I need to make an electromagnet that continues to turn on and off (on 20 seconds off 45 seconds)

Hello, I am trying to make an electromagnet that turns on and off on an interval. On for 20 seconds off for 45 second. It would continue to turn on and off until the power is turned off. Any and all suggestions as to how to make (or buy) this would be great! I am making this for an art piece.. I am a glass artist so I am not well versed in any of this electrical engineering Thanks! Maia

Posted by MaiaS5 6 months ago


Optical Image Stabilization

Hi everyone, I have a little awkward question here but I am sure someone who knows a little bit more about electronics can give me good advice. I took apart the lens from a consumer video camera and took out the Optical Image Stabilization module in an effort to figure out how it works and possibly hijack the signal so I can control the movement. In the camera this module is getting the signal from the accelerometer so it knows how to engage the two electromagnets and counteract the movement (shaking). What I have done is take the leads that go into it and try to fake what gyro sends to this element. So far I have noticed that when I short 1 and 2 or 3 and 4 the element goes to one side or up. So I put a potentiometer on it (2K ohm) and it gives me some control by turning the dial, but not good enough. Has anyone any idea how can I achieve a gradual movement of this lens element vertically and sideways with a slider or dial of some sort? Your help would be greatly appreciated!

Posted by Sudija 10 years ago


Electromagnet Trouble

I'm in the development stages for my entry into the Launch It contest. Right now I'm just experimenting (or trying to) with scale electromagnets. I'm using solid core insulated copper wire from RadioShack, and a nearly fresh 9v battery. I tightly wound the wire around a finishing nail, which happened to already be magnetic, but am not getting any improvement in the magnetic field. It seems to be the same, weak size. Am I doing something wrong, or do I just need to step the size up? Thanks!

Posted by Bran 11 years ago


Magnetic Field for hollow core?

I am working on a project in which I have to control a small setup at the end of a motor shaft using an electromagnet. The electromagnet needs to be around the shaft inbetween the setup and the motor. So I have used a metallic ferromagnetic spool(image attached) and wound 32 gauge wire on it to make it an electromagnet and put the shaft through it. Since this core made out of spool is hollow, I'm not sure how the magnetic field will behave. I tried powering up the one I made and it' seems to be both attracting and repelling a magnet's pole (edges attract while centre somewhat repels). Anyone got any idea about this?

Posted by Antzy Carmasaic 5 years ago


Strange Electromagnet Observation

Hey everyone. I'm fairly new to the hobby electronics world, and today I decided I'd build an electromagnet. I wound my coil around a steel bolt, and I used 3 Duracell AA (1.5V) batteries for a power supply. When I turned on the switch, I found that my beautifully wound coil took a little bit of prying to get it off of the metal base I was working on. I thought "Let's try 9 volts!" So I grabbed a Rayovac 9V battery that I had around and hooked that up in place of the 4.4V (measured) bank. The Rayovac measured to be ~9V. The electromagnet was noticeably weaker. When I tested my magnet with just one of my 1.5V batteries, it felt like it had similar strength to the 9V battery.  Can anyone explain what might be going on? Short of that, could someone tell me how to measure the current coming off of each power source?

Posted by TheMike25 5 years ago


creating movement- pulsed coil magnet? other ideas? and how to accomplish?

I'm wanting to swing a small pendulum around (randomly would be nice).  I'm figuring something like is inside this candle would be the best method: https://www.youtube.com/watch?v=XM1c9Ny3X8E However, I don't know where to buy or how to make this (I can make a wire coil, but not program a chip to turn power to it on and off).  The candles are too expensive to buy to take apart.  Does anywhere happen to sell just that piece?  It would be great if I could just buy it, hook it to my 3v power, and I'm all done. Or does anyone have other ideas? Thanks.

Posted by aliasjanedoe 3 years ago


Maglev Train using Electromagnets

I have made a simple maglev train, using Electromagnets. It uses repulsion. and everything is working....except Propulsion. How can I propel it? I can remake the project if required.

Posted by NHarmonia 6 years ago


how far can an electromagnetic field reach?

For my project I need to know how far electromagnetic fields can reach. I am guessing its related to power and materials, but perhaps there is some kind of rough formula for calculating potential reach? By reach, I mean, how far can the magnetic field reach and attract (move) something, like metal fillings. Also, is there anyway to know how quickly a magnetic field can move something. In other words what speed will metal fillings move at when the electromagnet is switched on? Thanks all, Joel (the snow athlete)

Posted by snow athlete 9 years ago


Electronic catapult?

Okay. I'm going to make an electromagnet to hold the spring in place while it's compressed, and then as the power turns off, the spring will release and shoot the catapult. However, I'm not an engineer-- I'm making this for tech class. How should I design the catapult so that this will work as a triggering mechanism? In what way should I set up the spring and electromagnet relative to each other? Thanks in advance.

Posted by camiheall 3 years ago


Help with electromagnet

I have made an attempt to make an electromagnet.I got a 10 inch iron rod with insulated copper wire wrapped around (see image)I didnt have enough wire for the whole rod, so the wire is in two seperate sectionsI tried a AA 1.5v battery, two AA 1.5v, a 9v, two 9v and a big 6v plugged in both ways (negative, positive).None seem to work.I thought it may be the two sections connected together, so i tried all the above batteries again on only one section, and it still didnt work.Can anyone help me out here ?

Posted by oxidase 9 years ago


Selectively magnetized (hemi)sphere

Hi everybody! I'm looking for a way to construct a hemisphere, - maybe 1.5" to 2" in diameter - ideally with no moving parts - where any of a number of areas on the surface could be magnetized at will I thought of having an array of tiny electromagnets starting from middle and radiating to under the surface, but frankly, that would take a long time, and I figure there would be insulation issues. Any suggestions?

Posted by drmab 4 years ago


Electromagnetic field generator

An electromagnetic field generator strong enough that can disturb the tv signal of your neighbour next door

Posted by SalemSnaKe 8 years ago


Electromagnetic pulse generator plans?

Does anybody know where I can find plans for an electromagnetic pulse generator?

Posted by abun1991 11 years ago


Electromegnetic Levatation Glove?

I've seen some devices which use electromagnets controlled by microchips (like this https://www.instructables.com/id/Electromagnetic-Floater/) to levitate small objects. I'm wondering if that same technology could be put into a sort of glove, allowing the user to levitate small metallic or magnetic objects, and maybe even pull or shoot* them? It would have a small electromagnet in each fingertip, as well as a larger one on the palm. All electromagnets could pull upwards on the object if the palm is facing down, and the object was below them. Only the fingertips would pull if it's facing up, and the object is above the palm, (but slightly below the level of the fingertips) The problem would be sensing where the object is, and adjusting the power of each magnet based on that position, and the the position of the electromagnets. *using actual magnetic repulsion would be tricky, but you could, say, have the object sit in the palm of the hand, with fingers outstretched,  then have it attracted to the electromagnets in the fingers, which turn off just as it passes by them. It retains its momentum and shoots out. So, if anyone want to confirm if this is feasible or not (or even want to make it), please post!

Posted by Vick Jr 8 years ago


50k RPM with DIY Motor?

Has anyone built an electric motor that can reach 30-50k RPM? Would you think it is possible to build one?

Posted by Tyoon 5 years ago


Help with trying to make an Arduino-powered MIDI keyboard-controlled ferrofluid pattern-making exhibit!

Hi guys, apologies for the long title. As it says, I'm trying to create a science exhibit that best explains a scientific phenomenon, while being fun and user-friendly. In this case, electromagnetism. Essentially, I want to hook a MIDI keyboard to a USB host shield on a Duemilanove I have lying around. The arduino reads those inputs, and outputs a designated pattern or single pin current to some electromagnets strapped under a tank of ferrofluid. When someone comes by and plonks on the keyboard, pretty patterns SHOULD HOPEFULLY rise and fall in the tank. Attached is a diagram for easier explanation. I have a couple of issues, though. 1. The arduino coding, which I haven't started with. A quick google search returned a post from Circuits@Home, where Colin from MAKE uses a modified PS3 script to recognise USB MIDI inputs. http://www.circuitsathome.com/mcu/interfacing-midi-devices-with-arduino-using-usb-host-shield This is my first real Arduino project. I've only tinkered with the I/O before this, nothing major. 2. A Duemilanove can only output 0.2 watts from a single pin (correct me if I'm wrong). Is this enough to drive a reasonably strong electromagnet? Are there some conditions I need to fulfil? Number of coils, materials for the core, etc. 3. I plan to make the ferrofluid with vegetable oil and toner. Will any old oil and toner do? Most websites come up with a specific variety, but that model usually isn't available in my area. I don't understand toner nomenclature at all lol. 4. Is it possible to wire/program the Arduino to allow a small speaker/synth to output sound, while having the current to power a set of electromagnets? I expect there to be about 12. That's all for now. I'll update if I make any discoveries/progress! Thanks so much!

Posted by cwong14 6 years ago


Prewound Electromagnets

I want to make a wind turbine but I suck at coil winding. Where can I get prewound coils?

Posted by gimmelotsarobots 10 years ago


ElectroMagnetic Pulse Generator

Does anyone know how to make an electromagnetic pulse generator and im not talking about an EMP

Posted by cvm726 10 years ago


electromagnetic gun

Can anyone help me makig an electromagnetic gun, to shoot projectiles at high speed using magnetic wire, capacitor etc, from where can i get a 300 volt capacitor = not from camera =,,,,,,,,,please help guys.......

Posted by ayushdubey12 5 years ago


Electromagnetic and Magnetic Levitation

Hi! I am setting up a levitation system and need to estimate the amount of voltage and current that is needed for a 2" dia. coil to produce 4800 Gauss. I don't have any restrictions/requirements on the core, number of turns, etc as long as it would produce 4800 Gauss with a 2" diameter. How can this be calculated? (I have spent a lot of time googling for such information, but I am pretty confused and didn't find how to calculate this) Thanks!

Posted by J50Nunlimited 8 years ago


Magnet Wire

Cutting open transformers (you might call it an adapter, or charger) yields a good quantity of re-usable magnet wire. Motors don't seem to be a very good source, since the windings on those seem to be saturated in varnish to glue em together. Apparently, vibration is more of an issue in the motors, so they make the windings solid. This might be different in little hobby motors. Dunno.

Posted by Toga_Dan 4 years ago


Electromagnet Amp

I need to build an amp circuit for an electromagnetic signal, but I don't know much about amp cicuitry. I am goin to amplify a 7800 Hz siganl from an mp3 player through a coil. I'm making one of those cart locker things. Any ideas?

Posted by gimmelotsarobots 10 years ago


How do I make an Electromagnet? And a few questions about them and regular magnets?

   I’m looking to learn about electromagnets and magnets. I looked up all those common videos on YouTube of course but It’s not the same as asking people who can tell me directly how to go about making one and things I can do with them.    Here is what I know about electromagnets so far. I know that you wrap wire around a piece of iron neatly (the more times you wrap the stronger it is). Then you attach a battery to the ends of the two wires that are left and then you have a electromagnet. I also know that to much power is bad because it can heat up. I want to make some cool things with electromagnets. So here are my Questions: Center Of The Electromagnets Questions - What is the best thing to put in the center of a electromagnet? - Is Iron the best and if so what is the best type of iron to use? - If different materials will have different effects could you please list them? Wire For The Electromagnets Questions -What kind of wire works best? -Will thinner or thicker wire wrapped more times around make it stronger? -What is a good wire to iron ratio? Power For the Electromagnet Questions -Could I use a DC wall Plug instead of a battery? -If I use a wall plug could I make a separate Positive and Negative electromagnet? Few Random Questions -What materials will that block electromagnets? Which works the best? -What can you tell me about electromagnets that I didn’t ask? Thanks for reading guys hope you guys can help. I check this constantly so feel  free to pour Info in here.

Posted by Rich The Poor 6 years ago


Will this electric generator idea work?

Will this work? A wheel that has neodymium magnets and coil of wire around iron, basically an electromagnetic. next to the wheel is a coil of wire that generates elctricity when the wheel turns, this coil conveys the electricity to the electromagnet through means of copper brushes. On the other side of the wheel is a coil of wire which gets electricity to power things. In my head, id say that the magnet powers the 1st coil then the 1st coil powers the electromagnet which also powers the 1st coil which powers the electromagnet even more. So in my theory, the electromagnetic gets infinitely powerful (till it burns out). So in a way the wheel can be cranked by hand and yet the 2nd coil will get a large amount of energy. Will this work in real life? why or why not? If this idea already exists what is the name?

Posted by alester333 9 years ago


Electromagnetic attraction

The site in exasperating to use. I tried to past my question but it doesn't work either, so I attached it. Please let me know. Thanks.

Posted by Bretina 4 years ago


Looking for an Electrical Engineer and an Angel Investor or a Business Specialist (in SF Bay Area preferably) to partner with on a high dollar ($500M) value project

I am Mechanical Engineer in SF Bay area an have a series of patent pending revolutionary industrial pumps. The project has gone through hydraulic and mechanical design iteration and looks very promising. These equipment require electric hardware and circuitry design as their driving mechanism which is technically a smart integrated motor. So if you have experience and/or willing to get deep in this area that would be very desired. I am looking for motivated and committed partners and will equally split the profit and share of the business. This patent pending project has a potential to grow up to 500 million to a billion dollar; these numbers are coming from the current competitors that have an inferior product!   I'll ask you to sign an NDA before we get going. Please contact me here or at bk.amir at gmail com. Regards, Amir 408 585 8115

Posted by AmirKalantari 2 years ago


Control a Magnet Fidget Spinner with Arduino and Electromagnets?

Hello! I was wondering if it would be possible to control a magnet fidget spinner with Arduino and electromagnets. Any ideas? The basic concept could be something like this:  Take a common 3 bladed fidget spinner and attach a magnet to each blade end. Build an Arduino contraption with a sensor that observes the spinning of the fidget. Add and electromagnet to Arduino. By repeatedly turning on and off the electromagnet with proper timing and observation you should be able to accelerate (or brake) the spinning of the fidget... right? 

Posted by Vesa Seppänen 1 year ago


Slow-discharge circuit for gradually diminishing electromagnet field?

As I understand electromagnets, you wrap a wire coil around an iron rod and run current through the coil. As long as there's current going through the coil, you have a magnet... But when you cut the current, no more magnetism... I want to create a circuit in which a hand crank charges up one or more batteries or capacitors, which in turn discharge slowly through an electromagnetic coil (such that the magnetic field of the electromagnet gradually diminishes) over the course of an hour or so. The overall idea is that you crank the crank for a short while, creating a magnetic field so that BBs cling to the electromagnet. But little by little, over the course of maybe 20 or 30 minutes (longer would be OK), the BBs drop off one by one (or a few at a time). Can anyone suggest what such a circuit might look like? What variables will determine how long the crank has to be turned, how strong the magnetic field will be and how slowly it will discharge? And will the BBs only cling to the ends of the electromagnet? Or will they cling along the length of it as well? 

Posted by Donny Bahama 4 years ago


LIM Question

I have a question about linear induction motors. I can't seem to actually find the answer anywhere. Is one rail a permanent magnet and the other an electromagnet, or are both of them electromagnets?

Posted by puffyfluff 9 years ago


Electromagnet using permanent magnets

Hi All, I'm attempting to make a very small strong electromagnet using permanent rare earth magnets. I want to boost the magnetic field and increase the magnetic force. The magnets are 10mm in length by 5mm in radius. I have 0.4mm2 enamelled solenoid wire for the winding. My questions are, Is it possible to increase the force of a permenent  magnet? Will the induced flux into the magnet compile the force or will the EMF have to be greater to see an effect? Will paralleling two windings make the EMF stronger? As the magnets are small I have limited room to wrap windings so is there a more effective method? Any help would be great!

Posted by JimmyM5 3 years ago


Discharging high amounts of amperage in a very short time.

Previously I asked this question, except I wanted to build an electromagnetic dent puller. But no one gave me specific ideas or instruction of how it could be done, instead everyone told me different ways to pull the dent out, or how the metal looks.. Anyway. I have a lot of copper wire. And I have a bunch of magnets and ferrous cores, iron rods.. etc. I am wondering if I can create a very powerful burst of magnetic energy with a few winding's of copper around a ferrous core. I'm talking enough to push two very heavy objects apart, such as a television or couch... 1) Copper will be wound around about 40-60 times 2) High amperage discharge from capacitor bank 3) Possible explosion or melting wire? Thank you... again

Posted by Justdoofus 5 years ago


Using LiPo batteries in coil guns

Hello all, this is my first post! I have been theorizing for a while about coilguns, and have been doing calculations. here is how it goes: A single Lithium polymer battery can hold up to 3.3 Ah and discharge at about 30c (safely). We multiply 3.3Ah by 30c and get 99 A of continuous discharge. That’s a LOT of current, but, it is still not enough to fire a good projectile. So, I’m planning on having four of these hooked up in parallel to give out 396A. This is quite a bit of dangerous current, so my wiring will have to be gauge-perfect. The magnetic field that this produces is about 9.9 teslas, as  twice much as your average MRI machine. Yes, I’m utilizing a miniature MRI to shoot stuff. If you want to know how much force an MRI puts out, here is a great video to show you https://www.youtube.com/watch?v=6BBx8BwLhqg. I am planning on having a 2,000 turn coil, with the average distance from the projectile being 1cm. The ammunition is going to be BB bullets, which means our cross-sectional area is at least 7.65*10-4m2. Using those numbers, the initial force on the BB is 3,015,030N. This is enough to lift up 25 semi-trucks. On paper, this seems magnificent. However, I’m accounting for about 2% efficiency, taken into account at this step, giving us 60,300N. This is still an enormous force to take to a .5g BB I’m implementing the Impulse to be .05s using standardized E = F * t,  this gives us 3,015 joules of energy. Huh. that’s way more than we should expect. Let’s take into account the 2% efficiency rating again, and we get a more realistic number: 60 joules. 60 joules is ridiculous for a BB pellet. We’ll use Ek = 1/2*m*V2 to solve for V. I got about 1,553 m/s. This is faster than most guns shoot regular bullets. I will be using a 2-stage setup, and will make sure to  use proper electrical equipment. My question to you is; How accurate are these calculations? if I build this thing, what can I excpect?

Posted by bjohnson45 4 years ago


Need some help with Electromagnetic locks, LCD Screen, Smart card Reader and Battery Power!

Hi All, I am designing a locking device (see attached image) that will house a smart card reader, a small LCD screen (roughly 80mm x 20mm) and a small electromagnetic lock that will need to withstand reasonable force. The overall device will be no bigger than 140mm x 80mm x 40mm I would like to know whether a rechargeable battery would be able to power the LCD screen, electromagnetic lock and smart card reader. If so how big and what size would that battery need to be? How would an LCD screen be programmed to take information off of a magnetic strip and display it on the screen? I would also like to know some names for the components that would be required to operate all of these components. Thank you to anyone who comments. 

Posted by jonvjj 3 years ago


hearing electromagnetic stuff

Well, I was going to plug my ipod into some old computer speakers. my thumb touched the tip of the jack (ground) and it makes a buzzin noise. Big woop. No, as I go to reach my ipod it makes a big buzzing noise. what I was hearing was the electromagnetic waves. I reach for my cell phone and then a loud really highpitched noise ccame out. I waver my hand over my computer's power supply, I here a loud buzzing noise. How to do this: press tip of thumb to tip of 3.5mm jack turn your speakers up pretty high waver hand over complex electronics boy, do i have fun mornings, lol, being sarcastic

Posted by guyfrom7up 10 years ago


Electromagnetic induction questions.

OK, this is another one of those questions I should know, but don't.  Mainly because I have never done it before, I have a whim to build an electromagnetic launcher, something table-mounted with a range of around 3-5m (10-15 feet).  I'm not after launching nails through Coke cans. I have been browsing the web, and the designs all seem to be much more complicated than is really necessary for toy. The image below is a scan of my badly-drawn thoughts of how simple it should be. Have I got that right? I plan to use a bunch of capacitors harvested from dead electronics and connected in parallel.  Is there a recommended total capacitance for such a device? If launching a ring, must the ring slide over the ferrous core, or would there be enough umph to launch a ring balanced just past the end of the core?

Posted by Kiteman 7 years ago


Get electromagnetic pulses from a gas igniter

Hi, here I have a common gas igniter like this: http://s10.postimg.org/r55cvgt9l/gasigniter.jpg Well, I removed the circuit from the box, then I shorted the two terminals, using various kind of coils (thick wire, thin wire, in various configurations and with different turns), but seems that this circuit is unable to generate electromagnetic pulses; I've tried to turn on a fluorescent lamp, to cause interferences to a pocket calculator (as I can see in various videos on youtube), but nothing happens. If I remove the coil from the terminals I am able to get nice sparks. So, why this circuit won't work as expected? I miss something? However this is the circuit: http://s4.postimg.org/fgd78werx/ignitercircuit.jpg Please note that I'm aware of the fact that these kind of circuit could be dangerous; I'm taking all possible precautions (I'm using it far from any electrical device, I'm using isolated gloves, and so on). I just want to make this circuit for fun. Many thanks.

Posted by akopelumenuscu 3 years ago


How can we build a cheap detector that senses a cellular (electromagnetic?) for use as a switch for a computer?

Hi all, we want to use a cellular phone as a "switch" to control a multimedia show. We thought of a cheap sensor that must be able to detect electromagnetic waves through a store window. We thought of phones because everyone has one in they pocket, phone is simply the source of the field. Idea is that customers can move their mobile phones in front of our store window to control a multimedia show in a simple way (forward, backward, pause), so in the end three or four different switches glued to the window would perform as a "control pad" for the computer. Maybe there is a way to base this project on products readily available which can be remodeled. Thanks for sour suppport and ideas! Nomax

Posted by nomax 7 years ago


Linear Magnetic Field

I am stuck in my research,please tell me a way to make a linear electromagnetic field,other than making an outer core for it please help me

Posted by ajose4 4 years ago


An Unhealthy Obsession With Magnets

Ever since i observed the attractive/repelling invisible force of the magnet i was interested in this mysterious action at a distance what compels the movement of metal the laws, the principles, wow electromagnetism cool stuff

Posted by eoosen 11 years ago


electronics

I am currently working on a project that requires energy harvesting ,so i decided to use electromagnetic induction for the purpose. However I can not decided how to design my magnet and coil combination. All i know is i want 2.6-3.3v and 26mA for round about 4 ns. The setup in brief required a movable permanent magnet and a stationary coil. The moment of the permanent magnetic is like a oscillating pendulum just for once but with a sleed of say about 15km per hours. So can you please suggest me how should i start designing. thank you

Posted by SiddhantS6 3 years ago


Why to use RF directional couplers in some measurements and control processes ?

I am an electronic engineer in the field of RF directional couplers, but I am puzzled about this question, why to use RF directional couplers in some measurements and control processes ? Today I come to this forum to turn to you to discuss my understandings are appropriate. Here are my personal understandings: RF radio frequency is referred to as RF current, it is a high frequency AC change electromagnetic wave short. Less than 1000 times per second changes in alternating current called low frequency current, more than 10000 times called high frequency current, and radio frequency is such a high frequency current. RF technology in the field of wireless communications with a wide range of irreplaceable role. In the electronics theory, the current flows through the conductor, the conductor will form a magnetic field around; alternating current through the conductor, the conductor will form an alternating electromagnetic field, known as electromagnetic waves. When the electromagnetic wave frequency is lower than 100khz, the electromagnetic wave will be absorbed by the surface, can not form an effective transmission, but the electromagnetic wave frequency is higher than 100khz, the electromagnetic wave can be spread in the air, and the outer edge of the ionospheric reflection, the formation of long-distance transmission capacity (Analog or digital) with high-frequency current modulation (amplitude modulation or FM), the formation of radio frequency signals, through the antenna to launch into the air, the radio frequency of the high-frequency electromagnetic waves.  Long-range radio frequency signal received after the anti-modulation, reduced to the electrical information source, this process is called wireless transmission. Wireless transmission developed for nearly two hundred years, forming a large number of users and product groups, but because of climate change and the impact of surface obstacles, can not transmit the perfect information. Modern human invention of the cheap high-frequency transmission cable (radio frequency line), in order to pursue the perfect quality of information transmission, taking into account the original wireless devices, wireless cable transmission began to pop. Resulting in the concept of radio frequency transmission. If your information source through the secondary modulation, with the cable to the opposite end, the opposite side with anti-modulation of the information source after the re-application, no matter how low frequency, but also radio frequency transmission, if there is no modulation anti-modulation process, The information source is transmitted directly to the opposite end of the cable, no matter how high the frequency, are the general cable transmission. SI --- Signal Integrity Signal Integrity PI --- Power Integrity Power Integrity emc --- electromagnetic compatibility Electromagnetic Compatibility rf - radio frequency RF emc = emi + ems EMI = Conduction + Radiation Emission SI: The Fourier transform shows that the higher the signal rises, the higher the amplitude of the higher harmonics. The MAXWELL equations see that these alternating harmonics produce alternating current at the adjacent line. And even through the space parasitic capacitance directly to another conductor, so these high harmonics is caused by radiation interference (emission) of the main factors; (that the simple point is that the signal rise faster, the more complete the signal, the better the signal quality, But for emi bad) . PI: PCB exists on the number \ \ analog area, high frequency \ 'low frequency region and other different areas and planes, if the partition is not easy to interfere with each other, that is, conduction conduction (conduction). Ps: Excuse me if I was wrong in words or expressions as I am a green hand in the field of RF directional couplers. I need continual learnings. What is your idea ? Do you agree with my ideas ? Any of your ideas would be highly appreciated. May someone would like to help ? thanks in advance.

Posted by maryzhu 1 year ago


DIY spy earpiece

PLEASE HELP! THANK YOU I want to make a SPY EARPIECE, like a hearing aid with an battery inside,a kind of electromagnetic receiver,that will work with an inductive neck loop set. It is too expensive for me to buy one. Another possibility is using a bluetooth neck loop set. It should look like ear pieces on these websites: http://www.tayx.co.uk/wireless-earpiece/default.html http://www.dhgate.com/mini-spy-earphone-wireless-hidden-cell-phone/p-ff808081228c727401228cf8c6982ce7.html Thank everyone who participates in finding out the needed plans to make one and technical plans

Posted by e_nysa 8 years ago


How do I convert an Electromagnetic brake or lock?

Hi Everyone, I've been searching for a small (20 to 30mm Dia) disc shaped EM lock for a project I'm working on but can't find any. This type of lock's function, where when the electrical power is turned on the magnet activates, attracting a pin or plate, is what I need it to do but I can't find them small and flat enough. I then found some 24V EM brakes for a "Duplicator" (copy machine?) on Ebay where the size may be ok but if they were flatter it would be better. From what I understand these work the opposite way. The brake pad is normally engaged ("locked") to the hub by a spring, then when electrical power is turned on, the brake pad separates from the hub allowing it to rotate. Is this correct? Would it be possible to convert the brake into a lock merely by reversing the wiring or would I need to reverse the direction of the winding? Would that work to then attract a plate when it is turned on? Also, how much could I reduce the voltage and have it still attract a metal plate with a decent strength - say from 1/4" away? Thanks for you help! :)

Posted by Bretina 2 years ago


100 hp electric motor

Is it possible to make a 100hp electric ac motor? I have a workshop so all tools are available. Using ndfeb magnets or electromagnets which are efficient for this electric motor any one know about this plz help even small help is admirable .....................

Posted by kacarot 7 years ago


unstoppable energy

Hi there, Is there any power source that never be stopped?  Well, I am thinking of producing energy from the working principle of electromagnetic induction. it can be a charger, so no worries for short battery life (or maybe replace battery). I am lack of idea on how ti get it start.  Seeking for advice.  TQ.

Posted by brian lew 4 years ago


how do i make this work????

I got this from an antuiqe store and i want it to work. when i tryed to hook it up in stead of loosing the contact when the hammer struck the bell, it continuously held the magnetic pull. any thoughts????

Posted by golddigger1559 6 years ago


Help Making a Toaster Lamp

Kats, I need some help making a toaster lamp. Now I know what you’re thinking, “ I always wanted to make a toaster lamp!”. Well now’s your chance to help. In its simplest form a toaster lamp would be a base of a toaster with the top of a table lamp. The lamp operates like a normal lamp by pulling the string or turning the switch. The electronics in the toaster would be disabled or removed for safety reasons. This would be the simplest model. But I would like to build a model where you press the toaster lever down and the lamp lights up. To turn the light off you press the cancel button or press the toaster lever up. Furthermore the light-dark setting on the toaster would act as a dimmer switch for the lamp. The toaster heating elements would be disabled for safety reasons. Now a basic toaster works like this: When you push down on the handle, a plastic bar presses against the contacts and applies power to the circuit board. 120-volt power runs directly through the contacts to the nichrome wires to start toasting the bread. A simple circuit made up of transistors, resistors and capacitors turns on and supplies power to an electromagnet. The electromagnet attracts the piece of metal on the handle, holding the bread in the toaster. The simple circuit acts as a timer. A capacitor charges through a resistor, and when it reaches a certain voltage it cuts off the power to the electromagnet. The spring immediately pulls the two slices of bread up. In the process, the plastic bar rises and cuts off power to the toaster. Some of the problems I’m facing are the voltage to the electromagnet and PC board is about 12 volts. If you bypass the nichrome wires that would send 120 volts to the PC board which would toast it. So we need a way to do that. Another problem is we don’t want the capacitor to cut off power to the electromagnet, that would shut off the light. We could not charge the capacitor by putting a larger resistor before it, I’m not sure how to do this. The ideal solution would be to gut the toasters electronics, replace it with a circuit that does what I want, and the toaster just becomes a façade. Now that I’ve outlined what I want to do are there any electronics wizards out there who can design me a circuit to do this? Thanks Paul

Posted by god1 10 years ago


Draw Blood with Neodymium Magnets.

I was curious if anyone besides me has drawn blood while playing with Neodymium Magnets?   Fortunately, it wasn't my blood..  On the down side, I'm no longer permitted  to play with powerful magnets when my Girlfriend Comes over.   She forgave me, but Electromagnetism is a Sore subject around here.

Posted by John_the_Builder 4 years ago


electric release latch

Hi! I'm trying to figure out how to go about creating a latch where applying an electrical current would release it. Probably something involving an electromagnet. I apologize (1) for the sudden flurry of board posts, and (2) if this is not the best board for this specific question - I know it's not exceptionally techy, but it looked like the best option. Thanks!!!!!!!!!

Posted by Purple Chez 3 years ago


Thor's hammer with microwave magnet

Did you guys see this! I bet one of you could make one too! Pretty cool! Enjoy! Someone Built A Real-Life Thor's Hammer That Can Only Be Lifted By Its Creator http://www.iflscience.com/technology/youtuber-builds-real-thors-hammer-electromagnets

Posted by BLASTFEMI 2 years ago