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Polarity on speakers? Answered

I have about a dozen little 4-8 ohm speakers out of toys and alarm clocks. I noticed that while most of them have no markings, one of them has a little plus and minus polarity markers on it. Does polarity matter on cheap speakers, and if so, why?

Question by Michael_Bell    |  last reply

polarity tester

Hi, if someone can help me how to construct such a tool polarity tester Thank you in advance for helping

Topic by is4neno2    |  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

invert polarity? Answered

Hey guys, please could you help me?  i trying to do external battery pack to run pedalboard with 4 effects. As far as i know Boss pedals have center negative type of connection. Can pls somebody explain what does it mean? Whether it means that leads are inverted positive goes to the sleeve and negative to the tip? Or tip has to receive negative voltage of minus9V? thanks !!!!

Question by IgorA26    |  last reply

Polarity Conundrum

Https:// 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

Changing polarity

Hi everyone, the problem I have is probably wither really simple or really complex.. .but either way here goes: I have scavenged an old CD-ROM drive for parts, namely, the motor and gears which move the CD-ROM door in and out (depending on the direction the current/voltage is flowing). I want to setup a system where upon flicking a switch (either SPST, SPDT, etc, whatever is needed) in one direction, the tray ejects, and when flipped the other way, the tray loads. In essence, I want the current/voltage running in opposite directions depending on the position of the switch (Up, one direction; down the other direction, and center, off). If necessary some indicator LED's and additional switches could be used... but I don;t really know where to go from here.. .any help would be GREATLY appreciated. Peter

Topic by Murf    |  last reply

Polarity of tantalum capacitors

Howdy all, Recently got back into basic electronics and have started building kits. Been building a kit that uses tantalum capacitors and it notes that polarity orientation is very important. The question I have is: is there some un-published indicator of how polarity is indicated on these tantalum caps? I've been over these things with a microscope, even bought new ones, but other than the values & manufacturer, I can find no obvious sign of polarity. Leads are the same length and not marked. What am I missing? Thanks in advance for any help. Dave

Topic by gutbucket    |  last reply

Non polarize capacitors?

I would like to know two polarize capacitors joining negative to negative whether can be use as a non polarize capacitor. Thanks.

Question by tuanb    |  last reply

Polarized Lights and Laptops

I was taking apart a laptop's LCD screen and found that sandwiched between the light source and the liquid crystal display were what appeared to be a vertical and horizontal polarized filter. Why is this? I always got the impression that LCD displays had the polarizers attached to the screen itself. Why would there be an extra set of polartization filters behind the screen? Or... am I just plain wrong in thinking the polarization is on the LCD itself? Could these be the only polarization filters? I have searched all over the internet for the answer to these questions, but I think I am just more confused. If these are extra polarization filters, the only thing I can imagine that they are doing is making the screen darker. Any ideas?

Topic by randofo    |  last reply

Polarity of fan motor?

Recently I had occasion to change the small fan that cool the aluminum fins just above the exturder. Not paying too much attention to the polarity of the 12 volt supply voltage, I figured that if was turning the wrong way, I could easily change the plus and minus connection. When I fired up the controller, I thought it was turning the wrong way and I changed the polarity. It then wouldn't turn at all. Changing it back to the original polarity, it worked fine. It is normal to have the fan polarized, and if so, what is the proper direction of air flow?Alan

Question by agil0629    |  last reply

guitar cable polarity?

On a guitar cable what part is positive?

Question by michoi    |  last reply

Neutron polarizer instructions? Answered

I need some kind of instructions for a Neutron polarizer or a quadrupole magnet. I need some divece to turn ions or alpha particles into electricty directly. If anyone finds something let me know please.

Question by Tobor 2.0    |  last reply

DC Polarity Shifter / changer

Require assistance to build a device to change the polarity of 13-14 volts 30 amps with an adjustable timer. Any help would be appreciated.

Topic by NickMac    |  last reply

Is it possible to polarize a laser pointer?

Would it be possible to polarize a laser pointer and still have it retain it's usefulness?

Question by karate5662    |  last reply

Question about a flyback's polarity Answered

Hello, I am confused with this flyback transformer I have. I have a pulsed DC input on the primary coil (pulses from 0 to 15V) and that creates high voltage in the secondary coil. When I connect that input in the opposite direction (wrong polarity) I don't get high voltage any more. The possible explanation for this is that the primary coil has a diode in series with it. Now, I'm confused by this because I tested if there actually Was a diode in there (by connecting a DC supply and a DC motor, in series with the coil) and the motor always works! (also tested with a halogen light) I put the coil in series with the motor to test if there is a diode inside. If there would be one inside, the motor should not work in one of the two cases, when I switch the pins of the primary coil. So, as the results of the test tell me: there is no diode in series with the primary coil. could it be possible that there is a diode in parallel with the primary coil? If that's not possible, how come the flyback is not working when I connect the polarity incorrectly? Could someone please help me out with this? Thanks, Electorials

Question by DELETED_Electorials    |  last reply

Change polarity to motor on power on?

I have just got myself a set of electric blinds and wanted to make my own controller for them.  To control them I would like to use an X10 Appliance module. So at dusk, the X10 module turns on and lowers the linds then powers off 45 seconds later. Then at dawn the X10 module powers on and raises the blinds, powering off 45 seconds later.  So, I am looking for a DPDT to latch in opposite directions each time there is power applied.  I've looked high and low and cant find a simple solution, and was wondering fi somebody could help please? Many thanks in advance

Question by merseybear    |  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

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

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

Harbor Freight 9 LED polarity.

Https://!!/I want to use that flashlight, and mod it to a different colour led but I need to know if the pbc board has polarity.

Question by Noodle god    |  last reply

Switch electric polarity back and forth at least several times per minute?

I've seen a polarity inverter switch, but is there an automated version of one available that would switch the polarity continuously back and forth without needing to do it manually? Thanks

Question by nlogic    |  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 The Insulated Wire In An RCA Cable, The Negative or the Positive One?

I was just trying to build an RCA to USB cable but I am not being able to find the polarities! Please HELP!

Question by mraghib    |  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 to check the polarity of a micro oven transformer?

I have three micro oven transformer, which am using to build a tesla coil. unfortunaterly am in a state of confusion in knowing the polarity of the transformer...:-( so i need some guide to tell me how to check their polarity.....?

Question by richardsbabu    |  last reply

Help to build sensor for Polar FS1C watch

Hello, I got this watch Polar FS1C as a gift, unfortunately without sensor which is necessary to collect data from heart rate. I would like to ask you, clever guys, if is it possible to (home)made cheap sensor suitable for Polar FS1C? I could not buy this sensor in Slovakia in reasonable price so I am trying last chance here, to built it on my own. Thank you for reply. Mx.

Topic by Mirio46x    |  last reply

4 pins with unknown polarity, i want to charge a battery with it?

So I have 4 pins with unknown polarity, and a rechargeable battery with 2 pin with known polarity, and i got a multimeter. How am i going to solve this? I randomly did something and it worked, but it did not charge, but it could use the battery, but now its empty it cant anymore. layout used is --++ please help :)

Question by lhu    |  last reply

Do I need a diode? Answered

I am wiring 8x 5 mw lasers in parallel, powered by a 3.7v Li-Ion rechargeable battery. I was told that I would need a diode, specifically a 1n4001 diode to regulate polarity. I know what a diode does in theory (control the direction of electron flow), but I'm not 100% where in the circuit the diode needs to go. I'm assuming it goes between the positive battery lead and the output devices. Can someone clarify?

Question by h4xs4w    |  last reply

n channel jfet

Can someone show me how to hook up an n-channel jfet transistor? My power supply is +5volts. Where do I hook up the load. I know the gate has to be negative relitive to the source( the source and the drain can be used interchangably, right), but I only have a positive power supply. I want to use an n-channel jfet because it normall conduct, right?I found this website: I don't get it entireleyI am thiisss close to understanding how to use transistors!

Topic by guyfrom7up    |  last reply

why there is change in polarity in a bar magnet when it breaks?

A bar magnet when breaks does not attracts but repels from where it has broken ...   like [N-------S]   is a bar magnet on breaking it should be like  [ N---S} {N---S ] but it happens to be  [N----S} {S---N] ..  means there is "repulsion" between them WHY SO ?? (Pratically seen)

Question by aporak    |  last reply

Pump control - Uni or Bi polar stepper motor?

I am working on a robot that includes several annular gear pumps. We are using the MZR 2521, manual: (please see section 5.5) product page: In the description they say that you can run the pump as if it were a stepper motor. This seems like it could be done perfectly with an Arduino, but I was not sure whether to treat it like a Unipolar or Bipolar stepper motor as the setup for each is quite different. Does anyone have any thoughts as to which it might be? Thanks so much.

Question by Hammock Boy    |  last reply

I need help making a Polar Bear skin rug

I was wondering if anyone of you fine people could help me in the making of a Polar bear skin rug for my girlfriend for Christmas? Thanks

Topic by milonus    |  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 can you tell polarity of disposable camera flash and capacitor?

Wondering how to tell positive and neg on camera flash.. and the same for capacitor.. I see the capacitor has a greyish stripe down one side.. want to just wire strait from either flash or capacitor to restore/zap batteries back to life. Do you even need to get the polarity correct for this?

Question by burr0010    |  last reply

Lens Filter Question

I am fairly new to the DSLR world and I like the use of polarizer filters but is a polarizer filter still effective with a UV filter on top of it? I have it like this so I can easily rotate the polarizer filter

Question by physics_dude    |  last reply

electronic magnet that produces enough force to lift weight

you have an unlimited power source. now is it possible to create enough force at the right "degree" that would be repelled by the earth instead of attracted.. so like a floating magnet. but its strong enough to lift large objects..... like maybe a human?

Question by fireball9919    |  last reply

How can I get a filter whose color depends on the polarization angle?

Suppose you have a filter through which light linearly polarized at a 60` angle looks red, 120` looks green, and 180` looks blue. A mixture of 60` and 180` looks purple (red+blue). Unpolarized looks white (red+green+blue).Does someone make such a filter? Or one that only polarizes light in a narrow band of wavelengths and transmits other wavelengths unpolarized? Or can you think of a way to capture this information in a photo without specialized equipment or taking multiple pictures?

Question by NobodyInParticular    |  last reply

3d printer control software

I've just finished making a 3d printer, only there is one problem, I need some software to control it. I've built a polar 3d printer, where the extruder moves around a central axis and along the radius of that axis. In other words the extruder moves about a polar coordinate system. So, I am trying to find the polar form of a Bezier curve, where I can input a set of x,y coordinates and get a polar curve connecting them.

Topic by Gene Hacker    |  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 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 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.

Topic by Rich The Poor    |  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

Electromagnetism question Answered

Hi I just saw something weird, it's not an exercise or a problem but I still have a question :  Let's say we have 2 electromagnets of unequal strengths X and X+Y; between them we have a ferromagnetic bar  Let's say one has south polarity and the other one north if we change which one is stronger ex 1st is X,  2nd is X+Y than a moment after 1st is X+Y and  2nd is X the bar will have the polarity of the stronger one for a moment, right? ex for a moment the electromagnet with the south pole is stronger X + Y = the bar will become south pole than we return it to its normal strength X and make the north pole electromagnet stronger X+ Y= the bar will become north pole, right? How will such variations of the strength of the magnetic field on 1 side affect the entire device, will only the bar change its polarity and it will stop somewhere on the border of the second magnet or will the second electromagnet change it's polarity too if the first one's is very strong? (just wondering) If we fix a coil on the ferromagnetic bar will such variations in the magnetic polarities of the bar induce current in it and how much, as much as we used to produce the fields of both electromagnets or only for the field of the stronger one, or only the difference between 2? and the last question in the terms of relation between the strengths of both electromagnets (let's say in %) how much Y should be to change the polarity of the bar without affecting the polarity of the second electromagnet?  Thank you all in advance for your interest, assistance and time :)

Question by Elys    |  last reply

How do you figure out polarity for some salvaged circuit components, like resistors, etc? Answered

I took some resistors off a board and noticed that the board said positive at one lead but I didn't pay attention so how do I figure out which is which

Question by phillyj    |  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, 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

What type of capacitor are these? Answered

Hello . I just get some non-polarized capacitor .But What type of capacitor are these? Thanks!

Question by login721    |  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