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what if your a kid?

Im a teenager and i dont have any tools

Question by AlexJ08    |  last reply

locksmith andover ma

Hi Myself Jim sammy an internet and marketing author and coach. I help others how and what to do to generate profits from their online business using article marketing, list building and production creation online.I teach them online the pros and cons of different internet marketing procedures and tell them what is best for their own site and what more they could do to get maximum traffic and thus maximum profits. I have described few of my Internet marketing procedures in Window Tint Riverview Florida, Surety Bond Definition, locksmith sudbury, Direkte TV, movies online free streaming See my other social profiles;=272

Topic by kara9865  

mA on high intensity LED?

I bought a couple of red "Coast LED Lenser" LEDs from Frys ( They are in the standard 5mm package, but they give no forward voltage and the mA looks a bit high, being without a heatsink . If anyone can tell me if it looks correct and not a misprint, i would be very grateful, since coast doesn't have them on their website anymore. Oh yeah, while trying to light one I ran 8.5V@4.5A (PS2 adapter) accidentally (forgot the resistor) and it exploded loud pop instead of melting or burning out the junction like the 3mm LEDs from ebay, if that helps. The specs.   Intensity :                       10,000 mcd   Directivity:                      15* (degrees)   Operating Lifetime:      Up to 100,000 Hours   Wavelength:                  620nm   IF30:                               mA   IFP:                                 100 mA   VR:                                  5V   PD:                                  120 mW   Topr.:                              -30* to +100* (degrees) I'm guessing the forward voltage would be about 2.00V +/- .20V

Question by LuciferTengu    |  last reply

Electronics Adapter Question about mA

Hi guys I have an electronic device requiring 50-100mA at 5V. I only have an adapter that is rated at 1200mA at 5V. Is it safe to use the adapter? Thanks

Topic by noneother    |  last reply

Help me fix ma zune!

I've got to fix this damn zune, there's no warrenty on it and all in all it's a piece of crap. The guy doesn't care that much if it can't be fixed. I've got shit webcam reference pictures. You'll see that the battery has the terminals connected to a small IC board with 3 solder pads on it, and a voltage regulator of some sort on the bottomside of it. The ribbon cable has 3 little metal spades that solder to those pads on the battery. There's voltage coming out of the pads (I don't have a voltmeter, just a tongue but that works just as good). When I've got the ribbon cable soldered to the battery and I touch the end of it to my tongue I can feel current, so why is it that only once in a while I get power to the zune? Like if I wiggle the cable around sometimes I can get a low battery symbol to come up and then it shuts off. I don't know why it's still showing a low batt symbol because I charged it and it feels like there's a good charge in there so what's the problem? I wanna get this fixed so I can play around with it, no I've never had the pleasure of a zune :p. Thanks guys for anything you can help me with. I was thinking maybe the IC came loose from soldering/desoldering the cable a few times, but it still appears to be stuck on the board pretty good. Well look at the pictures and decide for yourself. It's starting to look like I'll be buying a new battery, which apparently the ipod 30/60 gig batteries are the same size/amperage and can be used in the zune and at a low price of $14, I can probably get a battery that'll last longer than the factory one eh?

Topic by Punkguyta    |  last reply

Ideas for school X-mas holiday shop items? Answered

Out elementary school has a holiday shop ever year, when the kids get to buy items for their families. (.25-$1) I want to make some items to donate, but I am overwhelmed with ideas. They should be simple, cheap, and should only take 10 minutes (or less)  or so to make each. I can sew, crochet, paper crafts, etc.    Ornaments? Bags? Toys?  Thoughts?????

Question by domestic_engineer    |  last reply

what is a slovent solution thingy ma bobey?

(for science exam)

Question by leo rox ur sox    |  last reply

What gases are producded while maing charcloth?

I wish to make charcloth on my single burner propane stove using a tin can on my patio. My question is....will the gases be of a dense smoky nature so that everyone is calling 911? Or are they going to be of an inconspicuous water vapor so I can carry out the process in my patio without bothering neighbours?

Question by eagles_dare13  

What's the difference between Christmas and X-mas? Or is there none? Answered

What I said above.  Also, if there is no difference, then why do they come up with "X-mas" as a name anyways?

Question by DJ Radio    |  last reply

What is does 200 mA stand for on a power supply?

I am trying to figure out the amps on a power supply. It has an input of 120v, 60 Hz, 4w. Output is 6VDC, 200mA. I just don't know what the mA is.

Question by bbierbaum    |  last reply

How many mA does an Apple iPod Charger use?

I need to know how many amps the charger cable that came with my iPod pulls. Please help!

Question by ElectroFlex    |  last reply

Bd 241c VU meter from a 100 mA ammeter?

I want to make a VU meter from my 100 mA ammeter with my bd 241 c transistor. Is it possible in an easy way, or I 'm just spending my free time with my doing nothing? :D Please take into consideration that I'm a really beginner, so explain like this.

Question by Gernerakos    |  last reply

How to drop 9 volts to 3 volts at 32 ma

Hello, I am a new B here. I would like to use a 9 volt battery to power lights for my RC car. The led lights operate at 3 volts 32 ma. What size resistor will I need to make the voltage drop. Will this also control the current so I do burn up the lights. The lights are somewhat expensive so would like to get it right the first time. Thanks for anyone's help.papadewey221

Question by papadewey221    |  last reply

Cutting and re-wiring X-mas LED garlands (not strips) Answered

Hi, Has anyone had to deal with cutting LED Christmas garlands into shorter pieces and then rewiring-powering them? What should I keep in mind when doing so? As far as my electrical knowledge goes I should first inspect the voltage which is provided by a standard converter already on a garland and then measure the voltage with the load (garland) on in several spots to determine a single LED voltage drop. Then cut the garland to desired lengths and power it with appropriate converters. Is this right? What I don't understand completely however is the voltage drop. Given that this is a series circuit and the voltage(resistance) sums up - should I add all the single LED drops to find out the total drop and therefore subtract that from my supply voltage to find out the LED working voltage? Oh, and maybe I am simply wrong about the circuit being in series? Thanks! Raitis

Question by Raitis    |  last reply

Local members Brain Drain Cape Cod, MA/RI?

I'd love to make a lot of the things on this site but even more than that I'd like to meet members nearby and share ideas, who knows what could come of it! I'd love to make some friends who are interested in this stuff! If you live on or around Cape Cod or anywhere between here and Rhode Island, post here and let's organize a meetup!

Topic by JollyRott3n    |  last reply

Specific output of current? Answered

I'm getting a little more knowledge about current measured in mA, but it's still all confusing. From my understanding, your project draws the current needed out of your battery. If my LED uses 25 mA, then the LED will be sucking 25 mA from the battery. If I have two LEDs, then it would be sucking 50mA from the battery, thus reducing its life. So, based on that, how can wall warts have a specific output of amps? How can a wall wart put out 1000 mA? If you use a project that only takes 700mA what happens to the other 300 mA? What if your project use 1,500 mA? And. . . How do you measure the current being pulled through a basic circuit and your average 555 circuit? Thanks,  

Question by HavocRC    |  last reply

85 LEDs taking 20ma each individually wired with a resistor, what ma power supply is needed? Answered

For 85 LEDs each taking 20ma wired individually with a resistor off of a single 9v power supply I would need at least a 1700 ma power adapter correct??...I would probably go with a 2000ma one though just to be safe.?

Question by lamboboy732    |  last reply

Merry Christmas!

I wish all the k'nexers at Instructables a merry Chrsitmas!

Topic by jollex    |  last reply


Is' that nice

Topic by markjr    |  last reply

Is there a cheap creation to make a 110v 9-45 mA power system?

I am looking at three ways for this right now. My preferred long game is a solar cell block (minor one, i am not sure of the power output calculator cells have, but along that size I am guessing) that feeds into a digital sine wave form for my output ( low end of power is fine.) I need the sine wave chips to do the build on a +/-110 V wave then, but the ampere I need is ultra tiny by current standards. The total power of this concept is about 1 watt. Perhaps a amp limiter off a wall circuit second as my second but probably easier choice. Reading up on some interesting theories, but to test them accurately, I need this base component(s). I will post the results of what I do with the device pas or fail, as I think it will be important to some of the current over unity power system theories bouncing around to have good well documented answers.

Question by JBrenton    |  last reply

Solar specification for Micro RC Car?

I want to develop micro solar rc car, but I'm confused about Volts and mA on the solar panel.The micro rc car recharge through the remote control and the remote control use 3V (Two AA batteries). So, what Solar panel volts and mA should I use? Thanks?

Question by ample    |  last reply

Would a 18.15 mA, 3.2 V solar cell have a strong enough output to charge 4 1.2 V 400 mAh batteries? Answered

I'm currently working on a project that uses 1 Solar Yard Light cell to charge up 4 SYL batteries and am not sure if the cell, (rated at 3.268 V and 18.15 mA), would be strong enough to charge up 4 SYL batteries. The batteries are rated at 400mAh capacity; Fast Charge Rate is 400 mA; Standard Charge Rate is 80 mA. Also, could I just wire the cell directly into the battery pack or would I have to wire it into the circuit board that came with the solar cell? Any help on this subject would be very much appreciated! :)

Question by BucketBasher    |  last reply

How can I use a 9volt charger on a 3.6 battery 700 mA?

So Im doing this project where I have a 9 volt charger and I need to charge a 3.6 volt 700 ma battery. How would i go about charging this battery? I tried to use one resistor but it got extremely hot, hot enough to melt plastic. 

Question by jnajmy    |  last reply


L'm trying to sale this pics but i don't know how

Topic by markjr    |  last reply

Design of site?

Hi people. Could you say ma something about site design?

Question by Broneplenka    |  last reply

Is it possible add mA to solar cells in series/parallel circut if you don't use the same number of cells in each circut?

I had in mind 3 circuts running in parallel with one at 4x2v(8v total at peak), and two other circuts running only one cell each, 2v. The mA of each single cell is at 40mA. Would this circut setup make it 120mA? It would be nice to solar power my airsoft rifle's 6xAA 600mAh(3000mAh total) battery pack in less than 30 hours with only a diode in the circut...

Question by ethereal haze    |  last reply

best way to drive 100 leds? Answered

I was gonna wire them all in paralel so it would use 2,000 ma. run it of a 3 v battery with resistors of course the leds need 1.9 v  @ 20 ma any way the wiring could be easier or how would it be easier to drive all those leds to 

Question by ismael01    |  last reply

how do i connect 2 sets of leds that have different volts and mA's?

Ok one set reads current: 20mA suppply: 3.2V and the other reads current: 25mA supply: 3.3V

Question by guy86    |  last reply

I need a diy solution to boost 6V DC to 12V DC @850 mA

I have torroids from pc power supply units, loads of transistors, 555s, uControllers, diodes, caps... all sorts of stuff.

Question by yaly    |  last reply

Artisan's Asylum - craft classes & workshop (hackerspace, maker space, etc.) in Somerville, MA

I'm working with a fantastic group of Boston-area people to get a community craft workshop/maker space/hackerspace,called Artisan's Asylum, up and running in Somerville, MA. We have a small space where we will be teaching classes requiring quiet and clean space, and a big - 9,000 s.f.! - space we are working hard to get set up as workshop/studio (and use for noisy/messy classes). Our goal is to offer tools and instruction in as many craft areas as we can. We already have equipment for sewing, welding, wood working, metal working (we have an awesome CNC mill!), and electronics. Our first set of classes is scheduled and will be starting July 5. You can read the whole list here. A few of the subjects are: Building Art Bikes MIG Welding Introduction to Knitting Introduction to Sewing Clothing Modification Introduction to Robotics Learning by Building the Asylum Arduino for Beginners Advanced Photography We have a long list of instructors interested in teaching different topics in the future, and as our big space gets built out, we will be able to offer EVEN MORE classes at a time. AND BUILD ENORMOUS ROBOTS. Or, you know, small ones. To learn more, you can check out our website, subscribe to our lovely and classic - and low volume - announcements mailing list, or check us out on Facebook. If you have questions, you can leave a note here or email me at jfeathersmith at featherforge dot com.

Topic by jfeathersmith  

Regulated pwr supply using one pwr source to supply 3 lasers w/ diff amounts of V and adjstable mA (info in Details)?

I am working on a multicolored laser unit combining 3 different colored lasers (violet, red, and green) and i would like it so that they can all be supplied with power from one source (such as a AC-DC wall transformer). But each one runs at a different amount of mA's and Volts. I cannot figure out how to get the exact voltages and mA's that i need to run each laser from one power source. here is what the circuit needs to do: --- Use one power source to simultaneously supply 3 lasers with constant voltage and adjustable (using a POT) current. --- Be able to continue to supply constant voltage and current to the other lasers if one is turned off (i dont want the mA or volts to suddenly rise and blow one laser if i turn the other off). --- Use 3 seperate POTs be able to individually adjust the mA delivered to each laser (all of them will run at max mA and if i want to turn down the green i would up the resistance of one of the POT's to reduce the mA flow to the green laser) the 3 lasers that i will be running each have different power specs. below is the max power that i will want to run each laser at. the voltage delivered to each laser this circuit must always remain CONSTANT. the mA's delivered to each laser must be able to be LOWERED from the below specs using a potentiometer or variable resistor. 6V 120mA 4.5V 420mA 3V 340mA If anyone could figure out a circuit or design that delivered these 3 voltages and the same or similar ampages to the lasers from lets say a 12v 1amp power source (it could be more or less as long as i can buy it online), i would be eternally gratefull. i could allways change the resistor and POT values to make the mA's match what i need exactly. I have been looking for somebody to help me out with this and i can find absolutely nobody who knows how to do this. thanks for the time. -Jakob

Question by pianoman2011    |  last reply

How do i determine mA for any given schematic in a book or websitewith parts and voltage only.? Answered

AS a home hobbiest only I have a problem determineing appropiate amps for any given schematic. I dont have a problem with construction just determining propper amps so to be sure of success. tanks

Question by kbyrne    |  last reply

How much electricity is dangerous?

I found plans to make a device to give yourself a static charge using a negative ion generator. It outputs 7.5 kV and 10 mA. I've seen it in use and I know it's not dangerous. I wanted to build two of them together making it output 15 kV. Unfortunately that would also make it 20 mA. I'm not sure what the resistance of the human body is so I guess my question is will 15 kV and 20 mA flowing through a person be dangerous? Thank you for the replies and I'm sorry if this is a stupid question. I'm pretty new to my electronic hobbies.

Question by bruechel87    |  last reply

3W LED Driver

I Want to design a 3W led driver with 9V dc and 350 mA ouput.

Topic by gaurravi11    |  last reply

Cell phone battery....? Answered

Can you charge a cell phone battery with one 200 mA?  Thanks! patti

Question by mckywer    |  last reply

3W LED driver?

3W LEd driver with 9V dc and 350 mA output runs on ac mains supply.

Question by gaurravi11    |  last reply

Will a USB Mp3 player charge with 5v and 88MA? Answered

Will a USB device Mp3 (usually 5v and 100-400 mA) player charge with 5v and 88MA? Will it take longer to charge? Or will it overload the charger and break something? Will a fluctuating amperage, always below the device's requirements, damage the device's LiPo battery?Thank you! I'm going to make something cool!

Question by nepheron    |  last reply

what type of relay/transistor should I use for a 9v 9 mA piezo transducer??

I need to know asap for school!!

Question by SdaMaster    |  last reply

Could a 1500-2000 mA draw from a car battery (in a car) for 14 hours be a problem? Answered

I want to be able to play my portable PS2 on the ride to Colorado in February. It's a fourteen hour drive. I would probably play much of the way up. It will draw 1.5-2 amps. Will this be a problem? Will it cause problems for the battery? Can it handle that for 10 or so hours, with stops in between? Oh yeah, duh! It will draw the full twelve volts. I think the PS2 uses 8.5, but 12v comes out, so... Help?

Question by snowpenguin    |  last reply

How do I to put an mA meter and V meter to my 12v 1.7A regulated power supply with loads that start at 1mA up to 15mA?

I have aregulated power supply 120VAC to 12VDC & 1.7A to operate small coreless motors that start rotating at 1-3mA operating up to 13mA and need to add a mAmeter, trim pot, rheostat and fuse. How?

Question by SirDeClare    |  last reply

A 3.2-3.6 green forward voltage LED , uses 2 ma. to operate? What amperage can it safely handle?

I would like to use one as a charge indicator for a 2500ma. rechargeable AA battery connected to a 2v., 600ma. (full sun) solar panel.2v. solar + 1.2v charged AA battery = 3.2+ v. and should turn the LED on, but can it handle the amps. or does it need a resister in the curcuit to protect it?

Question by heyfeaver    |  last reply

How do i make these leds dance to music? Answered

I want to hook the three led's i have up to my PC sound jack, i have parts, i may need more, but my question is how do i hook them up? please leave comments and or diagrams thank you What I have (for now) 3 Leds: 1 WATT ULTRA BRIGHT LED GREEN 45/ 73 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA 1 WATT ULTRA BRIGHT LED BLUE 19/ 31 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA 1 WATT ULTRA BRIGHT LED RED 34/ 55 Lumens @ 350/ 700 mA 100 degree viewing angle Maximum forward voltage: 4 Vdc Maximum forward current: 350/ 700 mA   TIP31 80V TO-220 Transistor (is this the correct one?) i have 3 i also have 24g hook up wire, 3.5 splitter, 3.5 cable with plugs, many battery options as well as wall adapters OK do i have what i need, do i need resistors, what ohm rating, and watt rating, what volt source?  i dont need it to be portable, will be on desk, a wall power supply would be best, please try to make me a diagram with parts i have, but if more are needed i have plenty of resistors to choose from Ty. and a store right down road :)

Question by dougiedougworld    |  last reply