### Power supply

Last time I tried to do my own homemade project I failed utterly, I think mostly because I had no idea what anything was (if you saw my last topic on a distortion petal, you know what I'm talking about). I decided instead to buy a book (Tab Electronics Guide to Understanding Electricity and Electronics by G. Randy Slone) which has projects in it, the first one being a power supply. I haven't started building it yet (waiting until I get back to the city) but I've started looking up parts. The thing is, I can't find a 4400-uF 50-WVdc capacitor anywhere! So my question is, can I just put two 2200-uF 50-WVdc capacitors in parallel to do the job of one of the 4400's? That isn't my only question, just the first which I'll ask later in this thread. Thank you (PS: Has anyone had a problem with using Chrome and entering text into these fields? I had to switch to Firefox to get it to work)

Topic by gohuskies   |  last reply

### 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?

Question by VAustin89   |  last reply

### Power Supply

With this circuit, does it matter how many amps the input is rated at? The output is supposed to be 2 amps at 9 volts

Topic by TheLostAmish   |  last reply

I need to make a 6.5 vdc - 500ma power supply I have no clue how to make it 6.5v. any help is deeply appreciated

Question by BluTiger   |  last reply

### 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.

Question by ARGMISTER   |  last reply

### 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.

Topic by Samster1214   |  last reply

### OEM Power Supply

I have an unregulated power supply, with a bridge rectifier. I suspect that the rectifier is damaged. I measured the components and the voltage on the rectifier, every connection past that measures 0 volts. Shall I replace the 4 diodes?

Topic by knektek   |  last reply

HEY! I recently took out a 6V DC motor from a CD player. The problem is that I wanted it to power through the mains but have a 12V step  down transformer. So, my question is that whether there is any way  I can  power it?  (except by using a 6v step down transformer) Thank You

Question by pranjal12   |  last reply

### power supply cooling

Normally I'm pretty good with electronics, but I need some help with this problem. I'm building a power supply for a cnc machine and I need help designing a circuit to power fans when it's over a certain temperature. Here's some things it needs: 1) 12 volts supply (easy with a transformer and filtering it) 2) power fans when it reaches a certain temperature. 3) still keeps the fans on even though the rest of the system is off. 4) after the system if off and it's down to temperature then the transformer turns off, to save electricity and to not make it hot after a long time. If possible can someone draw up a schematic? Thanks in advance!

Topic by guyfrom7up   |  last reply

### Computer Power Supply?

Can i use a 20+4 pin power supply on a 24 pin motherboard? THANKZ!!!!

Question by sci4me   |  last reply

Hi Guys! I need some help. I recently got several pc power supplies and I don't know how to turn them on. That sounds stupid, but I don't really work with them much. I tried plugging it in expecting the fan to at least turn on, but nothing happened. No outputs from any of the leads either. What am I doing wrong? Thanks!

Question by transistorguy   |  last reply

### 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?

Topic by guyfrom7up   |  last reply

### power supply to arduino

Actually i am trying to make a web connected robot after seing it from instruct table.com the wiring skeem which is shown in it is :- they are powering the arduino with a 9 volt battery from the connector and running the servos with the 4AA batteries so i also done the same thing but when i done it then an error starts comming while uploading the programe on the board so i contact the manufacturer of the board so he told me that your chip has got fried and if you further want to protect your chip so set the jumper before providing external power supply but on instruct table they directly have done all the wirings they does not have told of jumper and all. as i am really new to arduino i does not know how should i set the jumper.so please help me out..........

Topic by armaghan rehman   |  last reply

### power supply help

Hey I need help building a pedal brick power supply like the one here. i could just buy one but it wouldent be as fun, and i would rather build one if any one can help or knows of a schematic with multiple 9 volt outs i would appreciate your help.

Topic by chrischavez   |  last reply

### rca power supply

I was wondering if anyone could post how to make a simple rca power supply for a tattoo machine. Just a plain rca female input like off the game cords, not the guitar amp. it needs only to supply 3-4 volts of power. maybe an old walkman or something? when i have the smallest cutest girly homeade tattoo machine that i want to post but i want to make sure it works properly first, it runs off batteries right now but i want to be able to plug it in. if someone does this project could they msg me when its posted? thanks :)

Topic by Mendalite   |  last reply

### Making a power supply.

Hi. I have an amplifier. It needs a 12v-0-12v transformer. I have two 12v adapters. Can i attach these two adapters like this(shown in image) to get 12v-0-12v???

Topic by Shezi007   |  last reply

### 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)?

Topic by tylerb   |  last reply

Question by -max-   |  last reply

### simple power supply

I have a project that needs a 24VDC input, at only about 300 mA. I don't have any 24V power supplies, wall warts or anything else lying around, but what I do have is a 120 in, 24 out transformer, a bridge rectifier, and a large cap. Is there any reason why I shouldn't just use those? I'll put a fuse on it. I have some 317 voltage regulators but they dissipate too much to provide the full 24V. 317s are short-protected and the like, which obviously my little kludge wouldn't be, but beyond that, is it a bad idea? thanks,

### Electronics for power supplies

First, I apologize for being (almost) the hardware version of a "script-kiddie". I do want to learn the techniques involved but all of the electronics courses I've found work the wrong way around. They teach "this is what we have and this is what you can do with it" whereas my brain works in the "This is the problem, here is a solution and this is why it works." manner. This is how I learned software but when you get it wrong you can start again without losing the magic smoke! I have a 250ah, 12V battery bank, multiple DC devices requiring power and, eventually, several power sources for recharging. I also have several MC34063 chips and a few higher amp chips (somewhat optimistically as it turns out). Firstly, is there a practical course online that is built around this? Secondly (and probably extremely basic), if a device draws, for example, 3A is it self-limiting or do I need to put something between the source and the device too restrict the power?

Topic by ImmortalSoFar   |  last reply

### power supply for amp? Answered

Hello!! i built a LM386 amp recently, and i am attempting to build a power supply for it...which is a challenge. so do i have to use a regulator or what? im new to voltage from the wall, i usually build them with batteries, so im new to it. do you think you could post a setup for amps like that that? thank you for your time))

Question by ski4jesus   |  last reply

### 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?

Question by lford4   |  last reply

### Flash Power Supplies

I don't have a lot of money to spend on stuff at the moment. What I do have is flash guns. Four of them in fact, three of which can be fired with triggers. Now I could invest in 16 rechargeable batteries. Or should that be 32 in case I run out? And a crap load of chargers.  And extensions cos we have no spare sockets in our house. But that just doesn't seem right to me.   Heres what I propose : 1) make some dummy batteries from wood with wire running through the middle.   Three of these go in each flash to carry the connections  2) a fourth dummy battery carries wires out of a small notch in the battery flap door 3) said wires are connected in parallel to a large rechargeable battery - I reckon a 6v from an old British motorcycle (fast draining) or from a granny wagon (deep cycle) should do the trick.  4) when I'm done shooting I charge this single battery from the mains charger I have (does 6/12v) I figure 4xAA batteries at 1.5v = a 6v battery, bu extra size should last longer, be more convenient than carrying around dozens of AAs and changing them and if I want to use AAs when our and about I still can   Any reasons tho wouldn't work or I shouldn't do it?

Topic by ohowson   |  last reply

### Power Supply and LEDs

Just wondering what i could do with my old computer power supply? THANKS.... Also...What bout LEDs ....what can i make with them??? THANKS

I 'accidentally' loaded the atx power supply with 10 amps. It is requires 4 amps to work, I am worried that the protection circuits will be blown. Would it be safe to use now with a 4 amp supply now? I live in the U.K.

Question by knektek   |  last reply

### power supply for LED's? Answered

I have a strip of LED's that have a warning that's says use only with a 12v class 2 power supply. Is this referring to an AC/DC transformer? Should I be able to run them straight from a 12v battery? If I am using a 12v battery is the class 2 circuitry still needed?

Question by MDheliMech   |  last reply

### Gateway Power Supplies?

I have a Gateway 24" LCD monitor, model # LP2407, with a bad power supply. Does anyone know where I can purchase parts for Gateway products? Or does anyone know the company that produces the monitors for Gateway? Gateway is useless, they directed me to companies that are resellers or Gateway's computers. I've checked with several local repair shops, all said, "Good luck, buy a new monitor."

### 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!

Question by McBeeRob   |  last reply

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.

Question by mickcaulton   |  last reply

### Are these power supplies good?

The cheap bare metal power supplies from ebay or other sides have been reviewed many times on youtube and people have found that they are actually decent. But I cannot find any reviews of the sealed plastic kind of power supplies. The "bare metal" ones I am talking about look like this, and the "sealed plastic" ones look like this and this. Edit: None of your replies answer my question. I am not asking which one I should choose, I am asking if the plastic ones are just as decent as the metal ones. There are a few reviews of the metal ones, and people have found that they are actually quite decent. Here are some: https://www.youtube.com/watch?v=vwFrP7uK5lM https://www.youtube.com/watch?v=71NWT5vrbk8 But I cannot find any reviews of the plastic ones, so I don't know if they are just as good. I am asking if anyone has gotten any of these and made a review with some tests, or knows of a review of these.

Question by poiihy   |  last reply

### Led Power Supply?

I am going mad over trying to figure out what power supply I need. I am making an arduino controlled aquarium fixture and plan on using 30x3w leds. From what I understand using resistors could cause fire and I don't want that of course. I like the look of laptop drivers like this one http://www.gapsupply.com/LED-Power-Supply-p/12v-dc-nwp-96w.htm but I cant figure out which one I need. I have seen all the instructables for this and everyone seems to tape 8 meanwell drivers together. I dont want a big bulky ugly mess like that just one power supply to do the job. The smaller and more compact the better. I will be running 2 rows of white on the outside and one row of red in the middle. 10x3w leds per row. each row individually dimmable via ir and tft. here is the led specs. Whites: http://www.ebay.com/itm/390908787444?_trksid=p2059210.m2749.l2649&ssPageName;=STRK%3AMEBIDX%3AIT Forward Voltage: 3.2-3.8V-700MA Luminous flux: 200-230LM Output power: 3w Light Color:  White 6000-6500K View angle: 120-140 LED support：Copper Life time:50000 hours Reds: http://www.ebay.com/itm/310834616296?_trksid=p2059210.m2749.l2649&var;=610229587957&ssPageName;=STRK%3AMEBIDX%3AIT DC Forward Voltage:2.2V~2.8V Forward Current: 600-700mA Output power: 3w Light Color:  White 6000-6500K View angle: 120-140 Any help and ideas is greatly appreciated. Thanks

Question by charles.terhune

### Problems with power supplies.

I made a small circuit board which is a proximity sensor that turns on or off a small philips genie light(its a small white tubelight like light ).i tried powering it up with a 9v battery and it works fine and the relay on the circuit board switches the ac220v load and the light goes on ,however when i try powering it up with a 10vdc adapter the relay on the circuit board keeps clicking(here i have not used the ac load to switch the tubelight,i was just experimenting and came upon the problem) .what should i do .pls help me.

Question by Strontium   |  last reply

### Power supply recommendation

I've been trying to collect info and guidance on how to build a portable and minimalistic power supply. I have in the past built other stomp boxes and small amplifiers (PCB kits) but never enough to learn how to read schematics or build from scratch, so I'm looking for something pretty detailed or simple enough. List of the technical and practical requirements: -Steady and safe current output for several hours straight; -Operating voltage: 3-4 to 15-17 volts; -Current: 2-3A; -1 voltage control potentiometer; -1 digital voltmeter; -1 output (1/4 jack); -1 pedal switch input (1/4 jack); -1 status LED; - Possibly external transformer (to keep it smaller and avoid overheating); -No vent holes; I have found similar builds (instuctables and YouTube), but never similar enough to be sure that putting that build in a smaller and sealed box would perform well and not overheat It seems weird to me that I wasn't able to find any kit or project for such a simple build. Below a link to an ideal result example https://thelondontattooconvention.com/suppliers/hard-craft-company-handmade-tattoo-power-supplies/

Question by circuitcircus   |  last reply

### 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.

Question by Icarus1990xx   |  last reply

### How to switch from AC power to battery power

I am putting my christmas tree on the ceiling this year. But I want to make it rotate. The only problem is to get the lights to come on I have to plug it into the wall. How would I switch the tree from using ac power to battery power?

Question by viv664   |  last reply

### 3 Phase supply

What will be configuration to supply 3 Phase 460 V power into these strings having voltage range as shows in the pics. It can be either star, delta etc configuration. It should be balanced. Answer will be highly appreciated.

Question by tverma95   |  last reply

### transformer less power supply?

I needed around 500mA current to run my mini project, so i decided to go through the transformer less power supply instead of normal transformer used supply.Since the other power supplies are quite bulky. But the problem occurred is, the supply doesn't supplies minimal current to run the project. Please, help me with this problem and suggest some alternatives or amendments to be made.  I have uploaded a picture of my design.

Question by ShuvamP   |  last reply

### i need a power supply

I am making chlorate's in a cell. but i need to give it about 5 volts and 1-2 amps. how would i do this cheaply?

Topic by DELETED_DELETED_kruser495   |  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:[http://www.radioshack.com/product/index.jsp?productId=3064080] Will this work?

Question by jfrazi10   |  last reply

### ATX power supply conversion

I know this is a long passed DIY. But while building a ATX Power supply I separated all the wires as stated. I then put the green and a black wire to a switch and added the 3 brown leads to the orange leads. When I plug in the unit the supply light comes on, but when I turn the green wire switch the main power LED goes out and no fan comes on. It acts like the switch is shutting the unit off.  Can anyone help. I am 60 years old and just getting into doing some bench work to pass the time. Thanks for any help.

Topic by Shorty954   |  last reply

### ATX Power Supply Conversion

Hi Again, My question is when building an ATX power supply, Can you join the 12 volt leads with the 5 volts leads to make 17 volts? If not how can I get lets say 20 volts. I am going to use a DC to DC converter to make a variable power supply. I would like at least 20V in then I can adjust from 1.2 to 60 volts out. I use it now running directly off battery but would like to add it to the ATX build case. Thanks for any help again.

Topic by Shorty954   |  last reply

### 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....

Topic by acer5050   |  last reply

### 48 volt power supply

Hello everyone. i am interested in building a power supply from 0-48 volts and able to push a good amount of amps. any one have a ruff idea on how to beable to adjust the voltage and not limit my current to 2 amps i would like to puch say 15-20 amps. i can build the rectifier i have a 600v i think 30 amp bridge rectifier. just not sure on how to do the adjusting without useing a regulator chip that only pushes a few amps. any help would be greatly appreciated.

Topic by omnacron   |  last reply

### DC supply for inverter

Hello. I need to figure out the component values for a "simple" high current power supply... and whether the component costs would even be feasible. I plan on buying a 3Kw output 12 DC inverter for use in Spain. I have several US devices that I don't want to run off a step-down transformer as running them at 50Hz instead of 60Hz will cause heating and eventual failure (I experimented with my Technics power amp, it got very hot and started to smell, then the output went way down... it's now on the "one of these days I'll open this up and take a look" pile). So, what I need to design is a 220 to 12 volt/300 amp unregulated supply. Ideas, anyone?

Topic by tsmyles   |  last reply

### convert ac to dc power supply?

Question by shailend   |  last reply

### 15 volt power supply help Answered

I need a 15 volt power supply. is there any other circuit than using a 7815 and two batteries?

Question by metsfan1938   |  last reply

### how to give power supply to a speaker?

I have spekers of an old radio in working condition...but to use it as my laptop speakers i need a power supply....so what would be its voltage, current and power ratings and how could i make it??

Question by navinn_11   |  last reply

I want to run my ps2 in car, Any circuit to drop 12v to 8.5V at 6amps the lm317 circuit is not powerful enough

Question by ARJOON   |  last reply

### 12v 20-30a power supply

Good day yall, i want to make a simple power supply to power up car amplifier, i have a transformer the trans former and is working with the kbu 606 diode, what type of regulator would be best to use and how much would i need, and if you have a diagram of something simple that can be adjusted then that would be great, thank yow

Topic by WIZZIEDEE   |  last reply

### What to do with free power supply?

I got this in the mail today from Allied (Free Sample) http://www.alliedelec.com/search/productdetail.aspx?SKU=9210079 SO...  what should I do with it?  Any thoughts?

Topic by RicoSPD   |  last reply