Hey, I need to know how to turn 9v into 3v can anyone help? Thanks, Cory
Topic by Flumesoft | last reply
Hey everybody. First, take a look at this question's best answer - https://www.instructables.com/answers/How-can-I-make-a-9-volt-shocker/ It tells you how to make a 9v shocker out of a CRT monitor's flyback transformer. I really like the idea and I just have an extra monitor at my friend's house, so I thought about trying it. I saw some videos of people messing around with flyback transformers, and it really looks dangerous. If I follow the guide on the link, and get the shocker to work, will it be dangerous? I'm gonna use it for pranks and self defense(I'm a HUGE fan of knives and I know how to use them, but they're illegal to carry here and can cause serious injury), will it be ok? Thanks a lot, Mike.
Question by netbus | last reply
I'm working on an LED IR Illumination circuit (KipKay's nightvision with just the LED circuit). The thing works great but kills my 9v batteries pretty quick. I have a 9.6Vdc 300ma power adapter. Is is possible and SAFE to use this in the circuit instead of a 9v battery? Sources: KipKay's Project https://www.instructables.com/id/Super-Nightvision-Headset-Hack/ Power Adapter http://www.noiseguide.com/product_info/h_pro_96vdc300ma_adapter_ps200r120
Question by mrgrim333 | last reply
Hi all. I am new to this forum and need some help. I want to mount an led strip to the bottom of a roller skate. Everything I find already made up requires 12v. I need to keep the setup as small as possible for mounting reasons. How could I go about making a 12vdc led circuit work off a 9v battery or how could I wire up some led's on a flexible strip powered by a battery. I am thinking 9v because I can purchase a rechargeable set without draining the bank account each time. Any suggestions are welcomed. I have about 6" in length to mount the strip to. I would like multi color led but one solid color would also be fine. Thanks again for any suggestions.
Topic by rsfaze | last reply
I want to use a lab power supply to run simple ohm's law experiments instead of using a 9v alkaline battery. One of the experiments uses a resister in series with an LED to show the effects of how a resister limits current. I can set my lab power supply to 9V but I don't know what current to set it to in order to be the equivalent of the 9V battery. Can anybody enlighten me please? I'm just getting into learning electronics.
Question by woodyd | last reply
Alrighty, sorry for the noob question, but i am very very new to this, i'm tryin hook 3 10mm LEDs to run off a 9v battery, i hooked it via the LEDcalc with correct resistors, it works just fine, but when i try to add a on/off switch into the mix the 9V gets very very hot. could it be ... the switch i am using... the 24 gauge wire to connect it all.... how i have connected the on/off switch into the mix , instead of connecting it straight to a battery i have added extra wires and put the switch in between the battery and the start/end of the LED chain... should i bump it down 6v instead with the correct resistors instead of the 9v also if you could explain why the 9v was heating up so much that would be great too....
Topic by pixelglasses | last reply
I want to limit two 9V battieries, in serial to 12v. I want to run a cold cathode off em, if the strain is too much, I'll join two parralell sets of two 9v batteries in the circuit. Anyway, how do I do it? I can't find any 12V regulators at all, and I don't know what sort of resistor I'd need, is there one that would limit it to 12V, with the standard 9V battery ampage? How could I archive this? Thanks.
Topic by Josho | last reply
Does anyone know how to convert 9vdc power to 12v dc power? ive looked all over the internet and nobody seems to have any schematics for anything like it. It needs to be about one or two square inches. Its for a pellet rifle with a built in air compressor so i can travel through the woods and not have to worry about going back to the truck and airing it up. please email me at email@example.com thanks
Question by mongoose_08
The adapter says it runs on 8.5 v
I'm looking at powering my Arduino with 2 9V batteries wired in parallel (2 is optional, but if you think a single 9V battery can power an arduino + 16 LEDs simultaneously for >3 hours, let me know). I have a few different options for linear regulators. LM350 (3A), C33275 (300mA), LM7805 (1A, 5V) - I'm guessing I should use the LM7805 because it's fixed at 5 but I'm not sure. I'm not too electronics-savvy so as much help as you're patient enough to give would really be appreciated!
Question by jonrb | last reply
My friend has this thing that looks like a pack of gum and when you grab and pull the piece sticking out it shocks you, it isn't really that powerful, but I want to make a better one. I opened it up and it is a fairly simple device. It has three button cell batteries with the negative side attached to a contact plate and the positive attached to the capacitor. The capacitor has the neg attached to the same plate as the batteries negative. The only problem is that the positive plate is attached to a third prong on the capacitor. Why would a capacitor have three? I have tried charging a 220 uf cap. with a 9v battery, but it doesn't deliver any shock even though it should be higher voltage and capacitance than the original device.
Question by jj.inc | last reply
Problem: I have a 16f627/628 (runs between 3 and 5 volts) that needs to work in tandem with another device (call it D) running at 9, direct current, (active for 1 second in 30 or less frequent). Upon hooking up a number (of descending in size) resistors (without D connected) with the supply and 16f6xx the 6 LED's powered by the 16f6xx do not turn on unless resistance is extremely minimal, and voltage is well above that advised in the datasheet (not to mention making the pic reset itself every 10ms). Can anyone tell me how I might run the 16f6xx from a 9 volt battery, and explain what was going on? This may seem unforgivably dim to anyone who knows but unfortunately I'm more a software guy learning hardware as I go along. Any help would be much appreciated, Thanks Andy
Topic by andy | last reply
Circuit boardim trying to create a circuit board with leds on it that spells out my handle. i was thinking of using it as a throwie or like a calling card. im totally new to this so i didnt want to try and use a printed circuit board since i have never done anything like this before. i used a circuit board i bought at radio shack. im building it with standard super bright 5mm leds that are about 2.1 v and im not sure how many Ma. i assume 25 Ma. no matter how i plug these numbers into my formula (source volts - led volts / Ma) the leds always seem to run hot. i cant figure out what resistor to use. the power supply is a 9v battery. i also would like to know how to string about 30 of them together off one 9v. i know its alot but can anyone give me some advice or help me out?
Topic by mat_massacre | last reply
Hi I am trying to make a display of my polymer clay angry birds in our local fair and I wanted to add a few little leds on it, the problem is they need to stay on constantly for at least 5 days I am trying to figure out how long a 9v battery would power about 6-8 leds. is there a better way to do it? ~Thanks
Question by AsherB4 | last reply
The fan is for the combustion chamber of a spud gun and comes with an internal toggle switch but I would like to use the external lighted switch. Suggestions are appreciated, Thanks
Question by JackH19 | last reply
I need to build a voltage multiplier for 9v to about 4kv
Question by tulavatalo | last reply
I have a Philips CD250DUO cordless phone that has no user's guide , and a GE Atlinks cordless phone that is powered by 9v i50mA i wonder if i could use my 9v 300mA adapter on the Philips brand and can anybody tell me if there is free download of user's guide for this device
Question by jovenhatsjr | last reply
Question by Slicerr2 | last reply
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
Topic by TheAtomicSoul | last reply
I am using a rechargeable 9v battery in my irrigation timers. I would think it would be easy to hook up a small solar panel to charge the batteries during the day and then I don't have to worry about them failing and me not noticing until my garden goes brown. Two wires join in a pastic coated cap that hooks to the 9volts. Can't I just take the cap apart and connect the leads from the little solar panel?
Question by solartimer | last reply
Some say the resistor gets attached from the positive battery lead to the first led. Others say that the resistor is attached to the neg pole of last led and the ground wire of the battery. What the Hey?
Question by ClandestineIntestine | last reply
Hello i am writing up an instructable on setting up a wireless receiver , however i requires both 5v and 9v output, and the whole point of it is that it is simple and cheap, so i need to know, how many ohm resistor do i need to step down 9v down to 5v? i do not wish to use a 5v regulator unless one can be bought for less than $2, or else the instructable will cost too much.
Question by oldmanbeefjerky | last reply
I'm trying to light up the dash in my truck and everything is ready except im plugging it in to the 12v DC cigarette lighter and I know it will blow them all sky high but I already tested and 9v DC is what I need. Thanks in advance!!!
Question by TamaMan14 | last reply
I have an 8th grade science class (I'm the teacher) that I would like to have construct underwater vehicles. The kids will be using 9v batteries, switches and assorted other materials. Does anyone know of any good books/articles that explain the basics of wiring, electricity, motors, switches, etc. that I can have the students read to get a good base of knowledge in the basics of electronics? Thanks!!!
Topic by mashmtz | last reply
Hi, I'm building a mini BB-8 unit for a project and going to make many more for a club. My biggest problem I'm encountering now is the battery needed to power it. The entire circuit draws around 500mAh and runs on 3-5V. I don't think a 9V battery is enough to power it or even a AA battery no matter how many i put on it. The online guides that I found uses 18650 batteries either salvaged or bought. However, from where I come its very expensive to buy this batteries and it the charger cost even more. So I was thinking of buying this cheap 2400mAh powerbank that is sold commonly here. It outputs 5 volts and can be charged by USB. This powerbank cost about the same price of a 9V battery but only have life span of about 2 months which is good enough in my opinion. My main question is are there any other alternatives to power this circuit at a cheap price and is it possible to use a powerbank to power this circuit? Tq for any help and suggestions.
Topic by KhayhenS
Hi there! I'm planning a project using a 12vdc case fan to inflate a plastic bag for a school project. I have located a 9v battery clip and a 2xAA battery holder and was wondering how i'd go on with wiring them together. I was also wondering if it was possible to reverse the polarity, thus creating a vacuum effect. If so i'd like to have a 3 prong switch to control the case fan. I appreciate any help you could provide me. Thanks!
Question by williamhaze | last reply
I had an idea for a project where I will (literally) Set Fire To The Rain. So I need a spark gap. Anyone know how to do this? I think it would be easy to charge, then discharge a flash capacitor. If that's a good plan, where can I find a schematic for a charging circuit?
Question by 4lifenerdfighter | last reply
I have bought a turntable which comes with a USA transformer 9v 400ma. I want to use it in Sweden so I have to buy a European transformer. I found one that transform to 9v 1000ma. Is it going to cause any damage to the device if I use it? Thanks.
Question by terristel | last reply
I have a Roland D2 Groovebox that I'd like to use portably. It uses a 9V 1000ma AC adapter that I've misplaced. I prefer battery powered stuff so figured I'd take this as an opportunity to try to make it so. I'm comfortable with some soldering and cable splicing, but definitely lack the electrical knowhow to even know what questions to ask. I'm interested in either buying a battery housing for disposable battery power (AA thru D cell) or making a wire that can plug this into a rechargeable power bank. I assume this may be an existing product but, again, I don't know how to search for it (and, again, would also be happy to whip one up).
Question by ThomL9
Question by Yashknowsbetter | last reply
I just recently got a free laptop from a friend who's dad didn't need anymore, and it dosn't have a power cord to charge the battery. I'm dieing to turn it on and see if it works so if anyone knows who to convert a 9v dc adapter to 18.5 if it's even possible.
Topic by CowGuy | last reply
I want to run a motor attached to a motion sensor in such a manner that the motion sensor triggers the motor. The motor is run by 6 1.5v D cell batteries, thus I imagine requires a 9v draw. The battery operated motion sensor also requires 9v. If I wire them in series, which I (hopefully correctly) understand would require 18v total and thus would require some number of batteries wired in series to achieve that total. Correct?
Well, if you have seen the altoids solar battery charger, and the altoids 9v usb charger, then you must have thought, "why not put em together???". Now, Im not electronics buff, but I'd be willing to bet that since the 9v charger instructable is so small, that it could be incorperated with the solar panel kit. Now, my question is, would i have to do anything ridiculous to convert the solar charger (which is ment to charge 2 AA batterys) into a 9v usb charger w/solar panel while still being inside an altoids tin. PS: I still don't know why I have this wierd fascination with altoids tin DIYs, but I do...
Topic by altoidsrox
Hi everyone! i am planning to use 2 servo motor and a LCD, all connected to my arduino. but of course, the 5v from the arduino aren't enough to power up everything. so my question is; can i use an external source (9v battery) to power up the motors? if yes, how? appreciate the help. thanks.
Question by nurazureen | last reply
Hello! Im working on a Staples Button Hack! but..... Problem that I have is that I feel like it is a Waste to scrap the original "that was easy" message. And the problem that comes along with this would be that I have to use a 9v battery to power the new circuit and the original button circuit uses a 3v battery. I'm not great with Ohms law but I do relize that I need a resistor but... i do not know if that will put in too much current into the original circuit?Would anyone know how I can calculate this? And does the amount of current even matter? -Thanks! Noobiefied
Question by noobiefied | last reply
If you are interested in what i am doing with my wii check it out ( http://www.wiinode.com/forums/index.php?showtopic=4280 ?... ) As you can see with my site i have a screen that uses 9v and i need it to be used along with the wii (so i only have to carry around ONE plug in) i have my amp wired to my wii using 5v and it works great. I need my screen to work alongside my wii. Ive tryed a 9volt battery before but some reason i get a blank screen but my ps1 7v power connector makes it light up good.when i plug 5v on the screen it leaves it very dim. There is 12v also there are alot of 5v points and some 3.3v points on the wii, could i combine them in some way to recieve my needed voltage or use the 12v? anything thats not to costly or spacey (need my smallage so i can have a small case) and please dont post about me NOT needed to do this thank you. if you need more info say so and ill update the question. I KNOW THE RISK INVOLED WITH WHAT IM DOING!please also note that pics are old. Just giving them for info purposes. Please ask me if you need any other details. :) thank youEDIT: fixed the link.
Topic by Wiimote Master | last reply
I was wondering how many amps would these two LED bars need in order to work if connected in series, and would a regular 9V battery be enough to power them ? http://www.dx.com/p/high-power-3w-7000k-200lm-white-led-puri-chip-emitter-metal-strip-12-14v-65783#.VgrNC9RXeK1 What kind of battery should i use if a 9v isnt enough ?
Question by TarikS5 | last reply
I am working on a costume that utilizes shape memory metal. I plan to use a 9v to briefly heat the metal to its transformation point of roughly 115F where it springs to shape but I would like to prevent any possibility of this momentary short circuit from blowing out the battery. I have yet to fully grasp the applications of diodes, transistors and resistors. is there any kind of simple setup someone may suggest? I've also considered the use of microcontrollers or relays but im trying to keep as simple as I can.
Question by SideTracked350 | last reply
I plan on wiring 8 IR LEDs in series with a 9v battery to power them. i pulled the LEDs out of some remote controlled helicopters so I'm not sure of the values. if there's a safe way to go, what resistor/s should i use?
Question by tokymaru | last reply
Hello guys, I'm pretty new to LED work and this might seem like a really round about process to how I did this but I'm going to explain the whole thing and hopefully find a solution to my problem! First off I bought these Fairy Lights: https://www.amazon.com/gp/product/B01MD1RQ6Q/ref=oh_aui_detailpage_o01_s01?ie=UTF8&psc;=1 I bought them to put into rave fluffies (that I hope to sell at some point) I've attached photos below of what they look like if people didn't know. I bought them because of the small battery pack so they could sit nicely along the legs and not bother anyone and, because they're rainbow and do a beautiful blinking pattern. The problem with them is that the battery packs completely sucked. Big time. They would work for about a minute and then start loosing higher voltage colors and then about at the 3 minute mark they would just be totally red. I figured they were crappy batter packs so I decided to mess with it. Rave Fluffies: http://ep.yimg.com/ay/yhst-11088499841243/striped-fluffies-monster-blue-pink-purple-white-24.jpg The fairy lights themselves were to short so, I decided to solder to strands together, then I trashed the battery pack that came with them and replaced it with a 9v batter pack adapter. I tested it out on some 9 volt batteries laying around the house and it looked magical. All of the colors stayed much longer and it was beautiful! So, today I went out and bought some new batteries they're Energizer Max 9V. I put the fluffies on and put them in and I wanted to test how long they would last. By about 5 minutes I felt a burning against my leg where the battery was. I took the fluffies off fast and discounted the battery. It was extremely hot. Almost to hot to touch and it left two nice low key red burns on my legs. I don't understand what caused this when the other batteries were fine? I also used a 9V energizer battery before. But, the only difference is I'm not sure how much power was left in it while these were fully powered! I hoping to find a solution to this and hopefully it's an easy fix! Also, Bonus points to whoever can send me in the right direction to buy fairy lights like these. Rainbow, blinking, with a small battery pack that doesn't poop out on me fast. I would prefer not to do this much work or something I intend to sell but, if that's what has to happen it's not the end of the world. Thank you so much!! Much love, Meisha
Question by MeganB126 | last reply