small DC 12v battery?

Hello all. i am currently working on an air powered rifle. my goal is for it to be self contained, so i took apart a testors airbrush compressor and i am fitting the compressor assembly to a 12v blower motor for an early 90s toyota 4runner. is there any way that i can make or purchase a 12v battery pack to power this thing?

Posted by dans89 7 years ago


How do I go about having a 12v battery power a device that runs off of 2x AA batteries?

I am looking to run a receiver that is powered by 2x AAA batteries off of a 12v 12ah battery that is also running an amplifier. If there a way to do this without burning up the receiver? I am looking for a cost effective way to do this. Thanks.

Posted by jgalvin1 5 years ago


12V car battery indicator

Hi, I have been trying to design a circuit to monitor my 12V leisure car battery, I'm thinking this should be fairly simple, but its been years since I did any real electronics. So the basic idea: Use the circular bargraph to indicate the level of the battery when a momentary push button is pressed the circular LED bar graph: https://www.sparkfun.com/products/11492 So the range of the battery would be something like 10.5V to 13.5V, there are 32 LEDs in pairs, so essentially 16. 1. So if we take the first LED pair, this should illuminate when less than 10.5V, so that should be easy, as long as there is some life in the battery it should illuminate 2. The next LED should only illuminate at the next step, 16 LEDs, 3V range 16/3= steps of 0.2V So at the following steps: 10.5, 10.7, 10.9, 11.1, 11.3, 11.5, 11.7, 11.9, 12.1, 12.3, 12.5, 12.7, 12.9, 13.1, 13.3, 13.5. So for 10.7V I guess I should use resistor before each LED. 3. The LEDs should light up after a momentary push switch is triggered, I would like this to be graceful, so the ring lights up smoothly one LED at a time as the voltage increases, I guess capacitors between the resistors and LEDs? This is the simplest way I can think of doing it, I have seen circuits which use a LM339 chip, but that can only monitor 4 voltages, perhaps 4 of these in series could do the job? http://www.electroschematics.com/7068/lm339-lm239-lm2901-datasheet/ I think this is the way to go rather than using inline resistor/ capacitor pairs? So I am a clear novice when it comes to electronics (but I'm enthusiastic), so if anyone can help me with this I would be more than happy to put together an instructables how to, something similar has been done before: https://www.instructables.com/id/Car-battery-tester/ In that example only one bar is lit, I want the other bars to stay lit. I can use Eagle to make the PCB diagram and get it printed, but I need to figure out what components I need and how to do it! Thanks for any help. Gary

Posted by garynobles 5 years ago


18v to 12v

Hey everyone, i need help on downgrading 18 volt battery to 12 volt battery, id like to do it for cheap or even free if thats possible. 

Posted by sirus17 8 years ago


5v to 12v convert

Hello, I want to connect a portable solar powered rechargeable to 2 DC fans of 12v to cool my car. 1. I have 2 options of portable solar powered: (A) 1500mAh, outputs: 5.5V / 800mA (B) 2000mAh, outputs: 5V 500mA     which one is preffered to connect to those PC fans? 2. most of the PC fans are working at 12v. I don't quite sure if I'll build simple 5v to 12v regulator it will works and produce enough airflow. Thanks.

Posted by ashakif 6 years ago


Small 12V batteries

I'm trying to make a simple LED circuit with switch included in the circuit. Can someone suggest to me a 12V battery that is big enough to keep a 48 LED bulb system on for at least 24 running hours, but small enough to be the size of two fingers sticky taped together. Thanks guys, Nick

Posted by kritas 8 years ago


load a 12V battery by the cigarete lighter

Hello guys, I want to make a publicity trailer with led's that will stand at party's (and on the side of the road in the week). This trailer will stand alone and will be powered by a 12V car battery. I would like to charge that battery while moving it with my car by a long cable to the 12V socket in the car. Should I place a resistor to limit the current or is this not necessary? The trailer is for my youth movement. (sorry for my bad english) Grts, Dieter Belgium

Posted by DieterD4 1 year ago


Question about low voltage power supplies

I have several wall plug power supplies. The voltage on one says 12v 300ma but on my multimeter im getting 17 volts. Why is it 17v and not 12v?

Posted by Rob K 10 years ago


5v to 12v step up

Hi, I am looking to power some led's by USB. Problem is that the led's are 12v. Here are some example led's: http://www.ebay.co.uk/itm/12V-SMD-1M-60-LED-STRIP-LIGHT-RED-HOME-AQUARIUM-CAR-/290571186666?pt=UK_HomeGarden_Lighting_Lamps_Lighting_SM&hash;=item43a76471ea#ht_3932wt_1396 Would something like this do what i want it to do?:http://www.suntekstore.co.uk/goods.php?id=14002311&utm;_source=gbuk  Also looking at the step up booster i have no idea where i would solder/connect wires to the device? Any help would be appreciated. ItzMar

Posted by ItzMar 6 years ago


Convert AAA battery power to 12V jack?

So I figured out a really good option for my external rumble pack I want to make, I see these Wii lightguns use X2 AAA batteries and have a micro switch that engages the internal rumble motor on the handle of the gun. The batteries are connected to a microswitch and the switch is pressed after the trigger is physically pulled. How can I convert the AAA batteries power method into an external 12V power connector for continuous use and stronger motor vibrations etc? Like I said this is my first DIY thing. I want the AAA battery method to be converted to a stronger more capable 12V. I plan on buying some strong force feedback motors that need 12V. Eventually adding a small Solenoid too.

Posted by JonathanH248 9 months ago


inexpensive high AmpHour 12V rechargeable?

I'm  looking to build a battery-powered speaker system for use on job sites, that will need to be louder than the equipment being used. For this purpose, I plan on using a tripath amp and some pretty decent speakers I have lying around, but the tough part is power. I need between 12V and 13.6V, with a relatively high AH rating. I considered a car battery, but don't want to have to trickle charge. I considered a Power Wheels battery and charger, but I've been seeing bad reviews on lifespan Any thoughts?

Posted by gschoppe 7 years ago


converting 110v christmas lights to 12v

In a web search looking for 12v Christmas lights to run off my small solar system, I found this; http://www.fly.net/~thundt/xmas12v.htm This looks very straight forward and easy enough to do.Has anyone here tried this?I bought a small set of solar powered at Target ($14.95). Way under powered and last only a few hours. It's going back today!This looks like a way to get brighter, longer lasting lights and I don't have to run my converter. My 160 AH battery should power it up nicely, I would think...Think I found a project for this afternoon!

Posted by olddawg 9 years ago


Any thoughts on this method to power a car stereo?

OK, I've seen several posts of using computer power supplies and 12V wall adapters to power car stereos.  I was about to recycle an old portable cd player when I noticed that the power rating was 12V.  I haven't cracked it open yet to see how the power supply is wired, but could the power supply from this stereo be used to power a car stereo? 

Posted by RicoSPD 2 years ago


12v Portable Led lighting Help

I really need some help trying to power these led lights onto a portable table Im building.I need the power supply to be as small as possible. I honestly have no idea what Im doing except that i need a 12v power supply.I work on cars and custom put in leds all the time but the power supply always comes from main car battery.I have never tried to power them before from a small battery like AAs before for example. If anyone has any ideas please respond because I can not finish this project until I get the lights to work and I don't want to go wasting money buying stuff in the wrong places. I will also include a link to the ebay page where I bought the lights. Another thing is I have done research and cant find what the amps they draw are.  

Posted by godfather29 2 years ago


Making a 12v or 18v (Volt) Battery

I am working on a project with my dad (36 volt powered Go-Kart) and we can't afford any fancy batteries or any at all. I found a solution on Youtube where you could make your own 12 volt battery by using mason jars, sulfuric acid, and lead but that sounds unstable and not powerful enough for our project, and even then that's only 12 volts. So, what i am asking is: Is there any way i could make my own 18 volt batteries (2x to make 36) that are stable and  powerful enough to power something like a Go-Kart?? (Go-Kart is 25-30lb as of right now) Note: My options are: 1.Run 2x 18v batteries in parallel. 2.Run 3x 12v batteries in parallel.  3. And any other voltage that can be combined to make 36 volts... Thanks in advance!  :D

Posted by SullivanS 1 year ago


LED strips design?

How are these LED strips wired? I know they must be in parallel but what kind of resistors and how many LEDs per parallell? If anyone has a diagram of a good layout on how to string up 48 green LEDs with a 12v power supply, it'd be much appreciated.http://cgi.ebay.com/300mm-Flexible-Led-Strip-w-30pcs-Green-Leds-Extendable_W0QQitemZ200170044029QQihZ010QQcategoryZ66949QQssPageNameZWDVWQQrdZ1QQcmdZViewItemandhttp://cgi.ebay.com/48CM-PVC-LIGHT-STRIPE-STRIP-IN-48-LED-BULB-LAMP-GREEN_W0QQitemZ300169468922QQihZ020QQcategoryZ66949QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Posted by mrshow555 10 years ago


Modifying ATX Power Supply for 12v Power - Easiest Method?

I'm building a small box with toggle switches on it. I want each toggle switches to turn on something simple (mostly just LED lights). I was trying to think of how to power the box, and I thought about using an old atx case power supply since I've got an old computer I could pull it out of. I'm seeking advice because I have no experience with wiring at all.. and I don't want to burn the house down. :) If I jump the green and black wires on the motherboard plug so that I can turn on the supply, couldn't I just buy a simple molex Y-splitter and plug it into an available molex plug, and then cut the yellow and black wires and use those for the power and ground? Here are the Y-splitters I'm referring to: http://www.amazon.com/Computer-Molex-Power-Supply-Splitter/dp/B001PI9AAC Cut off the plugs from the Y, and run the yellow and black wires to my switch and then run a power wire from the switch to the LED light or case fan or whatever I'm powering off of that switch. The switches I'm using are 12v automotive toggle switches. Would this provide the power I need? Would it be too much power? Should I put in an inline fuse or a ohm resistor or something to make it safer? I appreciate any opinions.. I'm curious if anyone has ever used a molex plug in this kind of way and how it worked. :)

Posted by dlister70 5 years ago


LED Power supply question

I've got an idea to build a LED light strip for some decorative lighting under a couple of shelves, but it's been more than a few years since I've used my GCSE-level electronics knowledge and I could do with a bit of advice regarding PSUs and parallel connections. I'm thinking of using  two banks of 10 of these LED packages powered by a wall-wart type 12v PSU.  If I wired the individual banks in parallel would I be right in thinking that that would be a current draw of 200mA per bank since each LED has a 20mA requirement, and if both banks were connected to the PSU in parallel I'd need a PSU capable of supplying at least 400ma?

Posted by megahurts 7 years ago


Two batteries on one charger...request for advice.

Need some advice... I busk using a Fender Amp Can and a head set mic. The Fender amp can is a complete unit with speaker, amp, battery and charger (15v 400mha). The headset mic I run off a separate 12v SLA battery. I currently open up the Amp Can disconnect the internal battery, attach the external battery and charge it, then put the whole unit back together. I want to make an external terminal to connect the external battery for charging and this should be simple enough says I...hmmm...So I am canvassing for second opinions regarding possible problems and whether I should set the batteries in parallel or series? The Amp Can is an awesome little unit and Fender have stopped producing them so I don't want to do it any harm. I know I could just buy a separate charger for the battery but that would be more crap for me to carry and I don't have the $25  to spare just now...it would also be lame... Thanks for listening, Luke Some specs on the Amp Can: DESIGNATION TYPE PR 327 PART NUMBER 022-1270-000  (100 V) 022-1200-000  (120 V) 022-1230-000  (240 V) Aust 022-1240-000  (230 V) UK 022-1260-000  (230 V) Euro POWER OUTPUT 14.5 W into 4 â�¦ @ 5%THD with fresh battery  INPUT IMPEDANCE > 1 Mâ�¦ both channels INPUT SENSITIVITY 500 µV@ 1 kHz - gain switch in GUITAR 20 mV @ 1 kHz - gain switch out INPUT SENSITIVITY 5.7 mV, 1 kHz MICROPHONE SPEAKER 4 â�¦, 30 W Special Design 6” speaker w/16 oz. magnet and paper coil former (P/N 050543) DIMENSIONS Height: 8.75 in  22.3 cm Width: 7.75 in 19.7 cm Depth: 6.75 in 17.2 cm WEIGHT 13 lbs 5.9 kg Amp Can™ is a trademark of FMIC. Fender ®, Tone-Master ® and Twin Reverb® are registered trademarks of FMIC. Product specifications are subject to change without notice.

Posted by unpredictableTP 8 years ago


Car window motors

Hi guys, I don't know if I am on the right section for this kind of question, correct me if I am not. I am looking for a website that sells cars window motor, not the casing and everything, just the 12V motor itself. If anyone could help me, how many amps is there in the motor, I know its 12V, but I want the Wattage.  Thanks in advance!

Posted by bjaii 6 years ago


Multi- 9v or 12v outlet setup?

Does anyone know how to make or where to find a single wallwort (120v outlet) that has multiple 9v or 12 v out plugs? I've got alot of little electronics (mainly things that light up/ glow) and I hate all the blocks and power strips that I've got to use. (I'm in the US btw.) Thanks for any help! The Atomic Soul

Posted by TheAtomicSoul 10 years ago


Electric mower

I want to convert my old gas mower to an electric mower. 12v batteries are easy enough, and there is plenty of info re solar charging systems. I'm stuck on sourcing the motor. I was wondering if a car starter motor would be sufficient for running a lawnmower? It's a 12v motor, has enough oomph to turn over up to 12 cylinders of american steel, and there are plenty of 'em out there in junkyards waiting to be recycled. Sounds good on paper. Anyone have any insight into why this is or ain't a good idea? Thx- Rev. Bucky

Posted by RevBucky 10 years ago


Please Help Electrical question 12v LED wiring.

So I have a black wire and a white wire coming in to where I have to hook up this LED transformer I know this is 110v. I saw the circuit breaker and it was double pole so I assumed it would be a 220v I ordered a transformer that could handle 110 and 220 but the colors are different. Is the transformer shown meant to have input wires connected to the hot? which ones to I put where? What goes to white here and what goes to black?

Posted by seanrforrest 3 years ago


How to make 12V 2 switch touch panel for car?

Hi guys, I am looking to make a 2 button switch panel for car. I'd like to have capacitive buttons rather than ordinary switches if possible. Something similar to this but smaller and only 2 buttons 1 button needs to be momentary as this is an external power button wired into tablet. 1 button needs to be latching (press for on, press again for off) this controls the accessory power (amp/usb hub etc linked to this) I would like to have them backlit and behind some acrylic so you can just see the light but activate the switch. The capacitive touch buttons I have seen so far all seem to be under 5v and I'll need to work with 12v since it will be inside car. Any help on this would be greatly appreciated 

Posted by alexmallaburn 9 months ago


Converting 12v DC to 5v DC

Greetings, I’m very new in electronics. I would like to connect my analog camera that uses 5v dc to my car battery. So I need your help to make a voltage converter. From what I have understand searching the web, I will be possible and very easy actually. All I would need is an opamp and some resistors?!!! Right? So any diagram or anything that you can help me with will be more than appreciated. Thank you for your time reading this. Best Regards P.S. I hope I’m in the right place writing this topic  

Posted by toqilula 7 years ago


12V LED to Battery Power?

Hello! I'm just getting my own cab company started in my medium sized town, and to begin I'll be using my personal vehicle - thus, I'm using items I can remove so I don't get harrassed on my days off, such as magnetic decals and a magnetic top light. My question is this: Is there a way to convert a 12V, 96 LED light over to battery power? The toppers use a direct cable to a car charger port, but I hate having that cord just hanging out in my cab. It is tacky and unprofessional - at the same time, I very much do not want to punch holes in the top of my car and wire it to my dome light. I have found several rechargeable, compact 12V batteries online, but I've no idea how I'd hook them up. I'm smart enough to know that I can't just wire it directly to the device - the battery would last minutes at most. I think I'd need some kind of transformer, perhaps? Any suggestions? And here's the battery I would use: Voltage: 12 Lead Acid Type: General Purpose Capacity: .8AH Chemistry: Lead Acid Lead Acid Design: AGM Product Category: Sealed Lead Acid Terminal Type: WL, Wire Leads Weight: 0.8 lbs Length: 3.78 in Width: 0.98 in Height: 2.4 in

Posted by NiteRide 1 year ago


Need help building a scoreboard with arduino 101 and 12v LED strips

SOS HELPP! Im trying to build a scoreboard with 12v led strips, large digit drivers shift registers (TPIC6C596) and arduino 101 but im not sure how to build it. i have used this drivers before in a 4 digit  clock and the drivers based on another project i saw here in this page, but im not sure if i can use them for the scoreboard.This arduino 101 has a bluetooth componet integrated and im planning on using it to control the scoreboar via bluetooth but if can come out with an other idea it will be great, but i have very limited time and parts and im kind of new to arduino and the whole poject stuff. if you can help me with anything ill be very thankful.. here its the link for the drivers https://www.sparkfun.com/products/13279

Posted by kahboni 1 year ago


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???

Posted by Shezi007 11 months ago


Powering 12v LEDs from 12v Deep Cycle Battery

Hey all, I'm trying to power some 3528 LED strands to hang from a shade structure I have outside. I picked up a 115 Ah 12v deep cycle marine battery, but I just wanted to make sure I could wire them directly to a distribution block without blowing anything up. The strands draw 6A of current so I was going to find the closest fuse to that value (10A?) to prevent any chance of overpowering the control boxes. Does this seem correct? Image shows roughly what I'm trying to do (black boxes around red wire are fuses, 1-3 are the LED control modules) Greatly appreciate any help!

Posted by synaptech 5 years ago


12V DC to 220V AC supply

Hello I have a emergency light with battery back up. its lights have gone out so i want to use its 12V dc power to transfer to ac power to backup a media converter, wifi router and mobile charger. Please, i want a detailed process of building this system. how much time could i get backup? i need a instrument and parts list for this project. i have uploaded the pictures of my light and specifications along with it. thanks

Posted by energyworks 4 years ago


Help , electric current from adaptor question

Ok kind of a noob question .. so im running 4 12v dc fans using .28 A current in Parallel with an adaptor that outputs 12V with .3 A current. my question is, will i need to add something (resistor or w/e) to limit the current  so my fans dont fry or will i be ok with nothing?.. i also want the voltage to remain at 12V , because i need them running at full  I searched the forums, couldn't find any specific answer Thanks for your help!! -Chris

Posted by cholborn 7 years ago


12V DC to 220V AC

I have an emergency lamp with backup battery power. its lamps have gone out. i want to use it to power a router, medai converter and a mobile charger. i have uploaded the specification of my power supply and things i want to run. please give me a detail way of doing this project and the materials i need, like inverter and other things My lamp gives 12V DC supply. i want to convert it to 220V AC and run those components. how can i run it and how long can i run thanks

Posted by energyworks 4 years ago


Timer for turning camera off at night

Hello. I have made a solar panel-powered bird box camera, and need a way to switch it off at night. The 5W/12v solar panel feeds to a rechargeable 12v battery. The 12v battery feeds to a voltage regulator, which then feeds on to a 9v infra-red camera. This set up works well, but the camera is running 24 hours a day. This is draining the battery unnecessarily at night. Does anyone know if there is something I could make or buy, that would stop power from going to the camera from 10pm to 6am ? Thanks for your help. Cheers!

Posted by artworkmonkey 3 years ago


12v solar to heat water

Im looking to install a hot water cylinder with a 12v immersion heater powered by solar panels(to add wind later) to my hot tub. the idea is to either heat the whole thing all the time or to at least reduce my power usage on the heat side of the running cost. has anyone done anything like this and have any advice? the basic install idea i have is, solar panel/s to a controller controller to a battery controller to immersion heater was also thinking of installing a normally open relay onto the stat of the heater so when it is at temp a fan heater would kick in, but that would be a later install if the water heating would work. any info would be great, if i get enough info i will be doing this and making it into an instructable to further help adopt this to work better. thanks....

Posted by gareth.collier.1985 2 years ago


Adapt a computer ATX power supply to add a single 2 wire 12V connector

 I need to replace a 350W power supply that supplies a computer setup and LCD screen in an all in one computer. The failing power supply has one single 2 wire(one black, one white) connector powering a power board that supplys the power to the LCD screen. Can I use any ATX power supply that has the same or more amps on each of the 12V 5V and 3.3V and........ Can I adapt the spare 4 pin molex connectors to make a 2 wire single connector? I can take photos if necessary. hi, thank you

Posted by NickEloFun_1 7 years ago


Can I use this battery at the same time when charging?

Hi, I couldn't find the answer anywhere so i'm gonna ask - is this battery usable while charging at the same time?  http://www.ebay.com/itm/Good-quality-New-DC-12V-Portable-9800mAh-Li-ion-Super-Rechargeable-Battery-Pack-/130693998479?tfrom=131459486190&tpos;=top&ttype;=price&talgo;=undefined I'm thinking about using this battery on my portable speaker with Lepai 2020A+ amp ..

Posted by Wauchy 3 years ago


Electronics dummy needs your input please

Hi, I want to run a battery operated item that takes its power directly from my 50cc mopeds 12v 4ah battery.  The item takes a minimum of 60w and can take upto 100w which I'm told, could drain the mopeds battery too much even when the engine is running at full speed charging the battery. Can I connect an adustable 6-24v step up inverter to the main bikes battery and use it to install and charge a second 12v bike battery purley to power the 60w to 100w electrical item while its in use, saving my main bikes battery to besure it won't run out of enough power to start the moped after Ive finnished using the electrical item? Im sorry but I not good at electonics and need your input to help guide me to run the item from my 50cc scooter/moped.

Posted by selectauto 5 years ago


Easiest low voltage cutoff (ensure minimum startup amperage for solar fan project.)

So, if I weren't so electronically derped, I'd know this. I've seen a few easy ideas for a 12v solar fan.  Basically stick a capacitor on it. However, I'm trying to work from a few low amperage panels (~100ma@12v total).  Since I want this to keep my tent feeling cooler once the sun comes up, I don't want to be stuck for an hour or two in the morning until the minimum amperage comes out of the panels. Anyone have an easy idea of what I could use with simple parts from scavenge boards or electronics teaching kits to make it have a low voltage cutoff (so that it won't go to the fan until it hits a minimum voltage on the capacitor (so that it has a minimum startup amperage))  That way, even in the morning, at least it would pulse on for small whiles even when it didn't have enough power.

Posted by TheRevJester 5 years ago


How do I power these amps??

I've got these two car amps (see pictures below) that I was given along with the sub that some people already know I have. I was thinking it would probably be better to use one of these amps instead of the one I'm using now but I can't figure out how to power it. I know it's 12v obviously but I'm not sure what to use nor do I know how to get it on in the first place, as there is a remote wire on both amps so that it isn't on draining your battery (in a car of course) while the car is off, is there somewhere I would short this lead? Again, see my pictures below.

Posted by Punkguyta 11 years ago


6v to 12 v step up power inverter to charge phone from a 6v motorcycle electrical system. advice sought.

Hi, just below are two pictures and details of different mini 6v to 12v step up power inverters. I have tried to use the smallest sized one out of the two without success. I installed the smallest one on my old 50cc moped with the idea that it would charge my mobile phone as I rode my bike.  My bike has a 6v electrical system, hence the need for a 6v to 12v power inverter. I also bought a 12v incar charger lead from a phone shop. Its the type of lead you plug into your car cigerette lighter to keep your phone fully charged. It charges my phone well inside my car but not on my bike! On my bike. I connected the phone charger lead to the 6v to 12v step up inverter expecting it to charge my phone just as it would do in my car. But no! It does not charge my phone correctly. It seems to send power to my phone in short spurts and gaps. It will charge for 5 to 8 seconds. It then stops charging for 7 seconds and continues to charge for a further 5 to 8 seconds and the cycle repeats over and over. Having it charge this way means that the phone does not receive a good charge and eventually my phone battery goes low and then dies. I think there could be stability issues with this 6v to 12v power inverter. I have found another type of power inverter for sale. The seller says his inverter is quite stable. I may end up replacing the old inverter with the one. I'm hoping it will do the job more successfully than the current inverter im trying but failing to use. Im not technically minded. I have copied and pasted the web addresses of both inverters. On the sites you will see the technical details of both inverters. Would someone please take a look to compare both devices for me please. I am looking for a solution to charging my phone successfully whilst on my bike. Would the bigger inverter be better compared to the smaller one  I have allready installed? This is the inverter I am currently using but doesn't work properly.  http://www.ebay.co.uk/itm/350436684000?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2648 And this is the inverter I am thinking of getting to replace the old one.  http://www.ebay.co.uk/itm/DC-DC-Converter-Regulator-Step-up-Step-down-2-1-/150657732239?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash;=item2313e68e8f As i said, Im not techinally minded and and looking for your advice. Would the bigger inverter be a good choice to replace the old one to charge my phone. Thanks for replies in advance.

Posted by selectauto 6 years ago


Voltage regulator for laptop

Hi there. I have a problem for which I'd like some opinions: I have a PB laptop which has fried its inverter for the LCD due to the input voltage towards the inverter being too high (19v while it should be 12v and can only endure upto 13v). Most PB models have this problem. I looked around and some people suggest making a voltage regulator with a 7812 and some capacitors that gets its power directly from the input of the power adapter on the laptop (19v, 6+ amps). But since I am not really that into electronics, I have no idea if this will work, especially towards the heat that comes with the 7812, will it be high? The inverter needs around 0.5 amps input current. Others suggest a setup with (zener) diodes, but I have no clue how to start on that. Anybody have a suggestion? Many thanks.

Posted by .conne. 10 years ago


Help upgrading CFL circuit? Want to drive cfl's up to 25w.

Hello I have built this circuit, it can drive cfl's up to 15w, how do i modify it so that it can drive cfl's up to 25w?  I am using D313 for his project as the D882 didn't gave me the results i needed. Using 12v battery. Here is the original instructable link https://www.instructables.com/id/A-simple-low-voltage-inverter-for-fluorescent-lam/?ALLSTEPS (This question is optional) Do u think the transformer i made for this circuit can be used for the famous Jeanna's light (Joule's Thief). If yes then how it would connect on the circuit? I will be making two or three more transformers like this. Do u think it needs modifications for its working like number of turns for the primary, secondary and feedback, different wire gauge?

Posted by Clarkdale44 4 years ago


Running a fog machine and LEDs from battery pack

So I have this idea that will require a fog machine, some LED's, and a switch to turn them both on at the same time. The mechanical issues I have figured out, I just need a little help with the electronics. I plan to have this rig be mobile, as in backpack mounted, and I have no problem carrying a 12 volt battery on my back to accomplish this task. I need help on the specific electronics required in order to rig it together. To the best of my understanding, I need a 12 volt battery, an inverter/power outlet, and POSSIBLY a microcontroller, but I'd like to avoid the later at all costs, haha. Fog machine I intend to use would be 400 watt since it seems to be the most viable. If I can swing a KW one that would be awesome. And the LEDs would be either red or blue. I'd like a switch in the set up to allow for the fog/LEDs to be activated at the same time. URL to machine below: http://www.walmart.com/ip/Fog-Machine-400w/12335927 What I really need to know is how to set up the 12v to accept the 400w fog machine, if it's possible, and what type of gauge wire/cooling systems I would need if I chose to run this on my back for safety. And if you could help with the logistics of recharging the battery, that would be sweet as well. Thanks!

Posted by ItalianLou 6 years ago


Batteries and LED light modules - correctly powering for maximum life

Hiya, I need to power a LED strip of 3 LED lights with batteries. The LED box says it is a 12VDC light module, and on the back of the box it says the Input Power is 0.0453A. My limited understanding is that I should use a 9V battery plus 2x AA battery (I have limited space - a 8 AA pack wont fit inside my project)...is that correct? I need to know how long these batteries will last - if it is less than 10 hours can you suggest another way of powering it? I'm incredibly lost and very new to understanding all of this! Thanks in advance. 

Posted by SonyaS2 4 years ago


Carburettor Heater - need help

Hi All, Hope this is in the right section. I am working on a project to heat the body of a carburettor (Bing 84) in order to prevent carb icing.  No commercial solution exists for my carburettor.  My engine (for paramotoring) is air cooled so can't use water from cooling system. My idea was to strip out the nichrome heating element from a car cigarette lighter and use that.  The heat needs to be applied to the metal casing of the carburettor, preferably being hottest near the air intake side of the carb.  I decided the best place was where the air filter is attached - a 12mm long metal throat with a 35mm diameter The trouble is, I don't know I can transfer the hundreds of degrees of temperature from the nichrome to the metal body of the carb without just shorting out the battery.  If I am to have a layer of insulation between the nichrome and the carburettor, what can I use that will conduct heat but not electrical current, and withstand around 300 degrees of heat?  I also thought about reducing the current and spreading the heating over a larger portion of the metal casing, which would allow the temperature to be lower. I have also been experimenting with motorbike hand grip heaters that run of 12v but they don't generate enough heat - I need to be pumping in around 8-10A as the internal cooling effect of the fuel vaporising rapidly causes sub zero conditions inside the carb even when the outside air temperature is well above freezing.  I have a 7Ah li-ion which I would only switch on when required (maybe have a latching push button on throttle control). It may not be doable but its an interesting project nonetheless and something I am going to play around with.  Any ideas? Thanks, Dug

Posted by dugaldcurtis 6 years ago


Car Heater/ Warmer

Hello I am Melwin from India I want to create a Car Can/ bottle Warmer/ Heater. My Basic Aim is to make hot water for preparing baby formula my baby when I travel with family in my car. This way I can avoid multiple stops for getting hot water. The commercial versions are available in the Market for a minimum of 3000 Rupees. It is very rare to buy in India My plan is to buy a 220 v 1000Watt Heating Element and cut it to suit to 12v When i measured one test setup with such a coil I get around 1.5 Amps per coil. I didnt have a thermometer to test how hot it gets. Since the car Cigarette Lighter supports 10A. I can easily Add 4-6 Coils of the same length in parallel. Also I can add switch to get different temperatures by adding up coil for each switch. 1-2 Coils = Warm. 3-6 coils = Heat. I dont want it to be a huge cooker. It should be able to heat up a glass (200 ml ) of water till 50- 60 degrees C) A higher version can have a Thermostat to cut off things as a safety feature. If this setup succeeds in boiling up water then I can also have my favourite cup nooodles when on long trips with friends I plan to make a small ceramic frame to mount the heating elemmet. On top I will place a Copper plate. Leaving some gap between the Plate and coil. This entire setup will sit in a Tin can of suitable diameter. I need to think about how i get the ceramic frame to Sit inside the can without touching the Metal. To this Metal can i will attach a handle so that it can be handled when hot. My next question. Where do I place it in my car safely. Suggestions/ Concerns/ Comments please Melwin

Posted by melwinmyworld 6 years ago


12V Monitor LCD display

I'm looking for a 12V display to monitor 12V as it changes. And display it in .1 increments. Small as possible. Can anyone point me to something cheap?

Posted by fasterthanyours 9 years ago


12v device to switch on a 9v device (signal to switch on only)

I have a device that is switched on by a sensor, powered by 12v, 1.3amp battery. I have another device that is switched on by a mechanical push button switch, this is powered by a 9v battery. I want to piggy back on the wires that switch on the 12v device and take the signal (to turn on only) to the device that is already powered by a 9v battery and normally turned on by a push button switch. ( I want to replace this mechanical push button switch with an "electronic switch" turned on and off the the presence and absence of the 12v signal) I want the 9v device to switch on only when the 12v device switches on and switch off when the 12v device switches off. Also I want the 9v device to only run on the original 9v battery (not accepting power from the 12v device and not returning any power from the 9v device to the 12v device. Is there a switch device/relay that can do this? A device that I can just connect between the wires going from the 12v device to the 9v device? I am a novice to electronics please be kind. I an open to using part from another device, and basic mods. Thank you

Posted by Jvos 6 years ago


Arduino 12V Car-alarm with PIR sensor and remote control - expertise needed. :-)

Hi all, This is my first "big" Arduino project and my first fritzing, so please bear with me. :-) Goal: - Build the cheapest possible car alarm system with a loud siren - It should be possible to activate/deactivate the alarm with a remote control. - The alarm will once activated, sense any motion in the car (if someone breaks a window and tries to steal anything) and set of the alarm. - The system should not drain the car battery so it should draw a minimum of power. I've managed to build the first few things, but some vital steps are still needed and I hope you can help me sort these out. Components used so far: Arduino Pro Mini - TIP122 transistor - 2.2KOhm resistor - 1N4002 diode - Mini piezo siren (I used a 107dB siren with an operating voltage of 6-15Vdc and current consumption of 140mA) - Breadboard - Lots of wires I'm currently waiting for my PIR sensor to arrive together with the RF receiver/transmitter module, so for now I've added a basic switch to act as the PIR sensor and another for the RF module (activate/deactivate). The components I'm waiting for are: - An RF module that I need to order once i find the right one. - http://www.ebay.com/itm/261041100836?_trksid=p2060... Questions that still remain and that I hope you can help me with: 1. The arduino should be powered by the cars 12V battery, however I've read that the car battery must be regulated as it delivers anywhere from 12 - 16V. I could connect it directly to RAW but in case the battery peaks above 16V i risk damaging the Arduino. I'm very unsure as to how I do this regulating best? One option could be to buy a "DC-DC step down converter - 4-35Vdc > 1,23-30Vdc" and set it to 5V, but maybe a more simple and/or cheaper solution exists? 2. Since the power consumption should be kept to a minimum, I plan to add the RF before the step down converter so the powering of the regulator (step down converter?) only happens if the alarm is activated from the remote. First question is: can I use a TIP120 for this and simply connect the RF to base, and the regulator to the collector? Second: In this case, the Arduino will be powered off the hard way by cutting power when deactivating the alarm from the remote - can the arduino take that in the long run? and finally, the RF receiver needs to get its power from somewhere, so what can I do here - is the best thing to use a 12V RF module instead of the Arduino 5V RF module or can this be solved some other way? 3. Any good ideas for minimizing power consumption? 4. Anything I can do to further improve the design? :-) I'll update this post as I progress with the project including a more detailed step guide to how to implement this and the source code I'm using. Instructables arduino posts and commets have helped me a lot during over the past few weeks working with Arduino so I hope you can help me reach the finish line with this project. Br. Jakob

Posted by Zyb3r 2 years ago


555 Car Flasher unit circuit

Hi, I'm wanting to put some led indicators in my car because they are so efficient but my current flasher unit isn't designed to run such a low load.  It is also relay based which probably isn't the most efficient way of doing things and with it being an old mini it sometimes rattles itself at whatever rate it feels like flashing at at the time so I wanted to use a transistor instead. I've come up with the circuit attached and built it but when it is running all the indicator lights for the hazzards, the transistor gets hot! Surely there is a better way of doing it? Could someone have a look and see what could be changed? I don't know much about transistors but I know that I'd be better getting it to 'saturate' and act as a low resistance switch but I don't know how to achieve that.  It also has to run under two loads, indicators and hazzards, and has to flash at the same rate for each - between 1hz and 2hz. http://www.dprg.org/tutorials/2005-11a/index.html I think a variation of this circuit might be better (it makes use of the discharge pin rather than the output pin), with the load at the ground side of the transistor because it has to be an output pin on the flasher unit. I've got some BFY51, BUY82, BD743B so it would be great to use one of them. in short: what's the best solid state fixed rate 12v flasher driver using a 555 that can supply around 2 amps using as few parts as possible? Thanks for your time, and sorry if I've done anything wrong!

Posted by arichardson 6 years ago