Thanks for any help.

Question by nurdee1    |  last reply


Multiple drills sharing a single power source

Would it be possible to run multiple cordless drills off the same power source? I do not want to run the drills all at once, but rather have them share the power source. I was thinking of modifying an ac adapter with a voltage and amperage less than the tolerances of the drill. Are there any safety concerns? If I do this will I blow myself up? Could I run them at a higher voltage/amperage? Is this idea dangerous and stupid or just stupid?

Topic by ehudwill    |  last reply


How do I convert an AC power source to a DC power source?

I have a small motor and a wall adapter for an answering machine. I need the wall adapter to work with the dc motor... any idea? A capacitor, maybe?whenever I hook the wall adapter to the motor, it does a very predictable thing (vibrates uncontrollably..)EDIT: I figured it out, with the help of the answers belowhere is what i did...

Question by nepheron    |  last reply


I'm building a stand-alone speaker from a pair of car speakers. Do I need an extra power source? Answered

I bought a pair of car speakers from a thrift store because they were different than any I've ever seen. Where the dome should be, there was a tweeter sticking out. I already have a box I would like to put them in, but I need to know if they will be driven by the sound or if an extra power sources needs to be connected. I would like to have an option to use wires like a normal speaker or through an aux. There will be two in a box and I want to connect them. I would also like them to both use the same power source if needed. http://www.caraudiogiants.com/infinity-kappa-62-9i.html?___store=default&___store=default That is the model, but one of the ends is cut off of one, and the other is nearly unusable anyways. Other than that, they are perfectly fine.

Question by metalshiflet    |  last reply


Id like to build a small test tube heater with nichrome wire. Where do I start?

I would like it to be variable from ~100C-400C and have minor experience in electronics.

Question by GalaxyX    |  last reply


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?

Question by supermario2100    |  last reply


I want to change my speakers which have an ac input into a dc input so I can have them portable Any help ????

Basically I really need help here. I just bought a set of old small speakers and I wanted to turn the Ac input into a Dc input and I have no idea how to any ideas ?? The step down transformer is inside one of the speakers and I'm not sure how to make it into Dc Money's not really an option but I don't really want to buy more speakers most appreciated Ed :D

Question by 3dwardify  


How to power multiple servos with an external power source?

I need to power the following servos (with the following quantities): 1 x HS-422 Servo Motor, 2 x HS-645MG Servo Motor, 1 x HS-755HB Giant Scale Servo Motor, 1 x HS-805BB Giant Scale Servo Motor, 1 x HS-485HB Servo Motor. I have an arduino uno controlling them but am powering them off of 1 6v 2800mAh NiMH battery (I have 2 at my disposal though). I am using the power strip on the side of my breadboard. I connected all my servos and battery to the same power strip. My servos seem to be going crazy when I have more than 1 connected (they don't listen to the input and just keep going from 1-180 degrees). I have attached the layout below.

Question by Science102    |  last reply


Connecting two DC power sources

Hi all,I'm working on a project where I will have two DC generators that are being powered by spinning turbines. These turbines will be spinning at different speeds and these speeds may vary over time (i.e. the voltage from the DC sources will almost always be different). There will also be instances where one isn't producing any voltage at all.I was wondering what it the best way to connect them? Should they be in series or in parallel? Should there be diodes?After they are connected the DC power will be fed into an inverter and converted to AC power.Thanks for any help!

Question by KiannaB3    |  last reply


¿What power source is more efficient?

For a project I have to decide between a mechanical generator (I.E. one attached to a bike's wheel) o an array of cheap solar panels.Anyone has experience with this? What is your advice?I only need to supply power to recharge four generic AA batteries once a day.Thanks!

Question by Daniel FranciscoD1    |  last reply


Multiple Circuits to one power source

I am working on finalizing a circuit bent sculpture I've done for my undergrad thesis. I have three circuit bent items, each with it's own battery source within the sculpture. Here is my dilemma: normally I plug in the batteries when I show it to someone, then promptly take them out, but for my gallery show, the sculpture will be turned on for an extended period of time each day, in my absence. What I would like to do is connect all circuits to one battery source or AC power. After that I can add a switch so that the gallery attendant can turn in on/off as needed. I am looking for any tips on how to do this. As of now, one runs on a 4-AA pack, one on a 2-AA pack, and the last on a 9-volt. Adding these together I am getting 18V(?) and I have an old laptop adaptor that has an output of 18.5 volts. I have a video of the piece functioning if anyone is interested. Thanks for your help (in advance).

Topic by idaholaura    |  last reply


Stungun for power source for coil gun?

I’ve made a coil gun out of a disposable camera (utilizing it’s capacitor). It shot bbs about 3 inches, and then they’d roll along the floor. To get coil guns to work you need a high voltage, discharged quickly. I’ve seen there are cheap stunguns on Ebay you can buy for $12-$15 shipped. In the 2.8 million volts range. I think they have enough voltage to propel a bb pretty good, but my question is do they discharge fast enough?  

Topic by G.A.Pster    |  last reply


Using body heat as a power source

You've heard of geo-thermal energy, but what about homeo-thermal energy? I know I sure haven't, mostly because I just made up that word :) Bad portmanteaus aside, what do you guys think of this concept? Running or charging things using the body heat you generate throughout the day and especially during the night. I'm not sure how plausible it actually is, or how efficient it is, but I thought it'd be a nice project to start working on and wanted to know what you guys think of it. Is it worth-while? Too complicated? Not scientific enough? I'm interested in your feedback! :)

Topic by kenizl86    |  last reply


Any Power Source USB Charger

So here what I have in the works, I'm trying to make a pocket sized gadget that will charge a USB device from anything,  Normal 110v AC, And anything from 4 AA Batteries to a 28v Cordless tool battery,  to a Car Battery, Solar Panel in the middle of Mars, etc, Anything giving off Between 6-35V (Be nice if I could find a 7805 that had a Vin (Max) of 40V, Several manufacturers make 36v cordless tools) . I'll use alligator clips to attach to the battery of choice, and I'll throw in a Diode bridge to make it idiot proof. I plan on having a switch between an AC and DC Circuit. And of course, I'll throw a decent sized heat sink on the regulator. Any Suggestions? I'm not the most electrical savy person out there, so if you foresee any problems, let me know.

Topic by misterpicture  


Alternative knex gun power source

I think this situation has happend to everyone once(pulls pin back)*SNAP!* "dang it, my rubber band broke"and let me say i HATE it when that happens, i got so tired of it that i decided to try an alternative, what did i use? Springs! I bought a pack of springs for $3 and lets say they work perfectly! they made my new sniper rifle fire over 80 feet before it hit the wall, so i dont know the exact range and i though i was set for a month of 2! ...well untill the 3rd day of useing them... the one i was useing got alot weaker i started to realise before i could hit the target on the wall without aiming upwards, now it dose not even reach 60 feet! (i noticed after i did my video) my first reaction was to check the breach load for any fragments of broken cartrages. none to be found. i thought "oh maybe the pin's tape has to be replaced (easy enough) as i took the main gun peice (the part of real barrel and breach load stuff not like handel or stock) it hit me! when i first used the gun my shoulder would pop and i could not get that strong in 3 days. and as i stared at the pin it seemed the spring had stretched! (this is a expantion spring so thats not good) now i am very upset cause i am on the 2nd spring and it took me forever! to get the pin exactly right the first time.so thats why this is here for any good ideas on how to have strong (yet long lasting) power sorces cause lets say RBs dont seem to like me and springs can get anoying and expencive.

Topic by Sypran    |  last reply


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?

Topic by jmiller634    |  last reply


iron man suit ideas

Hey Guys I am thinking About to build à suite likje THE picture  but i am thinking à lot of people is making à suite like ironman but is made of foam but do you want to make it from any kind of metal i do. i am thinking à lot of à Helmet first with à screen inside.... we must thinking of cooperate share picture or something Lets start with THE real stuff  Greetings from Holland  Marijn 

Topic by mvan h1    |  last reply


iPod Power ... BUT!

Here's the challenge:I have a Belkin SportCommand iPod Remote and it works great. However, it uses the iPod's connector port and draws its power from the the player. I have this thing installed on a waterproof boombox that needs to play tunes for 8-10 hours at a given time and I don't want to have to open the box AT ALL (lots of water + electronics ...).So, I need a way to have both the iPod accessory plugged in and, at the same time, charge the iPod from a 12v power source (like most car stereo iPod adapters do. I think this is as easy as a little plug to go inbetween the iPod and the accessory, but I can't figure out which pins to tap into. There are a lot of different power pins on the connector, and I need to know which two (ground and V+) are the *charging* inputs.Ideas/suggestions/comments? Thank you!

Topic by tridens  


Wireless Power?

OK so recently I have noticed that almost any sort of power can be converted into a different type, sorta. Anyways, it takes power to create radio waves or any wireless wave. Would it be possible to just send out plain radio waves and get something to pick them up and convert them into usable power? Now I know the farther you were from the source, the weaker the power would get, so you might have too send out a fair voltage signal to get some good range. Also, would it interrupt any electronics in range or anything like that? I was just thinking about this and wondering if it is even possible to get actual wireless power around your house or something without using batteries or interrupting anything in your house. Thanks.

Question by noobererer    |  last reply


Wireless Power

----- Click Here for Full Story -----We may be able to say goodbye to power cords in five years, as Intel has developed a system called WREL (wireless resonant energy link) that could possibly run electronics without having to find a wall socket."Wouldn't it be fantastic if we didn't think about where the power was coming from and the power was everywhere?"said by Intel boss Justin Rattner in an interview with BBC. Rattner explained that through Intel's idea of "magnetic induction", the power source can be tuned through a resonator, enabling gadgets to receive power wirelessly. The report further explains:"Power is put into magnetic fields at a transmitting resonator - basically an antenna. The receiving resonator is tuned to efficiently absorb energy from the magnetic field, whereas nearby objects do not."Of course, there would be issues at hand if Intel's technology breaks through the mainstream. How are companies such as Monster Cable going to fair if this new possibility rises? Well, we'll just have to see until then.Just how long till someone makes this cheap?

Topic by Keith-Kid    |  last reply


I need a 7v 1.2A DC power source

I have a Brother label maker that i requires 6 1.5v AAA batteries. I don't want to fill it full of batteries but instead use a DC power supply. It requires 7V 1.2A DC, and I'm not sure how to get this. I have a variable power DC supply and some wallwarts but none of them fit the specs. I tried hooking up 7V from my power supply but no dice. How do i make sure it gets 1.2A? Anyone have some knowledge they'd like to pass on? Thanks

Topic by Korey    |  last reply


Need to build a 12 volt 3.2 amp dc power source. Help?

I picked up a nice flat panel monitor, cheap, but seller wouldn't part with the brick he had.(needed it for her monitor) I have pc power supplies and can scrounge with the best for other bits required. Would someone please help. Thanks

Question by hezandry    |  last reply


Need help sourcing a battery for my project?

I'm in the development stage for my next couple of projects, and after thinking about variables and other such random stuff, I've decided on a project (no, I won't tell you what it is. not yet at least!). The project is going to have to be very small, and will really be stretching the limits of through hole soldering (I dont want to to SMD on this). Due to size constraints, and power consumption, I need a very specific size battery. I need a battery with (I hope) at least 700mah capacity, if not more, as well as be rechargeable. Diameter should not exceed that of an AAA battery (around 12mm or so). Voltage CANNOT be 1.5, and must be more than 2v (single batteries only please! Multiple cell batteries are fine, as long as they are in a single package). Length of the battery can be pretty long, but should not exceed more than 40mm or so. Battery can be any rechargeable type, with the exception of Li-ion flat packs (I think they are a bit too fragile and volatile for a project exposed to daily wear and tear.). My current choice is a 123A li-ion 880mah battery, but it is a bit too wide for me.. Anyone know of a good, rechargeable, small battery? I know this is really stretching my choice limits, but I would GREATLY appreciate any help you give. Many, many thanks in advance,  -Thomas

Question by astroboy907    |  last reply


Alternative power source for power-tool enhancement design project? Answered

Hi this is my first post here :-) I'm a Design student in London currently researching power-tools. I've made this really crude prototype of a system that looks at enhancing the vibration of a power-drill by vibrating the user as they pull the trigger on the power-drill. It consists of a 12v 55AH car battery running through a 300watt 12v to 230v inverter which in turn powers a cheap 135watt 230volt orbital sander. It's all mounted to a British Army paratrooper clansman radio pack frame and has a very crude wooden arm with a temp on/off toggle switch mounted inside a vitamin c bottle :-) and tapped with gaffa tape, very much bricolage.... I used what I had to hand and what was cheap, i know it's not safe (yet) but i'd like some opinions on alternative smaller and lighter power sources? I know I could just use cordless sanders but there expensive and i need multiple units 2-3 and as this is only a small part of what I'm doing so cost is an issue. I'm considering looking at cheap 12v battery packs from cordless drills but don't fancy using lithium and blowing myself up? All suggestions and opinions appreciated! Thanks James

Question by le_bricoleur    |  last reply


Alternative power source for power-tool enhancement design project?

Hi this is my first post here :-) I'm a Design student in London currently researching power-tools. I've made this really crude prototype of a system that looks at enhancing the vibration of a power-drill by vibrating the user as they pull the trigger on the power-drill. It consists of a 12v 55AH car battery running through a 300watt 12v to 230v inverter which in turn powers a cheap 135watt 230volt orbital sander. It's all mounted to a British Army paratrooper clansman radio pack frame and has a very crude wooden arm with a temp on/off toggle switch mounted inside a vitamin c bottle :-) and tapped with gaffa tape, very much bricolage.... I used what I had to hand and what was cheap, i know it's not safe (yet) but i'd like some opinions on alternative smaller and lighter power sources? I know I could just use cordless sanders but there expensive and i need multiple units 2-3 and as this is only a small part of what I'm doing so cost is an issue. I'm considering looking at cheap 12v battery packs from cordless drills but don't fancy using lithium and blowing myself up? All suggestions and opinions appreciated! Thanks James

Question by le_bricoleur    |  last reply


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

Question by robinsonruiz    |  last reply


How to make a voltage multiplier?

I need to make a voltage multiplier that is cheap and easy to make and can get up to 20 times the input voltage(12 volts).  Its for an electric car design.  Can anyone help?

Question by Kalrag    |  last reply


Help needed to install small remote listening device in to a child's battery operated toy

Hi I'm new to this site, I need help in installing a small remote listening device (simcard type) into my child's toy, I already have the device and the toy which I'm going to use, the toy is battery operated, I just want to know how I would connect both items so listening device receives power from toy batteries. Listening device dose have its own power supply but it runs out of power after a few hours. can any one help

Topic by Alik112    |  last reply


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??

Question by astroboy907    |  last reply


What would it take to make a power loop, that couldn't necessarily power anything, but could loop? Answered

 Like if you had a power source connected to 2 wire's and then you connected those 2 wires to a switch and then back to the original wire's. And then you'd switch the power from the original power source, to itself. What would it take to make a power loop that wouldn't power anything essentially, but would still run in a loop?

Question by gabe94    |  last reply


High Output portable power source, possibilities?

I'm designing a large scale robot, and I want a generator of sorts that runs very efficiently for a sustained period of time. It would need to be able to power 13 Large electric motors, 29 smaller electric motors, and run a smorgasbord of electronic systems to control them. Ideas? It needs to portable, long lasting, and be able to take on the demand of everything.                

Question by Slashaar    |  last reply


Semiconductor based switching with a different power source?

Lets say I want to switch on a circuit, that runs on one power source, with a different power source. I know this can be done easily with relays with the coil attached to one power source and the remaining pins to another power source. However, I want to know if something like this possible with electronic semiconductor based switches too. I am trying to make a USB based power outage detector for my computer that can help me in safely shutting down my computer automatically when I am not there to manually shut it down. A male-female USB extension cable of a very short length can be stripped and the red wire (+ve) can be split and connected to an electronically controlled switch which will remain closed as long as it receives current from an external power source say a wall adapter. As soon as the power fails, the switch is opened. A simple USB device like a flash-drive can then be connected to the female end of the cable and the male end of the cable to the computer. A simple C program will check at specific time intervals if the flash drive is accessible. As long as there is power, the program will be able to access the flash drive. As soon as there is a power failure, the program will no longer be able to access the flash drive and start the shut down process. Do have any suggestions?

Question by raftor    |  last reply