# Search for Help with voltages in Topics

### Voltage help

Hello I am new to electronics I am having trouble designing a circuit that lowers VDC as ground resistance increases and raises as ground decreases every circuit I've built works backwards. I am working with 5vdc any help would be much appreciated thanks

Topic by Ed69    |  last reply

I recently purchased 10 led's from superbrightleds.com but I cant seem to figure out their voltage. I am not good with electrical terms (I am a noob with electronics) so the led's detail page just confuses me. If anyone could figur out the voltage of them by going to this page here it would be a lot of help. Thanks!

Question by DBMods    |  last reply

### Help with Voltage Regulator

Hi, I have put one of these together for an ATX power supply and have come across something that I might be getting wrong.... In mocking up the LM317 circuit in breadboard (standar one found everywhere on line and on the LM317 pages), I have got the thing metering -11v to +11v??? I am using one of the black ground wires of the PSU on the black side of the volt meter, but cant figure out why I am not just getting positive voltages??? Could the diode be faulty? Or is this in fact correct? Any help appreciated...

Topic by lone_viper    |  last reply

### Help with voltage/resistor

Hello.  I bought some Christmas LED replacement bulbs but they have no specs with them.  I decided to wire one up.   I figured I would go with 1 . 5 volts at 7 1/2 mA.   Using a 9 volt battery, I have a 1K ohm resistor.   9 - 1.5 = 7/ .0075.  My problem is, when I put my meter on it, the one side of the resistor is showing 9 volts, correct, but the other side is showing 3.5 volts.   Shouldn't it only be reading 1.5 volts?  What is wrong?  *I've had the LED lit up for over 25 minutes so far and it hasnt burned out yet. Thank You. EDIT:   I just added  a 10K resistor, so now I have 11K (in series), yet I am still getting a reading of 3.5 volts.   I'm missing something here. lol   I'm also getting a reading of about 9mA with 1K and 11K ohms.   I'm lost.

Topic by pennsteve    |  last reply

### Help

I built a 30kv static electricity generator with nighthawkinlight’s instructable.But everytime I use the switch I get shocked.My 20kv generator doesn’t do it though.The switch i am using also doubles as the battery holder.Can you guys help me find out what i can do to stop it?It is the “Elpa battery case”.It looks kinda like the case above.

Question by HVZapp    |  last reply

### Measuring LED Voltage

Greetings... I have quite a few "salvaged" LED's, none of which have I the slightest clue as to their voltage. I have attempted to measure them using the diode setting on my voltmeter with dubious/mixed/questionable results. Although the measurements are momentary (the reading is barely of sufficient length to note), I can usually arrive at a value. Unfortunately, when I repeat the measurement on the same LED the reading is invariably different. For example, I just measured the value of a random LED (green) and came up with the following: 1.3. 1.4, 1.8, 1.6. I've rounded the values to the nearest decimal point. Are these values through voltage? Are the differences between the readings significant or should I use the minimum when calculating resistor values? I'll, no doubt, have a few more question later on. I appreciate your elucidation on this matter... Best to all, hassi

Topic by hassi    |  last reply

### Voltage for NiChrome?

Will 2.5 volts be enough to heat a small segment of NiChrome wire up to/over 100 C? If it helps, the power is coming from a 8.1 kJ 2.5v 2600 F super capacitor which can unload very quickly.

Question by LiquidLightning    |  last reply

### Led voltages

I have a small pile of salvaged LEDs from various burned up electronics (flashlights, old stereos, etc) and I am wondering if there is any way to figure out what the voltage requirements are for the led. if anyone has an idea how to find this out it would be of great help.

Topic by danlab    |  last reply

### small motor voltage help

Ok i bought this 18,000 rpm motor at radioshack and i want to put it in my airsoft gun (replacing the old one) hoping it would be much faster. But i have have it 6 volts and it is slower then my old motor then i tried hooking a nine-volt to it and it does nothing. I looked on the box and it says 1.93A. what voltage is tht???

Topic by fretmelter    |  last reply

### LED driver and voltage help?

Here goes nothing. How everyone can help. Right now i have a 50watt led that can be wired 85-277VAC. It has a led driver that  has all this on it. Vin:85-277VAC Lin:ac0.35A Vout:DC20-36V Lout:1500MA+-3%MA 50Wa/70Wb Now with all that being said it is an hP0050 led driver. Now on 120VAC it pulls .42 amps. Now at 12V this should pull 4.2 amps. What i need to know how to do is use 12-24VDC input and still be able to power the 50 watt led in DC voltage. Anyone help.. I would need to be able to do it cheaply bc my larger lights ahve 4 of the 50 watt leds in it so i would ahve to do this 4 times..

Question by joshuawcolvey    |  last reply

i have a rechargeable battery that is 7.2 volts and 3000 mAh Ni-Mh now is it safe to add a Voltage Regulator to run an led or if not how do i? what also is scaring me is the 3000 mAh if its good or bad

Question by MACKattacksnipe    |  last reply

### LED indicator

How should I drive an LED from a 38 volts power supply? The led wizard says I need a 1800 ohm, 2 watt resistor, but it also says' it'll disipate excessive heat. I recently took apart a surge protector and found that they drive an LED from a 120volt source by having a diode, LED and what appears to be either a 1 or 2 watt resistor. I need help driving an LED from a 38 volts power supply just as an indicator.

Topic by guyfrom7up    |  last reply

### Project Help

Hey everyone I was hoping someone could help me with a project that I'm working on. I'm relatively inexperienced with electronics so this might just be a simple solution, but here it goes. I have a 4.8V, .9A power source and I would like to connect the power source, a toggle switch, a LED, and a USB port in series. A pretty simple idea. I don't know too much about LEDs, but I do know that you have to use a resistor with it. And I've heard that the LED and resistor have to have a voltage drop equal to the voltage of the power source. My main question is this though: how can I use the LED along with the USB port? Will there be enough voltage left for the USB after the LED is lit? Thanks for any advice!

Topic by msh21    |  last reply

### Voltage Regulator

EDIT: Anyone Interested please check below posts, this is one is obsoleteHello!I need a voltage smoother and regulator on my circuit(attached below)it is a modified shunt charge controller circuit.It converts the Tri phase alternating current to DC and feeds it into the circuit.The regulator will have to be attachable to the BATTERIES wire in the circuit.It should not consume more than 1v power on its own.My Vout to the battery currently is fluctuating.I will need the to be a stable 12v to charge the batteries. A potentiometer will have to adjust current.I will calibrate current according to my battery bank needs.Led 1 indicates 'charging' Led 2 indicates 'Dump'And Please forgive my circuit diagram design(it looks like crap)but works like gold.Also do NOT suggest huge changes to my controller for the regulator to work. Small suggestions to make it more effective,useful like change the zener diode power rating will be welcome.P.S- Its for my hydro project.Check it out at https://www.instructables.com/community/Help-Hydro-power/Kabir

Topic by mhkabir    |  last reply

### Help with LEDs

Hi, I'm new to the whole electronics thing, and i decided to try and make a sign for my brother for christmas. I was planning to back light it with 4 rows of 3 leds in each row, each row being a different color. I was planning to power it with a plug in the wall power supply that outputs 9v DC 450 mA. Also i was planning to have a switch for each row, and a potentiometer to control all the leds. The leds have about a 2.8 forward voltage @ 20mA. I was wondering if it would be possible to power the leds with this power supply, and if so, what the circuit diagram would look like with all the resistors, leds, etc.. (whatever else i need). Thanks

Topic by OpenSpace    |  last reply

### Circuit Help Needed

Hello, i need help with a project for school due in 3 months. And i  need help with a circuit with some odd requests.  A variable resistor will change the voltage from 1-18v.   From voltages 1-10v will heat up a peltier tile  and from voltages 11-18v will change polarity around causing the peltier tile to then cool down but at a faster rate. This all needs to be done without a switch and only with the  variable voltage.  If 1-18v is not possible 1-12v may be even better.    So voltages 1-10v will heat up a peltier tile and from voltages 11-12v will change polarity around causing the peltier tile to then cool down but at a faster rate. And again without a switch and only with the variable voltage.  Thanks! -Jon-

Topic by MRCmegarallycar    |  last reply

### led help????

Ok im a noob when it comes to leds and electricity, but i was told someone heremight could help with my delima. what im trying to do: drill holes into tail light on my ninja and put yellow leds in the hole and wire them to the existing blinker wires. the problem: messured the voltage coming off of the wire and it pulses from 0vdc to 7.22 vdc i have been looking on ebay at prewired 12v leds but dont know what im needing. any help wouldbe greatly appreciated!!!!!!!

Question by pierce-custom-bikeworks    |  last reply

### How to make Voltage regulators

I would like to know how to make a voltage regulator for an old generator. The regulator has stopped working and is hard to replace. I need an out´put of 120 volts with 15000 watts and ofcourse the 50-60 hertz. Thanx for your time

Question by Soochi    |  last reply

### Help me!!

Https://www.instructables.com/id/plugduino-Arduino-based-120-Volt-outlet-controll/ In this Control circuit schematic They explained about sensor inputs (the sensor inputs are connected to the analog inputs on the Arduino board ( A0, A1, A2, A3 ). The input voltages on these pins are converted into a 10 bit integer value such that the range between 0V and 5V and translated into a value between 0 and 1023 respectively. The ideal connector thus contains 3 inputs per sensor ( 5V, GND, A ) resulting in 12 connection points.) I need clear explanation about this and what type of sensors they using and how they connected ?? Thanks For ur help :) :)

Topic by svenkatesh3    |  last reply

### Traffic signal input voltage help

I have recently bought this traffic arrow from a surplus store and i cannot find the input voltage anywhere on the net. it has a built in switch mode power supply from what i can tell and i think it is 120V AC but am not sure. the arrow is a GE Gelcore LED Traffic Signal. ANY help would be appreciated.  thanks

Topic by devicemodder

### High voltage discharge capacitor help?

I recently got a 50uf 2000 volt polarized pulse discharge capacitor to blow stuff up. I tried to charge it with a microwave transformer rectified by a single HV diode, but that did not work. My plan was to fire up the microwave transformer, close HV switch #1 to charge the cap, open HV switch #1, and turn off the microwave transformer. Then I would close HV switch #2, and would send power to "load", in this case an orange (see diagram). However, when I closed HV switch #1 (which is a nail in a piece of wood and a rod on a PVC pipe), I would get arcs. Then, when I closed HV switch #2, nothing happened. I even tried shorting the cap with a rod, but it had not charged. Before this test, I tested the capacitor by charging it to 120 volts and it worked fine (I got a spark). Also, there is no internal resistor to discarge the capacitor after a long period of time. Should I try a full bridge rectifier with 4 diodes instead of a single diode? I will also include a schematic of the circuit (you might have to zoom in in order to see it).

Question by TimTD    |  last reply

### Help with Resistance formula. Answered

How to find the voltage after adding a resistor with the resistance formula? For example I have a circuit that uses 0.975A and I add a 1000ohm resistor to it, if its powered by 220v main then according to V=IR what should be the voltage drop due to the resistor?

### AVR Help

I finally have all I need to start programming, I have a programmer (this one to be exact)http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd;=1&item;=130202441672&ssPageName;=STRK:MEWN:IT&ih;=003and I have a bunch of attiny13vYou can talk to me as if I know nothing about microcontrollers and programming.I have googled for about 10 minutes and havn't found a tutorial or anything that can help me. I just want to learn the most up to date stuff, like I don't want to learn assembly if I can use C (I don't know C). Please, I need help.Also I need help of how to setup everything on a breadboard, like what pin of the 10 pins from the programmer go to which pins of my attiny13 and where to apply how much voltage.

Topic by guyfrom7up    |  last reply

### High voltage NOT gate Answered

I am creating a circuit and I need a not gate to run 20 3v 20mA LEDs. The only problem is that to run all of those LEDs (4 series circuits in parallel, if that will help) I am using 18 volts (2 9v batteries in a series). My circuit is compact (,think fitting inside an Altoids container) so a relay wouldn't work. So I need a high voltage way to make a not gate. I can read schematics if that will help you explain it, but I do need you to mention the ohms of the resistor. Thanks a million!

Question by GenAap    |  last reply

### How to make a voltage multiplier?

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

Question by Kalrag    |  last reply

### What is the best voltage for the IN-12 Nixie tube?

I want to make a desk clock using four IN-12 Nixie tubes. Mostly, 170V or 180V applied to the Nixie tube. I want to know which part of the tube the applied voltage is affecting.And I have found that current affects the lifetime of a Nixie tube, and I want to know if the voltage affects its lifetime.

Question by ho june

### Voltage of iPod Battery

Ah, so I have this iPod Shuffle Gen 2 (which I really dislike, I won it in a contest), and I would like to know what the voltage of the li-ion battery inside is or about is. I don't know if anyone knows, any help would be nice. Thanks!

Topic by Bran    |  last reply

### voltage regulators and supercaps? Answered

I have 12 .22F 5 volt supercapacitors that i bought recently. Ive been thinking about making something like the Mintyboost from Adafruit but am unsure on how to do it with supercaps. Any help is appreciated as this is stumping me pretty well. thanks, bud

Question by budhaztm    |  last reply

### Help with zener diodes? Answered

I'm trying to get a better grasp on how to use a zener diode. I have plenty of information about what they do (allow current to flow one way until the voltage is high enough, then reverse the flow), how they work and even how they are made, but finding basic information about how to use it is harder. I am trying to connect a Keyboard Encoder to an Arduino. The Encoder runs on 3.5v and the Arduino runs on 5v. When a pin on the Encoder is connected to ground it outputs a keystroke to the computer. I have an Arduino pin set to HIGH (5v) as normal and under some conditions it changes briefly to LOW (ground) which is when I want the Encoder to output to the PC, and then back to HIGH (5v) again. To protect the encoder from the higher voltage coming from the Arduino I think I need to use a zener diode. If my understanding is correct it should work as described in the diagram. When the Arduino pin is High (5v) the Encoder reads as 3.5v and any voltage over 3.5v is drained to ground rather than pushing against the Encoder. No keystroke is passed. When the Arduino pin is LOW (0v) the Encoder reads 0v, the zener diode adds resistance and voltage runs to the Arduino. The Encoder sends a keystroke to the PC. My main concern is that once the voltage is over the 3.5v all of the power will drain to ground rather than maintaining the 3.5v before the zenner diode. I can't find anywhere which will tell me either way. If you need more information on my set up please let me know. I'm really struggling to get my head around this! Thanks!

Question by RandomIdeaMan    |  last reply

### Led driver help.

I want to make a aquarium light unit with 100 cool white 14000k 3w ,DC Forward Voltage 3.4-3.6V ,Forward Current 700mA and 100 Royal Blue DC Forward Voltage: 3.6V - 4.0V  ,Forward Current: 700mA  i want 2 dimmers 1 for whites 1 for the blues, can someone please tell me what divers i need  and how many i need. if imposable links to the driver on ebay.

Question by awilloughby3    |  last reply

### Low Voltage Disconnect?

Hi, I would just like to seek your assistance and idea for the observation below on my experiment: I have a gadget that is being charge by a 2w 9v solar panel, the problem is I haven't place a blocking diode and I observed that when I tested the charging slot there is about 0.16v output. To clear it that was supposed to be my input voltage. 1. Question is why does it produce an output voltage even though it is imy input voltage? 2. Would the 0.16volts output have a significant effect on my system during night time and or bad weather? Please give facts and computation if possible. 3. If I want to step down my input voltage of 9volts to 4.5 volts can you give me the idea how to do it. Well, I am asking you this because your insights and helps for me in the past are very helpful for my science project. Thank you teachers

Question by mitchiko    |  last reply

### Led Help

I have a whelen white vertex led light head. Normally there is a 12 volt dc controller already attached to the light it self that controls the flash pattern which you can change. However some one cut the light head off the controller part and the controller cant be found so now i have just a light head with 3 wires red black and green red being power green and black being ground. there are a total of 6 leds 3 off the green wire and 3 off the black and a common power wire. my problem is i cannot figure out the proper voltage and ampures needed to power the lights. i have tried to ohm the leds (and yes i tried every which way with the leads) but i suppose my fluke 115 does not have the range needed for these lights. i connected a known working light and controller to 12 volts and mesured the power going to that light which read which read about 3.7 volts at .36 amps and each set of 3 leds being .18 amps and with out any leds connected i got 5.2 volts i just want to make sure this is correct before i put 5 volts and a resistor to them and they blow. ill post pics and a crappy diagram of what i think is in the light head

Question by Nnhalo360nn

### Compact ight sensor switch with low voltage

Hi there,I've got a led light that's operated via a magnet, if it doesn't detect a magnetic field it turns on if it does it turns off. It's a led light for car door(check picture for reference) and uses 3x AAA batteries in my case 1.2v x3 (3.6v), if you use regular batteries it's 4.5vBy mistake I've order a tiny light sensor module 3.3-5v(check picture) which obviously can't be used as a switch, not in it's present form. While I'm good with solder, I've build an ebike, I'm a computer guy but when it comes to things like this like this make me feel powerless :( ..I 've used 12v light sensor switches but that's a different topic.So, how can I have a low powered light sensor switch that's compact and can save me from replacing the batteries frequent? ...the led light turns on even at daytime which has no point in doing that. I'd appriciate any help :D

Topic by Takisk1    |  last reply

### +Help with Digital PSU+?

Hi everyone after many days of constant tinkering, I finally got the circuit of my Digital Power supply made. However, I am experienced difficulty in the programming side. I am using an Arduino with an LCD (and various other io such as a current sensor, voltage divider, button and rotary encoder). My program is limited to what I could find online for an ammeter/ voltmeter sketch. I wanted help or some guidance in figuring out how to use the rotary encoder to 'set' a voltage (visible on the lcd) and when i press the button, i send a certain signal to my DAC which is connected to my psu circuit. and i wanted to be able to switch over from voltage 'setting' to current 'setting'. Frankly, i have no idea how to do this :s ! here is a video of what i want it to almost look like https://www.youtube.com/watch?v=bGnTzT_OCpc Thanks

Question by making9719    |  last reply

### Circuit Design Help

Trying to build a simple circuit to power a small pump while the sun is out. Here are the specifics: Solar Panel (60 cell mono panel) Open circuit voltage 36.4V DC, Short circuit current 7.96A. Pump 12 V DC, 9A max Using E=IR ,  R=E/I, (36.4-12)/7.96 =  3 ohms Power = V(sq)/R = 24.4/3 =198 watts  I purchased a resistor that meets these requirements and hooked everything in series. (Solar panel lead to resistor, resistor to pump, and pump to other solar panel lead. The pump does not turn on when the panel is in the sunlight. I measure the voltage coming out of the panel and it is within specification. I also tested the pump by hooking it up to a car battery and it works fine. Any ideas what I am doing wrong? thanks!

Topic by OMGIMDUMB    |  last reply

### Need help with this driver? Answered

Hi, I have 3 blue  x 1w high power leds, specs are: Forward voltage: 3.2v - 3.6v Forward current: 350mA Intensity: 70-80Lm Color temp: 6000k to 6500k I have this led driver but want to know if it will drive the 3 led lights at each 320mA or total 320mA divided x 3 Driver specs: LED power supply driver Power: 3 x 1W Input voltage: 80-265V/ 50-60Hz Output: DC2.5-12V/320mA

Question by Lion_Heart    |  last reply

### Camera Taser help!!!

I'm making a taser out of a camera and was wondering when adding more capacitors do they all the to be exactly the same?? same voltage? im going to wire them in parallel..

Question by Emsaid    |  last reply

### Help with charging capacitors

How do I charge my 450v capacitors with a 120v outlet? I am building a rail gun and need to get these up to a high enough voltage.

Topic by gclark0812    |  last reply

### how to run a high voltage motor with low voltage Answered

Hi there, I just wanna know how to run a 12v D.C motor using a 9v battery, is it possible by using  voltage and current doubler circuits? please help me, as i want this knowledge for a project of mine

Question by VivekM12    |  last reply

Hi Guys, Looking a bit into voltage regulators. When I'm looking at the wiring diagrams on the datasheets, most of them indicate that it requires a 30V+ish input voltage to work. I was hoping to get a small adjustable voltage regulator to run off the 12v range. I really don't need anything over 12volts anyway. Can I get this to work or do I have to find a power supply capable of providing 30V+ for the voltage regulator? I was looking at models such as the lm117 if it helps. Also, If I do need 30v+, where can you suggest I get that kind of power supply? I usually use 12v wall adapters. Thanks!

Question by transistorguy    |  last reply

### Increasing DC voltage

I need to increase the voltage of a battery from ~30v to ~230v, the only way i can think of doing this is somehow pulsing the DC rapidly to create a sort of "pseudo AC" then using a standard transformer to increase the voltage, followed by the standard rectification process. My problem is how to pulse the DC (bearing in mind the pulse will probably need to be in the order of kHz, and the device being powered at 230v has a power rating of 400W) and how to after the rectification process implement a pwm system. In addition, the method of increasing the voltage strikes me as extremely inefficient, so if anyone has any other ideas I would be very great full. Thank you for any help you can provide.

Topic by csharpdeveloper    |  last reply

### LED power suppy help?

I am plan to run 4 leds in a seires parallel configuration. The leds have a forward voltage of 5.2 and run at 350 ma. Would it draw more power if I had a higher input voltage or would it still draw the same amout. I am trying to decide between lithium ion batteries and NMh.

Question by jack.h    |  last reply

### AC Voltage Attenuation?

Hello, All- I am making my second version of the "Tube Lamp." Others have managed to wire in these neat-looking old analog meters on theirs, and I thought that would be something I'd like to try. I bought a couple 1-10VAC meters from fairradio.com... The problem is (besides the fact that I am an electronics idiot) that obviously if I try to wire in this particular meter to normal 110 AC, the meter will blow up. Is there a way to attenuate the voltage coming out of the dimmer to "play nice" with the 1-10 VAC meter? I suppose I would need to divide the voltage by a factor of 10. How would I step down the voltage to the meter only, while supplying the bulbs with the proper voltage? Any help would be appreciated!

Topic by 40percentrobot    |  last reply

### circuit troubleshooting help

Hi- First on an unrelated note, does anyone besides me see "A fatal, non-recoverable error has occurred" over on the Makezine forums when you try to sign in? I've been getting that for weeks! Anyway... I'm working on a variable power supply that uses a 317 to regulate the 18 volts coming from a laptop switching supply. There are two 5k 10-turn (for precision) pots with a switch so that you can have two "preset" voltages and switch between the two of them at will. There's a single output. There's also a little lamp (I used a micro mini 12v lamp instead of an LED because that's what I had) that goes on above the pot that's currently switched in. The circuit I built (schematic is below) seems to work more or less fine. 'cept there's two strange issues: First, although the pots are linear (not sure if that would make the difference or not), they seem to "flatten out" toward their upper range. The first six turns gets you from 1.2 to about 16.5 volts. Then the last four turns either don't change anything or they do so in _very_ fine increments so that you only get from 16.5 to just over 17 volts. That's in four whole turns of the knob. This happens for both pots. The second stange thing is that turning the non-activated pot will affect the current voltage. When you increase the resistance (turn the knob to the right), the voltage level actually drops! Conversely, turning it to the left will increase the voltage. Remember, this is the switched-off pot. The switched-on pot works as it should (barring the mentioned weirdnesses). It looks like how much the voltage changes depends on how many turns you've given the activated pot. I suspect this has to do with me using a SPDT switch instead of a DPDT and maybe some voltage / current bleeding through the lamps and into the adjust pin, or something. But I ca/n't figure out why the switched-off pot would do anything. Anyway, take a look at the schematic. Is there anything I've done wrong that I'm missing? Should I, um, switch (*cough*) to a DPDT switch (something like the second schematic)? I used the SPDT cuz that's what I had. Anyy help is appreciated, Thanks!

### Laptop Fan Help!

So i bought a 2.8ghz laptop from a guy for \$30i fixed EVERYTHING, invested about \$200 of my hard-earned moneyand now the CPU fan wants to crap out on me >: ( the fan works, the circuitry that controls the fan has failed (on the mobo)so what i am asking is that you help me!i need to be able to regulate the 12v that comes from the battery into lower voltage, with a variable power supply, https://www.instructables.com/id/How-to-Build-a-Bench-Top-Power-Supply/I need someone to do the calculation so that i can regulate voltage form 4.5v - 12v what would be the resistance values?VOUT = 1.25 * ( 1 + ( R2/R1 ) )

Topic by Sandisk1duo    |  last reply

Hello, i am an electronics hobbyist, and want to develop an system which is an voltage quality recorder, i mean it measures the various voltage disturbances like transients, swells, sags, THD, etc, I was comfortable in analyzing the concept and with the software too. but for the hardware implementation i am confused of which kind of TI microcontroller or microprocessor is suitable for my project. i will work on the real time calculations and will use FFT in analyzing the voltage.I am planning on dsp processors of C2000 series of TI. But not able to wisely choose them. On what major parameters should i look upon while choosing them. I would be helped if anyone can suggest me which one would precisely be used for this cause. Any more suggestions on how to proceed with it are welcomed. Thank you.

Question by Tejas Narayan    |  last reply

### LED Voltage indicator

I have recently installed a solar panel in my garden to charge a 12volt 21Ah battery. I would like to show it off a bit by using a simple LED display to show it working. What I was thinking was to have a range of about 8V-25V. At the low end would be blue leds (for cold) up to red (hot) at the high end. Does anybody have any idea how I would go about getting something together. I can read circuit diagrams at a push (my Dad's the expert) and would like as much information as possible. Would it be possible to have 1 LED per volt ? Am I being simple? Would this project be self defeating in that it'd use lots of the free power I'm trying to collect? Any help anybody can give I'd be grateful to receive. Share & Enjoy. Zippy.

Topic by bunglesmate    |  last reply

### LED Setup Help?

I have 30 led i will like to setup but i am not sure what led driver i need any help would be nice. can i got a led driver with less forward current them my led need? 20 1w led  Forward Voltage: 3.2V~3.6V Forward Current 300-350mA 10 3w led  Forward Voltage: 3.0V - 3.7V Forward Current: 700-750mA Was  thinking  two the below led driver for the 1w led http://www.ebay.com/itm/280840190067?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3492wt_1163 and   One of the below led drive for the 3w  http://www.ebay.com/itm/320936909163?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3672wt_1163

Question by sgon    |  last reply

### i want to double the voltage to 600v in my taser .how can i do that?

I want to double the voltage to 600v in my taser .how can i do that?

Question by ouwelou    |  last reply

### Vacuum pump voltage?

Today I was dumpster diving and i found an old vacuum so i decided to take the pump out but i made the mistake of not checking what voltage the vacuum runs on, because it also had a spinning component at the mouth of the vacuum. I think the pump works fine because i noticed that tube connecting the mouth of the vacuum and the pump was broke. Is there anyway to find out what voltage it runs on? would standard 120 be ok?The markings on it say 81 b-9 ECP 6500-240 HPU+ 60hz HD10 120 vac 07:07 does that mean it will work off a standard 120 outlet?update: What I am going to do with this motor has been decided. I will be attaching it to the back wheel of my bike with a car battery, i will install some type of switch on the handlebar or add something like a dimmer switch, this would allow me to have the motor on if i want, and i can adjust the speed. Please help fine tune this idea.

Topic by astrozombies138    |  last reply