How to wire a reverse polarity switch

I have an old Rascal 600 scooter that has a seat actuator that will go up but not down. I have tried to find the problem but can't.  It will operate up and down early in the morning when it is cool but later after it warms up it will only go up. I want to wire a reverse polarity switch directly from the 23VDC system(2-12 volt batteries)to the actuator motor. The actuator motor is 24VDC 12.5 AMP. It has a compression load of 600LBS. The motor has a black and red lead. Please include the size or sizes of wire I will need.  Also please be as specific and simple as possible. A drawing would be especially helpful. Thanks a million and God Bless!

Topic by themanpan68   |  last reply


On capacitors and polarity.

(Asked twice already, but for some reason was not visible.) That is sort of a blanket question. I'm wondering: 1) why only some, and not all or none? 2) what (in their physical structure) causes them to have polarity? 3) why do we make ones that have polarity? Is there something prohibitive, like cost, or safety, making it so in the production? (okay, not safety, as may attest anyone who has seen a reversed capacitor explode.)

Question by V-Man737   |  last reply


Polarity Conundrum

Https://www.instructables.com/answers/Polarity-switching-issue-first-one-to-resolve-get/ Polarity switching issue, first one to resolve gets a one year pro membership, if answered by June 03 2012   Ok, here's the issue.  years ago i picked up a wireless remote control kit for automotive use.  It consists of a 12v receiver with 4 sets of colour matched wires.  Basically you can turn on and off 4 devices.  Press button 1 on the remote and a on-board 15A relay activates completing the circuit for one set of wires.  Press button 1 again and the same relay cut outs and the circuit is broken.   These wires are designed to interrupt the negative or ground  side of your accessory with the positive lead hooked up to your power source.  The receivers power is hooked up to the 12v battery.  I even went so far as to open up the receiver and discovered the entire circuit to be potted in opaque epoxy (how rude) so no modding of the circuit sadly... What I can't get my head around is how to utilize this as a polarity reversing unit, or can it.  Now I have messed around with using polarity reversing circuits in a analog style before, I even wrote an instructable on making one with a DIY DPDT switch  Here's the thing, I live in a remote area of the world and do not have immediate access to what most people are used to, so is this circuit possible to be utilized in the manner I am wanting?  I have access to additional standard 4 pin relays if this helps, but not much of anything else. First person that provides a detailed anwser, which results in this working the way how I want, utilizing what I have, by the end of JUNE 3 2012 will receive a 1 year pro instructables membership.  With a possible 3 month pro membership to the one who proves most useful in finding a feasible work around by JUNE 5th 2012.  And sadly using alternate supplies is not an option, "pretend I am on the moon, with no transport available in time". see the pics Note: in the diagram, the green wires are one switch, the blue wires are another.  Their are 2 more sets of wires but these are being used to control other items and are not shown.

Topic by iminthebathroom   |  last reply


How to reverse polarity digitally (with software) ?

I would like to get a DC motor to spin in one direction for a specific number of rotations and then spin in the opposite direction for the same amount of rotations and continue to do this automatically? I know that changing the direction of the motor is achieved by reversing the polarity from the power supply, but how can this be done without using a switch or potentiometer or any other piece of hardware? I am new to this stuff so any help is much appreciated. Thanks

Question by luch   |  last reply


how can i get a 12v motor to automatically reverse polarity or direction either by a certain time or by ???

I have a machine that is for hunting that swims duck decoys back and forth.  See youtube video " home made wake maker " but right now i  have to swith the direction automatically and i need something that i can just turn on and let the decoys swim back and forth without me touching anything.  Anyone have any suggestions?  The motor is a 12v trolling  motor with simple pulley on the top and wires are ran all the way to a box where i have a on and off swith and a switch that reverses the polarity!

Question by stumpman42   |  last reply


IS IT POSSIBLE TO REVERSE A SWITCH?

Im building a multiphase coilgun but encountered a problem. In order to activate secondary phases i need a photoelecric switch. In my case it is TCRT5000 photoelectric switch. The problem, however, is that once the ''beam of light'' is shining on it, the switch is turned on, but i need it to be turned off when ''beam'' is directed at the diode and turn on when the ''beam'' is not directed at the diode. How do I do this? And in this case changing polarities wont change anything.

Topic by mondeluz   |  last reply


How to build a motor reverser?

I have computer fans that I use as fume extractors when I solder. I would like to know if there is something that I could build to reverse the direction of the fans.  On a slightly related note, I have a netbook cooler with 2 fans in it. I have tried reversing the polarity but they won't spin the other way. Can someone help? There are no diodes in the circuit, I have checked. I think it's because the fans can only work if hooked up properly, can someone confirm?

Topic by Wally_Z   |  last reply


Enforcing polarity with an AC adapter?

Several months ago, I posted an I'ble for adding an AC adapter to something. The adapter I chose, from Radio Shack, is actually a two-piece "kit" -- the wall wart cord ends in a generic two-pin female jack, and they sell a bunch of different end plugs. The jack is symmetric, so that the end plug can be put on with either ground or hot on the outside.I've just realized that this could be a problem. If the electronic device expects red to be positive and black negative, then putting the jack on backwards would be equivalent to installing all the batteries the wrong-way about. Not a great feature.To "protect" the device, I'm considering adding a diode bridge to ensure that the internal "red wire" always carries the positive, and the "black wire" is always ground. Do more experienced folks consider this a good idea? Is it necessary? Would it be better, perhaps, to just epoxy the end plug so it can't be reversed?

Topic by kelseymh   |  last reply


Why do some capacitors have polarity? Answered

(Asked once already, but for some reason was not visible.) That is sort of a blanket question. I'm wondering: 1) why only some, and not all or none? 2) what (in their physical structure) causes them to have polarity? 3) why do we make ones that have polarity? Is there something prohibitive, like cost, or safety, making it so in the production? (okay, not safety, as may attest anyone who has seen a reversed capacitor explode.)

Question by V-Man737   |  last reply


How can I reverse polarity using 2 switches?

I am trying to reverse polarity on a small 12 v pump. I currently have 2 SPDT switches and have them hooked up like a DPDT. I am getting voltage feedback when they are in the off position. I need to have t switches any help?

Question by craigbalex   |  last reply


How to wire an actuator to reverse polarity with relays only, no switchs?

I'm using the L12 S Firgelli actuator in my project. If I applied 12v and Ground to respective leads the actuator will expand if I reverse the wires the actuator will retract. I need this: When I turn my car on the actuator will expand and when I turn my car off the actuator will retract. How do I wire the relays? Again I don't use a switch. Thanks

Question by kpitao   |  last reply


How to reverse the rotation of a vacuum cleaner motor? Answered

I'm possession of a vacuum cleaner engine and I'm trying to reverse its rotation..So far I've tried reversing it's polarity with no success but I looked up the 2 ICs on it's chip and it has a555 timer and a 7-stage binary counter.(see: http://www.standardics.nxp.com/products/hef/datasheet/hef4024b.pdf)There are only 2 wires running to the engine from the chip so I presume there is no feedback.Furthermore there is a potentiometer hooked up to both the ICs which regulates the speed of the engine (and no AD convertor as far as I can tell) so the voltage changes the PWM output as the engine is rated 230V.All ideas are welcome =)p.s.(I can't supply you with pictures right now, sorry)

Question by Prodigity   |  last reply


Does this switch exist? Answered

It may just be my google-fu failing me, but I can't find switch I am sure must exist: A sliding switch with reversing (DC) polarity. At one end of the slider, power is full "forward".  Slide the controller, and power decreases.  Reach the centre, and power is zero/off.  Slide past the centre, and power increases again, but with reversed polarity, ie in reverse.

Question by Kiteman   |  last reply


how to reverse the polarity of a DC motor using a DPDT relay, limit switch, and timer?

Ok, i am not an electrician and understand very little, but here's what i want to do.  I have a reversable 18V cordless drill I have taken apart to get at just the motor.  What I want it to do is turn on automaticallly with a timer in one direction and shut off (with a limit switch?) after about 2 seconds.  About 14 hours later I need the opposite action. Both actions automatic using a timer with AC power.  The application is a door opening and closing veritcally (chicken coop door).

Question by StevesBees   |  last reply


How to fix CRT monitor that has been powered with reverse voltage?

I have a small Homeland Security system monitor (model number 01875) that I accidentally powered with backwards polarity. Now it doesn't turn on. How can I fix it?

Question by Ethanal   |  last reply


How can I using a MAME Joystick (Happ Joystick) with a reverse polarity motor?

I'm trying to use a Happ Joystick to control 2 reverse polarity motors. (But for this will just talk about one motor) If the joystick is pointing up the motor should go clockwise (+ -) If the joystick is pointing down the motor should go counter-clockwise (- +)I would like to use the Happ Controller because it's an 8-way joystick. Because of the happ joystick is meant to work, I know I need some sort of realy somewhere, I just don't know where. This will be connected to a 18 or 12 volt DC power supply. This is something very similar as the Simple wired 2 motor control joystick. But I'm looking for something a little more larger, robust, and can handle abuse. Thanks for any help.

Question by NateMac   |  last reply


How can i get a 12v motor to automatically reverse polarity or direction by a adjustable timer ???

I have a machine that i built for hunting that swims  duckdecoys back an forth that mimics a live group of ducks and would like to control it by an adjustable timer to automatically reverse the direction of the motor  instead of having to hit a switch back an forth.Heres what i need exactly a timer that is adjustable by a knob that will switch direction of motor after a certain time an adjustable speed control by knob for the motor to speed up an slow down the motor an a on/off switch to turn the system on an off if someone could help me with a parts list and a schematic of how it all goes im shure i can figure it out

Question by frankswamper   |  last reply


Is there any way to reset or an inside fuse to change on a TomTom navigation device? GPS 300?

The device was connected in reverse polarity. Pilot light is on but all else is dead.

Question by D.T. Hammer   |  last reply


how do i reverse polarity to/control a "hobby" servo using an arduino chip and motor shield?

I am new to programing and electronics/circuits i.e. breadboards etc, and i have been looking around on this website and YouTube to reverse the polarity to a linear servo motor to make it go forwards and backwards. i am also having with the servo going to far forwards and backwards and locking up the motor to the point where i have to manually spin the gears to free the motor, how do i fix this? The servo/motor i am using is a AS2000L 1.7- Gram Linear Ultra-Micro Servo and i am using 2 types of this servo, one with just positive and negative wires and the other is the full version with the chip and receiver/transmission wire here is the link for the servo,http://www.spektrumrc.com/Products/Default.aspx?ProdId=SPMAS2000L the specs for it that are on the back of the package are: Torque: 2.8oz of force Speed: .14 sec @ 3.7V Dimensions: 22 x 16.9 x 8.2mm Weight: 1.7g Voltage Range: 3.2V - 4.2V Stroke: 9.1mm Connector Type: JST In the beginning i used a 9V battery and just switched the ends that the wires touched and that was how i was reversing the polarity, now i am using the same method but with 3 1.5V  AAA batteries connected together.

Question by THE STIG37   |  last reply


How does this 5 pole switch work?

I took apart a broken DVD player. I wanted to possibly use the tray mechanism for a project. It appears that the DVD player uses a 5 pin pcb mounted switch to reverse polarity for the motor. I can of however figure out how to wire this and make it work. How does this 5 pin swith work to switch the polarity of the motor?

Question by MDheliMech   |  last reply


Can Anybody Help me with Audio Terms?

I am on my way to build 3 way speaker system and this my first time. I heard that i have to make crossover into the speakers which will drive the low frequencies to the woofer and mid ranger whereas the low pitch to the woofer. I went to a site that calculates schematics for any sort of crossovers. But they ask me the several things out of them i understood some of them while others made my mind disrupted. so please state the meaning of the following: High Xover Frequency ( fh ) Low Xover Frequency ( fl ) Frequency Spread ( fh/fl )   here there were 2 options I.E, 8:3 octaves and 10:3.4 octaves Bandpass Gain ( g ) Crossover Type In the last one there were several options: 1st Order normal polarity 2nd order reverse polarity 3rd order reverse polarity 3rd order normal polarity 4th order normal polarity What are the differences between these crossovers? Which one is the best and why? If nothing is best so what is the difference? Sorry I am a novice. So guys please be easy on me....  Thanks In Advance :-)

Question by adarshnarsaria   |  last reply


Transistor Trouble

Hi there, I have been working on controlling a large toy car with a wireless receiver from a smaller toy car, the motors I need to control are rated for 9V but the receiver only outputs 3V, reversing polarity to reverse the motor. I made this schematic using transistors to handle the voltage, but when I built the circuit the transistors began to heat up and there was no output. I am not sure why this is happening, so any help would be greatly appreciated. Thanks, Daniel

Topic by daniel12354   |  last reply


Did I screw up my power converter?

My motorhome has a115v ac to 12v dc with a split transformer, the 2 outer leads went to press in diodes and the middle lead went to neg or pos.(cant remember witch)  it is 40amp converter. one of the diodes was bad and i was only getting 6 volts out so i replaced them both with 40 amp 600 volt ZENER diodes. Are the zener diodes the wrong type to use, all seemed good except my neg and pos polarity were reversed coming out of the power converter, I reversed the terminals at the hook up so polarity would be correct.  Could this discharge my battery when its not connected to 115v.                                                                                             Thank you, Duncan

Question by dsr.   |  last reply


What or which PNP Complementary transistor can I use with a N-Channel IGBT HGTP10N120BN 35A 1200V NPT Transistor ?

What or which PNP Complementary transistor can I use with a N-Channel IGBT HGTP10N120BN 35A 1200V NPT Transistor ? I can't find a 1200v PNP transistor. Ed.

Question by DELETED_applegoose   |  last reply


Is it possible to use a 75MHz am radio receiver with a 27 MHz am transmitter if i match the crystals?

I fried the 27mhz receiver by accidentally reversing the polarity and i had the 75mhz laying around.  I was wondering if putting the 27mhz receiver crystal in the 75 mhz reciever would work.  Thanks in advance for your answers.

Question by jules15   |  last reply


Will this circuit work out of curiosity?

I saw a question, https://www.instructables.com/answers/Need-help-with-the-wiring-diagram/ that asked about making a relay circuit that is capible of moving or rotating something to one extreme, then stop, and reverse direction to go the other way, but what intresting is that there is also supposed to be a delay in it, so it goes all the way in one direction, stops for a moment, and reverses direction and stops, then reverses... you get the idea. That question intrigued me, as I like really basic and elegant solutions that do not use a raspberry pi to do such a demeaningly simple task! I can see something like that being used for an automatic door w/ one button operation, and I decided to see what I can come up with on my own with a few relays on paper. Here was my solution. However, although I have traced it all out and it seems to be functional, can anyone else verify that? When I get the parts, I will actually try to build a scale model to and see how well it works (after all, thats the best way to discover problems! The physics engine of real-life is never wrong :) ). I may modify it so it just uses a "open" and "close" switch instead w/ the limit switches. (a bit more practical for that use.) But I wanted to challenge myself with those requirements instead. The idea here is that I have 2 DPDT switches, the 1st one will be a latch, and the second one will change the polarity of the motor. There is a giant RC circuit on the output of the 1st relay which delays the changing of polarity to the motor using the 2nd relay (as an H bridge), and the limiting switches control power to the motor in one or the other direction, (so when one limit is hit, the power cannot continue to flow through the into the motor, so it does not keep trying to push the switch off, but still must allow the polarity to be reversed and let the motor travel the other direction to the other side, so it does not freeze up right there. Thats needed because the same RC circuit which delays the polarity switching is 'laggy' and the capacitor takes time to discharge, and it will continue to try to press that motor into the switch until the capacitor has discharged fully though the relay coil. Just not good engineering practice.) 

Question by -max-   |  last reply


Do audio devices put out alternating current? Does the current ever switch itself?

Hi I'm making a prop Geiger counter for Halloween, and i was going to have bi-polar LEDs on it depicting if it is safe or not to proceed. I have worked out all the main issues with making a prop Geiger counter, Producing the sound, amplifying it, and distributing it. I was going to have one channel of my MP3 player play Geiger counter clicks and the other  channel square waves to drive a transistor to drive the Bi-polar LEDs I was going to have Red LEDs light up to the positive part of the wave, and the Green to the negative. This is where i ran into a small problem, i don't really remember if Electronically produced sound waves have both Parts of a wave (look at the picture), or of it just produces a positive pulse without reversing polarity. I will be using a computer speaker amplifier for this project Thank you! (basically, i need to know if Computer speaker amplifiers produce AC current)

Question by Sandisk1duo   |  last reply


How to convert an air pump/vacuum into a two mode machine which can blow and suck? Answered

Hi, I'm trying to build a simple robot gripper under a budget using this idea http://makezine.com/projects/universal-robot-gripper/. So from what I understand I need a vacuum cleaner that can change into an air blower with a flip of switch using the same nozzle. Is there any cheap option where i can make something similar? I was thinking of buying a cheap car vacuum cleaner or a cheap air pump and reverse the mode by reversing the motor polarity. Will that work? Really need a quick answer for my project, please help. Thank you! 

Question by KhayhenS   |  last reply


DPDT Timer circuit i.e. Momentary ON (+6v pulse) then OFF for 10 sec's then Momentary ON (reverse pulse)

I need to toggle a solenoid between 2 positions. It isn't spring loaded so needs to be powered between states i.e. a +6v and GND pulse to the coil then wait 5 to 10 sec's before sending another pulse but with the polarity reversed. Simple to do with a 'Mom-OFF-Mom' double pole double throw toggle switch e.g. JAYCAR Switch Tgl Mini CTR-OFF DPDT MOM CAT.NO: ST0358 but I would like to be a bit more automated.  Ideally the cycle will start at power on and then automatically repeat every 30 min's or so but if that makes it too complex, then a momentary push button switch could be included to manually initiate the cycle.  

Question by DavidB687   |  last reply


how do i even out my dual gearbox? Answered

I have a tamiya dual gearbox hooked up to a tamiya tank base. i found the one side's track goes faster that the other.. how can i fix that? i tried reversing polarity but the same side goes faster... i have the motors hooked up in series.. thanks!

Question by Chowmix12   |  last reply


How would you use a standard servo and linkage to raise the visor of a repro Ironman helmet?

I am thinking that I could use a standard servo (or 2) to do the raising of the visor incorporating a DPDT switch to reverse the polarity to bring it back down again. I am struggling with the translation of the rotary action from a servo to push the visor out and up.. What would be the best linkage to use? what would be the interface between the servo and the linkage

Question by Deathbird   |  last reply


12 volt relay help please?

I just purchased a set of electric running boards for my truck. i have to make my own wiring harness. the problem i have is, i need to wire a relay to each running board. i need the relay to power the motor down when the door is opened  and is triggered by the door ajar switch which isnt to hard to do. the hard part is to have the relay reverse polarity so that the motor retracts the running boards when the door is shut and  the signal is lost from the ajar switch

Question by Gearslamer   |  last reply


Polarity switching issue, first one to resolve gets a one year pro membership, if answered by June 03 2012? Answered

Ok, here's the issue.  years ago i picked up a wireless remote control kit for automotive use.  It consists of a 12v receiver with 4 sets of colour matched wires.  Basically you can turn on and off 4 devices.  Press button 1 on the remote and a on-board 15A relay activates completing the circuit for one set of wires.  Press button 1 again and the same relay cut outs and the circuit is broken.   These wires are designed to interrupt the negative or ground  side of your accessory with the positive lead hooked up to your power source.  The receivers power is hooked up to the 12v battery.  I even went so far as to open up the receiver and discovered the entire circuit to be potted in opaque epoxy (how rude) so no modding of the circuit sadly... What I can't get my head around is how to utilize this as a polarity reversing unit, or can it.  Now I have messed around with using polarity reversing circuits in a analog style before, I even wrote an instructable on making one with a DIY DPDT switch  Here's the thing, I live in a remote area of the world and do not have immediate access to what most people are used to, so is this circuit possible to be utilized in the manner I am wanting?  I have access to additional standard 4 pin relays if this helps, but not much of anything else. First person that provides a detailed anwser, which results in this working the way how I want, utilizing what I have, by the end of JUNE 3 2012 will receive a 1 year pro instructables membership.  With a possible 3 month pro membership to the one who proves most useful in finding a feasible work around by JUNE 5th 2012.  And sadly using alternate supplies is not an option, "pretend I am on the moon, with no transport available in time". see the pics Note: in the diagram, the green wires are one switch, the blue wires are another.  Their are 2 more sets of wires but these are being used to control other items and are not shown.

Question by iminthebathroom   |  last reply


Motor triggered by a vibration sensor

Hi, my project consists of a vibration sensor that, when enabled, will trigger a motor which will function for a certain amount of time, then stop, and stay in this position as long as the sensor is detecting vibrations. When the vibrations stop, I need the motor to reverse polarity and function in the opposite direction,for the same amount of time as before then stop, and repeat... I'm a first year electrical engineer so please consider me a rookie in this field. If someone could provide me with a suitable electrical circuit, with names and values for the part, i think i might be able to draw the corresponding board. Thanks

Topic by julienfhd   |  last reply


Shocks w/ electro magnetics

Hello Every one this is my first post, and since I am a full time student, full time para legal and full time parent, I'm just going to throw this idea out there and let others build on it. Its just an idea that I have had for years. Concerning electro magnets and shock absorber for your average car. Let me know your thoughts. My main thought is that the magnets would be working with reverse polarity add in electricity and you have a pretty good repelling force for going over those bad Jersey roads. Let me know your thoughts.

Topic by arkburn   |  last reply


How to wire 12v dc case fan to 1x9v and 2xAA batteries? Answered

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


how to make an electromagnet thats a circle be positive on one side and negative on the other?

Im basically trying to make an electromagnet that will wrap around a tube of metal and i want to have it magnetize the inside of the metal tube and on the left (as your looking at the tube from the side) its has positive attraction and on the right it has negative push that is my question and if anyone could tell me how i could do this that would be EXTREMELY appreciated... not only that but if i could reverse the polarity so left is negative push and right is positive attraction that would be great to please help its for a science experiment and would be GREATLY appreciated 

Question by ShinigamiTentetsutou   |  last reply


Voltage regulator Design Problem?

 Ah, voltage regulators. Easy Right! Not this one. I am making a voltage regulator like for an automobile regulator for a DC generator. (I'm replacing the old DC generator regulator on Pre 60's cars) A battery is charged from a winding on a Generator  (20V @ 60 Amps) A voltage sensor on the battery voltage turns on and off a switch driving the Field winding. The Field winding basically "turns on and off" the generator output. The battery is connected directly to the generator. (Why  and Why not is coming up) But when the Genrator's output is lower than the Battery voltage, current will flow back from the battery to the generator winding and discharge the Battery. So I need some isolation between the generator output and the battery. Alternators are easy since it has a bridge onthe output keeping the current from flowing backwards. Old regulators used a relay which burned out sooner or later. So easy, use a diode right? Just put a diode inseries with the generator to the batery. By the way, the "open circuit" voltage on a generator is about 200VDC No! The best diode I can find has a .7V drop at 60 Amps which is 42 Watts of heat to dissipate. Ahhh, so use a FET, They can get down into the milliOhms right? Except for the reverse polarity (and ESD) protecton diode always across the FETs defeat the purpose of a reverse polarity switch. So who out there is smarter than me? What goes inthe box marked ?? Any solutions accepted. Ungefahrt (now neither young or fast)

Question by ungefahrt   |  last reply


what diodes do i need? Answered

I made a litle schematic (picture is in paint) as an extra for my binary clock, since the wart is a litle bit to handy (i can reverse polarity) and i dont want to destroy my precious attiny2313, so i thought of of some diodes and made a plan. but, i had 4 zenerdiodes lying around, and i tried it, but nothing happened, the clock didnt power on. i think the diodes are to heavy, so i was wondering which ones i needed. its all in the scheme and i think its pretty obvious (i made it in paint, so the quality isnt good, as wel as my english :P)

Question by godofal   |  last reply


help with shorting probem on my curcuit

This circuit does not work because of a problem with power shorting to ground at the motor. I think that is the only problem. The servo provides a 4.5v power source and the polarity can switch allowing the original 4.5v servo motor to run forward and reverse. I am making this to run a motor on 12v and the servo on 4.5v. R1 keeps the transistor saturated and the R2 is in there because I read it would help the transistor turn off completely. I made this circuit work (the right voltages went to the right places) in one direction but now it is more complex, I think I’m having a shorting problems. Can anyone help?

Topic by kendallickes   |  last reply


Can I use an old floppy disc motor to make a small wind turbine for my solor lights? or an old hard drive motor ?

I want to put some propellers on a PC fan motor or an old floppy drive motor and make free electricity, enough to charge my garden solar lights. I have tried connecting leds to an old printer motor and spinning it, the back emf lights the led for a second. spinning the other way lights the other led in reverse polarity to the first.... My problem is that the motor would continue to spin in the same direction in the wind...only generating electricity for a split second........ Pleeeaaaase help me!

Question by niceribs 


How create a detailed motor controller using an arduino motor shield with the uno? Answered

Hi, i'm new here and new to the arduino. I am using an arduino motor sheild and the uno board to contol a 4v dc motor. I want to be able to make the motor spin forward as well as reverse the polarity and make it spin in the opposite direction. Also using four inputs, preferrably push buttons, I need it to increase the motor speed by 5%, decrease the motor speed by 5%, make the motor speed 25% of max speed and make the motor speed 50% of max speed. Code examples would be really helpful. Your time and help are greatly appreciated.

Question by beginnerbot   |  last reply


DIY WiFi Helical Antenna impedance Problems

First off, I live in the states, but I absolutely hate the imperial system of measurements. I will try to use the metric system as much as possible.I have been attempting to follow hanzablast's Helical WiFi Antenna, but have run into a few snags. I have most of the parts and have a few problems concerning it.1. Instead of a Type N connector my USB card has a RP-SMA connector. Do I have to do anything special (buy a special panel mount/ reverse the connections along the wire) because it has reverse polarity or does it not matter?Edit: I feel foolish, Doing a quick wiki search on Reverse Polarity SMA I found out what it means. Turns out WiFi companies reverse the gender of the inner pin in their connectors. So either I have to find a RP-SMA panel mount jack, or buy a RP-SMA Male to N Male Adapter and a N Female Panel Mount. The latter of the two seems more efficient.2. I understand that having too small of wire can have a detrimental effect on efficiency, but what about using a much larger wire (instead of AWG 16 gauge wire using AWG 4 gauge wire)?Edit: Answered By NachoMahma3. I am having trouble locating a SMA right angle 4-hole solder point panel jack mount other than in bulk buys. Does anyone know where to purchase one separately? Edit: Answered By NachoMahma, but has become a null point.4. I am having a problem with the impedance matching. I have seen several different ways to connect the antenna (142.68ohm impedance) to the SMA Jack (50ohm impedance). I've seen half and quarter circumference turns, quarter wavelengths turns, and triangular strips of copper. Which is best?Edit: I did the math and read my friend's ARRL handbook. Supposedly, a 1/4 wavelength turn of a metal strip with an impedance of 84.463 ohm is what I need. Using TraceSim I figured that I can use part of the copper plate with a size of 12.79033mm in width, 30.775mm long (1/4 a 2.437GHz wavelength), and 0.406mm (.016") thickness placed 8.03mm (1/4 distance between coils) above the reflector plate will give me the exact impedance I need.

Topic by AllAgainstPaul   |  last reply


solenoid actuator and led momentary push button door locks

I have a car door lock 2 wire actuator one wire pushes the solenoid actuator to unlock and the other wire pulls to lock. I want to install these in my car with a momentary push button switch which illuminates when doors are locked and button is pressed once and then turns off when doors are unlocked and same button is pressed again. Should this be a dpdt on off on switch, or spdt on off on? I know with rocker dpdt switches you can set it so reversing polarity will make the actuator pull or push whichever the opposite is. Do they make a push button that I can press to lock, press to unlock.

Topic by graphitej   |  last reply


How to rig a capacitive touch to a usb keyboard (or gamepad)?

I need to make a touch sensitive (capacitive) button that triggers a key. I got a capacitive demo board from qprox that should be fine...I touch it and I can hook it up to an LED that gets lit. But if I try to put the wires from a button on a gamepad to the out of the demo board, the button is constantly in the "Down" state. I think I remember reading somewhere about a polarity reverser or something so that it reverses the On and Off state, but not sure what I need. Also, the demo board is powered via a small watch battery which is perhaps conflicting with the power from the USB? I'm not quite sure the best way to do this. I think I can power the demo board using the USB power rather than the battery. I also would like some advice on creating the Capacitor to a 3" button surface are that goes through 1/4" glass. I've got a resistor that upped the Qs so that it works through glass, but not sure how to make it fit to a desired "button" shape.

Question by superjames   |  last reply


help understanding this switch

Hi im trying to salvage a dvd drive for a project im working on but i dont seem to be able to replicate how the switch works i can get the drive to open an by applying 5v to the + and - and then reversing the polarity to close the dive but the motor will continuously run until the power is disconnected  so i guess this is where the switch comes in, excuse the picture! i assume that when the momentary button is pressed the switch moves to stage 3 and  allows power to the motor until the switch reaches the next stage where power is then cut off, when the momentary button is pressed again the switch moves back to stage 3  which swaps the polarity and again allows power through, and that cycle carries on each time the momentary button is pressed. stage 1 the dvd drive is closed the swith stays in this position stage 2 the dvd drive is open the swith stays in this position stage 3 the dvd drive is either opening or closing the switch moves to this position when the motor is in use  i have a 5v power supply how would  i wire it up to get it to work properly? it seems like it should be easy enough but either im missing something or im just not getting my head around it properly,

Topic by AbleArcher83   |  last reply


How to boost voltage of signal generator frequency? Answered

Okay, here's the question/challenge... I'm using an AD9850 signal generator IC to create various frequencies which works great. Input voltage is 5-volts. However the output is only around .5-volts. What I need is to be able to boost that to (ideally) around 45-volts without affecting the frequency created. The ultimate amperage I am working with is only 20-600 microamps so the boost shouldn't be a problem (I think). I've independently used voltage boosters but wonder if those affect the frequency. Then from there I want to make the current biphasic (reversing polarity every 3-5 seconds) so I'm assuming a relay somewhere at this end. What say the resident experts here?

Question by pletchman   |  last reply


Announcing the Roboduino - the ultimate Arduino-compatible Microcontroller

The Roboduino is finally on sale!!!http://curiousinventor.com/images/kits/roboduino/roboduino.jpgIts $40 for a kit and $55 for an assembled version More info and sales information here: http://curiousinventor.com/kits/roboduino Features / Specs:100% Compatible with Arduino software.Power buses along side pwm and analog pins easily accept standard servo and sensor connectors.Powered can be supplied from USB, barrel plug or 3-pin male header. You'll need a suitable power supply when driving multiple servos.dedicated UART 3-pin male header6 PWM outputs with neighboring unregulated power pins6 analog pins14 digital pinsReverse polarity protection for board circuitry (not for unregulated power pins)Optional I2C pull-up resistor locations

Topic by Erobots 


is there an easy way to manually operate a cd tray?

Im in the middle of automating my trash can (i know i can just buy one, but what's the fun in that?) and i got the proximity sensor part to work, but i cant think of a way to turn a short burst (in the sensor test circuit i had the led on the output blinked once when my hand got close yay!) into a signal that would power an old cd motor until it opened, pushing the trash can lid open, wait about 10sec or so, then apply reverse polarity for 2sec or so until it closed. i might be able to use a microcontroller to do this, but im just getting into that and i don't want to use one for this unless there isn't another way. if it's relevant im using a 555 to generate a 38khz pulse to an ir led picked up by rpm7138. any ideas?

Question by the judge   |  last reply


How to wire 2 wire actuator with 2 wire Dc adapters as 3 way switches Answered

Trying to figure out the wiring to operate 1 actuator using 2 on/on switches. Anyone care to help out? Actuator has built in limit switches. 24" stroke. It will open all the way and door will be closed and then open all the way when the switch is triggered on either end. Same as a hallway light that operates from 2 location in the house. The tricky part I've found is getting relays and switches to reverse polarity. I know how to wire a dpdt switch to move forward and backward on the actuator. But with another switch to do this I've been told I need relays. I don't understand the circuitry and tech talk, so please bare with me. Pictures say a lot, so if you can add photos or links that helps most.

Question by nowrydell   |  last reply