Im kind of interested in messing with some basic electronics (which i know very little about) and my question is if I have 2 dc devices that have a 900ma draw on both like 2 cell phones .... do I need 2 separate circuits that can handle the individual loads or do i need 1 circuit that outputs say 2a they both take what they need from?

Topic by cbubel 4 years ago  |  last reply 4 years ago

solar cell amperes

Lets say I have a solar panel that gives off 5 volts at 30mA. if I were to put a ten ohm resistor in series with it would There be basically no effect because a 10ohm resistor woulkd limit it to half an amp, which is way more. Or does the solar panel act like ~ 167 ohm resistor, and adding a ten ohm resistor will limit it to 28mA?

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

Supplying amperes on fan? Answered

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

Question by BIO Wolf 8 years ago  |  last reply 8 years ago

I need help with amperes !!

I don't know about ampere and I need help! can someone please give me some tips or something? please help!

Question by zhengguang 7 years ago  |  last reply 7 years ago

can i increase 200a to 5a?

Plz help me,, i have a 12v 200ma dc adapter and i need to transform it into 12v 5a dc it possible? i

Question by akhil s 3 years ago  |  last reply 3 years ago

what does peek ampere mean? Answered

Hey! Well, I have a 36v500w motor which requires ~14A basically. now i want to buy this controller: which states Dual Motor Driver Module board H-bridge DC MOSFET IRF3205 3-36V 10A Peak 30A so it is above 10A and under the 30A is it ok to constantly use it on 14A?

Question by benf3 4 years ago  |  last reply 4 years ago

how do you get from Ampere to Ampere hours? Answered

I know, basically it's not too diffy. I checked wikipedia and in the end i get to Coulomb, but the information i need is: i wanna build these cat-ears: and as material one needs a LiPo battery - the guy says "anything that will be able to supply 3A worth of current" and links to a 800mAh-battery at hobbyking. I first bought a battery with 4000mAh, say a battery that gives 4A per hour, but the one i got is quite heavy and i doubt that it's a good idea to use it in this light-weighted project - so how the hell did that guy get from a 800mAH-battery to the 3A worth of current? How do i calculate this way?

Question by Luziviech 6 years ago  |  last reply 6 years ago

Is a high ampere switch necessary?? Answered

I was going to try to build my now 2nd coil gun but this time wanted a solid state switch. after looking at the following: i was wondering if an 800A SCR is really necessary or can i just use a 16A SCR?

Question by MadScientist101 8 years ago  |  last reply 8 years ago

Question regarding LEDs and Amperes? Answered

Hi guys,             I want to build a project which has 3 blue leds which will take in almost 9 v. I could just use a 9 volt battery as it would be cheaper and easy but I want more mAh. So I have a few questions regarding if I use 6 AA batteries instead. 1. All of them connected (+ to -) will give me approx. 2500 mah and 9v right? And as 3 LED's would take about 3v 20 mah each, how much run time would 6 AA batteries give me? 2. How much run time would I get with the 9v battery? As it is only 400mah I think Thanks in advance -A Prickly Potato

Question by The Prickly Potato 4 years ago  |  last reply 4 years ago

Maximum/minimum ampere input in a circuit, help needed.

To start of my question im going to say i don't know a lot of electronics and that I am norwegian( so please excuse typos in english) :) I have not done many major projects inside the field of electronics other than making a lightbulb light up. using a battery and to wires.. But I am very interseted in electonics ad think it is very exiting to read about.  As my first "real" project i decided to make a "lie detector", altough it is mostly just a circuit that measures the resistance in your skin and makes a beeping sound after how much resistance your skin has( Dry skin = low resistance vs wet/sweaty skin = much resistance). AND I DID IT! i made it work, and i was so proud! Then I realized that it was actually kinda lame and the beebing noise was wery annoying. So I decided to make a display that displayed a value after how much resistance your skin held. I managed to make a seven segment display from scratch. But now I am stuck... You see the circuit gives an output of amps so it will output more amps on wet skin than on dry skin. But I have to "program"  the circuit to make the numbers on my display change. I want preferably to be able to do this without any IC's. So my question is there possible to make a circuit that will allow current to pass through one circuit, but if the current is high enough it will take another way? I tried to use diffrent resistors, but I didnt take into count that electricity only takes the road of least resistance no matter..

Topic by VetleH 4 years ago  |  last reply 4 years ago

Do Amperage Ratings Add in Parallel or Series? Answered

I was wondering if the amperage ratings of devices, say, for instance, circuit breakers, add in parallel or series. For example, if I hooked up 5 20 Amp circuit breakers in parallel, would it take 100 amps to trigger them all? Or would it take 100 amps with them in series to trip them all? I'm not sure about this because I have used two 1 amp solid state relays in series to switch loads well above 1 amp, but it seems more logical for them to only do that if they were connected in parallel. Also, whatever the answer to my question is, does it apply to all devices? Circuit breakers, Triacs, etc? Thanks!

Question by mad magoo 9 years ago  |  last reply 9 years ago

How can i increase amperes ? Answered

I am making a college project for science fair, and i have made a generator with DC motor of 24v, 0.33 amp and 7.92 watt. When i rotate the motor it gives 24-27 volt of dc voltage. Now i want to convert that DC voltage into AC by connecting a converter of 12 volt, 7 amp. I have made i rectifier which converts the 24 dc into 12 dc voltage, but when  the converter does not start. Can you please tell me what may be the faults? If the apms  are less, can i increase the amps? If the amps are 0.33 can i increase them to 7 amps?

Question by RobbyS13 2 years ago  |  last reply 2 years ago

what will happen if i give dc 12v and 5 ampere to 2000watt inverter , how much ac ampere should it produce ?? Answered

I now what inverter does it convert dc to ac , i also know that it can convert dc 12 volt to ac 120 -110 volt but  the thing from which i m confused with is that what will happen to the ampere for example i have a 12 volt 5 ampere battery if i plugged the battery to 2000 watt inverter should it produce 2000 ac watt with just 12 volt and 5 ampere battery or i have to give more dc ampere to the inverter................ means can inverter    convert dc less volt to ac high volt  and  with also convert dc less ampere to ac high ampere   or will it convert  dc low volt to ac high volt without changing the dc low ampere and need more dc ampere or will it convert dc low volt to ac high volt with decreasing the dc ampere....

Question by MuhammadK19 3 years ago  |  last reply 3 years ago

How to transform 12v 6w into 5v 1A?

Question by Davadivo 3 years ago  |  last reply 3 years ago

Combine 2 powerbanks for mobile

Hello, I have 2 old powerbanks that didn't have enough cappacity. So I want to combine the 2. But both have 5v 800ma output. So if I am afraid that the voltage or the ampere will be to high. How can I combine the 2 without damaging my phone? Sorry for my bad english. Greeting, Thijs

Topic by Thijsd4 3 years ago  |  last reply 3 years ago

how many voltage means one ampere? or how much voltage equal to 1 ampere current. how to convert it.?

Please tell me convergence of voltage and current. how much voltage equal to one ampere?

Question by sonambekar 6 years ago  |  last reply 6 years ago

how could i use the energy of my energizer 15 minute AA/AAA for another application?

I was hoping to hook this up to my hydrogen electrolysis cell for some experimentation.

Question by GalaxyX 9 years ago  |  last reply 9 years ago

What's the Difference Between Watts, Amperes, and Volts?

I always find this really confusing. Also I have a MotoMaster 12v solar panel supposedly for a car or something from Canadian Tire but I got it for electronics projects. I can get a voltemeter to detect voltage coming from it but I can't get it to work a motor or light or anything. It has two normal alligator clip leads.

Topic by Aeshir 12 years ago  |  last reply 12 years ago

How many Volts and Amperes can arduino handle?

Hello! I'm totally new to electronics and adruino's. Please forgive me for stupid questions. I have an idea how to make dawn simulator with LEDs. I plan to use a lot of them, 300-500 from first draft. LED will be in white, yellow and red color, 5mm. I thought to use 12V, ???A adapter (maybe form 12V halogen lights). LED will be connected in serial and parallel combination. So, my stupid questions are: Can arduino work with 12V? How many V's A's can arduino handle? I need those answers for start… If you can help, please do :) Thank you!

Topic by davor07 7 years ago  |  last reply 3 years ago

how to power multiple fans from a laptop? Answered

I'm currently working on a laptop to somewhat of a desktop conversion.  The laptop has really bad cooling so i have drilled into the case and added some big fans.  Its probably overkill yes, but if it works then who cares.   I've added two fans.  One is a 24V DC .20A fan and the other is a regular DC motor.  I'm wanting to power them from the laptop.  I'm not sure how to do that though.  I've tested them both separately on a USB and they are very slow and almost useless.  Is there a way to combine two USB ports for more juice?  Any ideas or suggestions?  Thanks.

Question by knex.gun.builder 5 years ago  |  last reply 5 years ago

Making a better spot welder....

I am in the process of building a proper spot welder from scratch. Proper more in terms of the electrical and electronics part but not so much in looks ;) My problem now is to find useful info on what power levels are required for certain tasks. I realise that welding thin sheet metal won't need as much time and amps as welding a 3mm stainless steel rod - but what is a "good" power level? I watched a bunch of Youtube videos showing various approaches but for many it seems the producer had no clue about the difference between creating a short with burn marks and a weld... Especially when it comes to creating battery packs with a capacitor bank as the main power provider you can clearly see the device burns holes but does not really create a welded spot. On the other hand there are a few videos showing spot welder made from a MOT that seem to produce a proper melted and welded connection. When I used a proper spot welder at work it had timing settings, power levels and even a feature to adjust how the current rises.... Not to mention a gauge that checks the pressure and only activates the welder once the set point is reached... There is a ton of info out there that after a thausand words still tells you nothing you need to know :( So is there anyone here who can shed some light on the actual process of spot welding in easy words for everyone to follow? I am aiming for a max output of around 400A @ 1.5 -2.5V with an adjustable shunt in the transformer core to avoid oversaturating the core. In a later stage I will add power control over the primary side but until then it is only time control, from a few ms to a max of 5sec if the damn controller arrives one day. Big questions: 1. Is a power control really required or is it possible to cater from thin to thick just by using different timing settings? 2. Since a MOT is used for the power supply: Is it better to leave the shunts out to fully avoid saturation by adding an inductor in line with the primary or is it still better to adjust the shunts under load to get the maximum power possible? 3. Aluminium and other materials benefit from using AC but would be good to have a DC output too, if so then what materials really need DC? 4. All I could find is that copper is used for the electrodes, due to resistance and heat transfer - are there other options apart from using copper? 5. Tricky one: I would prefer to use the secondary winding as the new primary to avoid core saturation and to lower the load on the power outlet. Where can I find very thin copper bar material that I can coil up and insulate as I would quite a few more turns to get at least 1.5V out of it? Just don't like the idea of spending days rolling a copper bar thin enough.... For the advanced model at a much later stage: Of course I would like to be able to use a proper power control instead of a motor dimmer or similar. For obvious reasons an inverter microwave jumps to mind. But after checking one I noticed one big problem: there are not really that many windings on the primary of the transformer at all! Same way our modern switchmode power supplies only use a few turns these things do exactly the same. After some quick and dirty initial tests I realised that even a single turn of thick wire already results in over 20V on the secondary. Wasted a lot of wire and time making one coil with 5 turns less and one with 10 turns less but the system would not even start with it. Seems these things need a fixed inductivity on the primary that matches the frequency used, in my case 36kHz. Would love to overcome this problem so I can at least go down to a single turn to get under 5V on the output side as space is non existing on these inverters. Can I cheat? Do I need to change the circuit to match the new primary coil? Am I thinking in the wrong direction altogether here? And added bonus would be to be able to adjust the power from around 15% to 100%, so far the electronics don't allow anything below 45%. Is it possible to drive these inverters in resonance? (Ok, off topic as I would like to use this for a beefy HV supply) Last thoughts: I know people already used Arduinos and Raspberries with displays and all but so far I have not found anything that shows how to do it properly. Seems all that counts is to create connection one way or the other and to call it a spot weld even if it is just a burn hole from discharging a capacitor bank through a needle like electrode.... For obvious reasons I don't want to create just another spot welder that makes a professional pee himself laughing about it. IMHO nothing beats personal experience with something but I don't really like wasting my time by trying what other people alread did a long time ago. So if YOU already built a MOT based spot welder and used for more than a few spots I would love to hear from you! Let me know what type you used, what problems or shortcomings you noticed or where you feel it just does not work out the way you expected it. From simple things like always getting bad sparks or arcing, over how easy or hard it is to get consistand results to whatever really annoys you while using your homemade spot welder. I hope that your feedback here will help me to write an Instructable on building a spot welder that does what you expect it to do, not once or twice, but everytime you use it. Mechanics might vary the same way the electrode style does but the weld should always be a proper weld that won't tear apart ;)

Topic by Downunder35m 1 year ago

Pararel connection Transformer

i want to combine two of 10 ampere Trafo, so i can have 20 Ampere power supply  i read a few article that say if we connect the sekunder(secondary) of identical Transformer in pararel, we can have a double time current flow on this connection. do anybody have try this before?

Question by beatobe 7 years ago  |  last reply 7 years ago

How to measure verry smal current (amperes) with multi meter?

Hi I'm trying to measure how much current can be generated from tomatoes. Please have a look at and my question will make a lot more sence. What option should i use ( 200u, 2000u, 20m, 200m) if i use 20 on the voltage and i want to use the formula W=VxA ? It seems to me that the measuring in itselfs alters the numbers. The brightness of the LED changes. What is happening here ? How can i measure amperes ? On the picture: 1/ LED hooked up to a battery. Multimeter placed in series to measure the current. (the LED seems to light up but this is reflection) 2/ I turn the multimeter to 200m, the LED lights up very brightly. On the display: 03,8 3/ Multimeter is turned to 20m, the LED lights up. On the display: 3,29 4/ Multimeter is turned to 2000u, the LED lights up. On the display: 1197 5/ Multimeter is turned to 200u, the LED lights up but not verry strong. On the display 1  . Thanks to any one who can explain this to me in clear language. This are my first staps in elctricity-land. greetings, Maaike

Question by dr zeezucht 7 years ago  |  last reply 7 years ago

How to increase amps?

I heard ampere could be increased by capacitor. If true then how to do it???

Question by simba1 4 years ago  |  last reply 4 years ago

Is it possible to increase motor speed by adding current?

Hi there, I want to increase my 5 volts cooling pad speed by hacking it. I've tried increase the voltage, but the motor died after next hours. I have a plan to increase the current without increase the voltage, but it's doubtful to be worked. Somebody got any idea? Thank you

Question by AthaariqA 2 years ago  |  last reply 2 years ago


In 12 volts 3 ampere battery, how many 12 volts led can i use to light it up(not a strip one)

Topic by xandera 5 years ago

Can i use a laptop charger whose input and output ampers are higher than my original charger?

My original laptop charger is not working can i use New charger whose input is 100-240v-2.4a (2.4a) 50-60hz and output 20v(20v)== 4.5a(4.5a) insted of my original cahrger whose input was 100-240v~1.7a 50-60hz and output was 20v(20v) == 3.24a(3.24a). As you see there is difference in input and output ampers

Question by AbdulR138 3 years ago  |  last reply 3 years ago

Differences between a 75 and 65 watt power supply? Answered

The problem is this: I found another laptop power supply rated at the same voltage but slightly different amperes and wattage. Specs: Acer 19 V 3.42 A 65 Watts (guessing due to V x A = W) HP 19 V 3.95 A 75 Watts I tested both and their voltage seems fine and nothing wrong with the older 75 watt power supply with two pongs. Will there be an issue with the wattage differences? And will the amperes be a problem if my laptop is rated for 19 V, 3.42 A?

Question by BIO Wolf 8 years ago  |  last reply 8 years ago


I have a problem...i want to charge my ipod with some batteries, but playing music while charging. is this possible? another question...firewire is faster (what the volt and the ampere?) than usb to charge ipod? thx

Topic by Pacca 12 years ago  |  last reply 12 years ago

3 volt voltage regulators?

Hi,I need a 3 volt voltage regulator,1 ampere(or lower).I tried looking for Lm 7803 but couldn't find it any local shops.Anyother alternatives?

Question by Adarsh_tronix 6 years ago  |  last reply 3 years ago

where can I find a power supply which has a 12 volts and 3 amperes output?

I am looking for a simple circuit diagram and the name of the devices to be bought

Question by belovebluesky 8 years ago  |  last reply 8 years ago

effecient charger making?

I wanna make a charger for 4v, 0.5A batery 1)just suggest me the value of capacitor and inductor for filter ckt 2) and wat ampere of current should be sent to battery for fast recharging (at safe zone

Question by electrical sniper 5 years ago  |  last reply 5 years ago

convert to watt?

I am thinking of buying a acid battery. Its specification says that it is a 12 volt one and it's AHC@20 is 200. Can anybody calculate the watt output. I am not sure but AHC stands for Ampere hour capacity. Thanks RajibAzam

Question by RajibA 4 years ago  |  last reply 4 years ago

Is it enough?

So,I've got 10000uF x 50 capacitors, for a total of 0.5 farads, the capacitors operate at a breakdown voltage of 75 volts, is that enough to power to run a railgun? if not, can i use a trasformer to pull up the voltage?

Question by Lord Lovaht 1 year ago  |  last reply 1 year ago

Is It OK For Me To Use This Transformer?? Answered

I have a few questions about my transformer that I scavenged from an audio amplifier. I assume this transformer was used to drive big speakers. This bad-boy weighs in at eight pounds and is pictured below. The coil has a resistance of 2.2 Ohms. Is that normal? The Impedance of the transformer @ 60Hz will be higher that 2.2 Ohms, right? The transformer was wired into the wall outlet (120V AC) with only a #102 (1000pf) ceramic capacitor and a 125V-6.3A fuse in series. that means that the power comes from the wall goes through a fuse, a transformer, a ceramic capacitor, and then back into the wall. The fuse was burnt-out so I am bypassing it for now. I fully intend to get one asap. The #102 ceramic capacitor either isn't working or limits the voltage too much so I am bypassing that as well. What is this capacitor used for? Some of the voltage levels that I am measuring from the outputs of the transformer are as follows: 5v, 30v, 40v, 60v, 80v, and possibly a 100v measurement. There are a lot of outputs on this transformer so it is hard to remember all of the voltage levels. Is there anyway to tell how many amperes I can safely draw from this transformer? (I have no datasheet and cannot find one) Thank you for taking the time to read my plight! I would really appreciate a reply! Thanks!

Question by jensenr30 7 years ago  |  last reply 6 years ago

Pico fuse help?

Dear all.. By accident (short circuit) the pico fuse  in my watt meter is blown . Could you help me to know value of ampere (ie: 250v 1/4 amp...) of this pico fuse. the dimension  and color code in photo please. In the time waiting your help can I used glass fuse for replace .Thank you so much

Question by lam 4 years ago  |  last reply 1 year ago

how much current needed for a bilc pump to operate, will it operate with say 2 amps 12v PSU? Answered

How much current needed for a bilc pump to operate, will it operate with say 2 amps 12v PSU? I have this pump, i can barely spin it by hand and it is not working by poering by a 1 amp psu, perhaps I demaged it while testing with 24v Ac . thanks

Question by celalboz 9 years ago  |  last reply 9 years ago

What is the normal range of a 3,5mm output? Answered

Hey everyone! I want to make a switch between three or more 3,5mm input jacks. I've found an instructables instruction on how to do this, I only don't know which switch to pick. It has to be a rotary switch. Now my question: what are the minimum specs (volts, amperes, switch current etc) to keep good sound quality? Yours

Question by dijh 3 years ago  |  last reply 3 years ago

Fun with rockets and planes. Answered

Okay. I am building a plane from scratch designs (will post about it when i complete it) and I am planning on having a booster rocket to well to boost it. The only issue i have is with my igniter system. What im curious about is, would I be able to use a relay wired to an extra channel on my reciver? If so, what relay would be best?  (voltage,amperes,etc) Thanks, Bud

Question by budhaztm 6 years ago  |  last reply 6 years ago

convert 12v to 14.5 v simple? Answered

Hello. i have an LCD monitor powered from AC, that i want to make to be powered by DC for use in my car. the monitor PSU , supplies the controller with +5v and +14.5v. and i want to power the monitor from a regulated 12v psu. my question is, how would i make a dc booster, from 12v to 14.5 v at 2 ampere? thanks in advance!!

Question by settra 5 years ago  |  last reply 5 years ago

building a portable lead-acid charger?

I have two lead acid batteries rated 6v 4.5 AH (is AH ampere? or ampere/hour) boast/equalize 7.2-7.5v float 6.75-6.9v max charge current 1.35A both my batteries are identical the question now is.. i want to build a charger for it and something to lower is current so some feature i want is  1) rechargeable by a simple plug in adapter (i have a 12v 4A ac-dc adapter) 2) output of usb voltage and current (optional adjustable current and voltage) 3)led indicates 4)optional: a switch to power usb devices directly from the adapter/bypass battery to extend battery life 5)around 5 usb out puts? i want to build this project cos i have the won batteries which are in good conditions but not being used in anyway.. i hope someone can help me with the technical specs..especially on the circuit diagram   have access to an electrical components shop but it does not sell chips so i need to salvage them

Question by michaelgohjs 8 years ago  |  last reply 8 years ago

Silver recovery from photographic fixer solution at home level.

I wa trying to recover silver from photographic fixer solution using home made electrolysis unit having 12v and 3 ampere DC source, small graphite, and stainless steel dinning plate, plastic container of 25 L size.  But, after 6 hours, i was unable to get  the expected more than 60gm silver. in fact i get nothing at all. Why it went wrong? what is wrong with the anode, cathode, power voltage and amperage, volume of fixer used, NaOH added---? With regards!!!

Question by dese 7 years ago

Cold fusion experiment

I have reproduced some experiments on Cold Fusion. not as a source of energy but how to blend a wire of iron from 2mm with less than 2 ampere or obtain gas fuel from the water and graphite (coh4) without using dozens of amps.Do you think may be is interesting to do an instructabels to the matter? are not my nventions!I have same video of this experiment on my youtube channe Almost all in Italian language.. but with a little explanation also in EnglishThe power supply that i use and the experiments can be dangerous.. I would not like someone to dye !

Topic by alessiof76 10 years ago  |  last reply 3 years ago

Increasing current for hho cell?

What is the simplest method for someone like me who has very little experience in electronics and a low budget, to achieve a high current output for a hho cell? This is for a hho cell and torch so the voltage must be low and the current must be high. Basically what Im looking for is a cheap and easy way to create 3v -5v together with 10-100 amps. Are there any specific household appliances that can put out this current? Not car batteries, car battery chargers or wall sockets. Also is this enough to kill you or just give you a bad shock?

Question by mitchells 8 years ago  |  last reply 7 years ago

Current Consumtion by a DC Motor?

 I am asking few questions EV related, more current related. Let a consider a dc motor rated 4hp at 24v and 2hp at 12v. So is there a way to calculate ampere draw of the motor at various loads.(like no load, full load, or any load). And if we know the full load current of the dc motor then can we calculate the max load for the dc motor. Next as the dc motor is 2hp at 12v then will this value be constant or will the motor be able to produce 4hp at 12v even rather than at 24v. And will a battery eg 50ah be able to supply more then 50amp.

Topic by flyingdutchmen1659 6 years ago  |  last reply 3 years ago

Diac Triac Circuit?

Hello all respectful members, I hope you are well and busy with learning hobbies. I want to have a Diac Triac circuit that can run on 220 Volts, 10 / 15 Amperes, 50 Hz. main line. This circuit can be connected to AC socket to cut off appliances at line fluctuations, and can be reset by a tiny push button when line voltage become steady. I request to provide me this circuit with components values part # Any one wants to send circuit direct to my email address will also be accepted I hope to get a positive response from participants here. Thanks for consuming your time.

Question by CREATIVE 10 10 years ago

How can I convert an AC motor to a generator?

So for a school project, I am required to convert an AC motor to a generator. Actually, it is a table fan of diameter approximately 10-12 inches, and runs on AC power at 220V 50Hz. I want to convert it into a windmill, but I'm stuck on the power generation part. So using materials easily available in a high school physics laboratory, how can I convert an AC motor table fan into a generator? Also, what would the output of the generator made in volts and amperes?

Question by diwakarchopra 6 years ago  |  last reply 2 years ago

How to power speakers with batteries without an inverter?

I have a powered speaker system that runs on 120 AC. I have the battery and the inverter but I know the speaker functions on DC and it has an built-in AC-DC inverter. So to use my battery, converting it to AC with an inverter and then the speaker converting it back to DC and all this process will result in a lot of loss of energy and cost me in terms of runtime.  I would like to know if there is a way of by-passing the built in inverter and connecting the battery directly to the speaker without causing harm? What I thought was using a multimeter, measuring the voltage and the amper output of the built-in adapter and buying a battery with the same numbers and connecting it directly there. What are the risks in there? because I don´t want to burn my speaker.

Question by queremosvino 4 years ago  |  last reply 4 years ago

Electricity for the challenged

I have a US plug AC/DC power adapter and need to get a European version. The specks on the adapter are input: 120VAC 60Hz 24 W and the output: 10 VDC 1400mA. I really don't have a clue as to what all these numbers mean but understand at a bare minimum I need something with a 10 VDC output. I've looked around at some shops and can find adapters that say 9v 1000mA and others that are 12v 1500mA. Do I need to get the exact voltage (I presume the v stands for volts)? What about the amperes ( I believe that mA is some increment of amperage)? Can I fudge the numbers a bit to save money and time instead of trying to get the exact configuration of the original adapter? Thanks for any help in clarifying this for me.

Topic by Crackpot 11 years ago  |  last reply 11 years ago

Is there a way to lower a photocell's resistance to amps? Answered

I am making a device which uses a laser to lower a photocell's resistance to the point where enough current can flow to begin spinning a motor. Unfortunately, the motor (4.5 V) starts off by drawing about .75 amps and once running falls to .25 amps, but apparently the photocell can only draw a lot less- the only word I've been able to find is that it typically draws about 1 milliamp, which is nowhere near enough. I have two questions- first off, does anyone know how many milliamps I can run through a photocell, and is there any way that is pretty cheap so that I can lower the amps drawn or the resistance of the photocell without stopping the motors?

Question by seraine 7 years ago  |  last reply 7 years ago