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Capacitor? Answered

Can I make a capacitor out of plaster Paris/fix-it-all and washers ?

Question by wiccakingkamui    |  last reply


Hey, selling a massive box of Cap's.... see here if interested;;=151394654697#viTabs_0 Thanks!

Topic by 75lockwood  


How come capactors are used so much in electronics for exampel: what are those 2 capacitor doing?

Question by Balls of Kevlar    |  last reply


Hello my friends, i didnt post any instructable latly because i am in school and end is near.... but now i am working on few projects, and for one of them i need capacitor 1f 5.5 v. so my question is how long can this capacitor power the single white LED?

Question by tealk    |  last reply


So i'm trying to make a power supply, so for example if i make one with just capacitors (ill put a schematic if i can) and i hook it up to a device,Will it just discharge immediately or will the charge ask for a while?

Topic by minecraftpotato    |  last reply


I recently took apart an old stereo reciever that didnt work anymore. As always, I salvaged as much stuff as I could, and came across 2 huge capacitors. They are each about the size of a C- batery,and are rated at 50v, 6800 uF. I, of course, saved them, but now I cant think of anything to do with them!if anyone has any ideas, please let me know stat.

Topic by tigerdog330    |  last reply

Capacitor Value

Can someone identify the following MDC.05 +80%Z5U 20%1KVIs this a .05uF capacitor rated at 1000volts?

Question by TedD    |  last reply

What are capacitors for? Answered

What are they for I've seen them everywhere... are they used to hold power?  

Question by RelientOwl    |  last reply

capacitor control

I was just wondering if anyone knows any methods of controlling the energy discharge from a capacitor..

Topic by nuncoop    |  last reply

capacitor resistance

Why is it that as super capacitors capacitance goes up the internal resistance goes down? I'm looking for a tiny capacitor that can supply 0.3 volts20mA (I'm going to be powering flexinol, not an LED) for 1 second. I don't want the capacitor to be huge because I'm making a beam bot where size is a factor for charging time and because of it's physical size.

Topic by guyfrom7up    |  last reply

Capacitor Charging?

How do I charge a capacitor rated for 450v at 1150uf using 2 AAA batteries? I tried using a mini transformer but it takes a very long time. Is there a quicker solution? Thanks in advance, IndianHacker

Question by IndianHacker002    |  last reply

Capacitor Power

I want these so badly, and I live relatively close (about 300 miles away).|66%3A2|65%3A15|240%3A1318&_trksid=p3286.c0.m14You can make one heck of a capacitor bank, releasing almost half a megawatt in a split second.My only problems:I don't have 1600 dollars, crycry.These things are so large that if I were to line them up side by side (so that the thinnest parts create the overall thickness) it would be 25 feet long, 14 inches wide, and almost a yard tall. THE POWER BOGGLES THE MINDI'm so mad, if I was an adult I'd buy these in a heart beat... sigh... deal of a life time... I hope not...and best of all, they are PULSE CAPACITORSthoughts? comments?

Topic by guyfrom7up    |  last reply

Capacitor problem Answered

I needed a 2.2 and a 10 uf capacitor to make a metal detector, but the values printed on my capacitors are not less than 5. I want to find that if the values on the capacitors are in uf, nf or pf. And if they are none of them. 

Question by tanyutsharma    |  last reply

Replacing capacitors...?

I need to replace three 470 uF 25V caps but I was wondering if using 1000 uF 25V caps would work or not?

Question by gr33ko    |  last reply

Capacitor charger? Answered

Ok so im planning on building a portable coil/rail gun. But one issue is I cant quite find a circuit that would work best to drive a custom transformer. The charger I have now is a flyback driver that I used a wall adapter to power. I just need some advice and maybe schematics. Thanks, bud

Question by budhaztm    |  last reply

Capacitor charger

I want to build a fast simple capacitor charger with minimal components. i was going to builda dc to dc converter. but then came across this picture from here i am going to replace the switch with a 555 timer and transistor . does any body know if this circuit is any good or has any body built it

Topic by chrischavez    |  last reply

Charging a capacitor? Answered

Recently I've had an idea for a project that requires a relatively low voltage (5 to 30 volts) capacitor bank. However, that capacitor bank needs to be charged. While I do know you can easily just hook it up to power, I find that too simple, and lacking of safety, and knowing when it is fully charged. So, could anyone please enlighten me on how i can charge my cap. bank relatively slowly, with, say, an LED that lights up when charged (to avoid them blowing up in my face), and a kill switch/button that discharges the capacitor bank in the event of an overcharge. If anyone could provide an explanation or circuit diagram that would be great, thanks. BTW, the capacitors I was planning on using are or

Question by LiquidLightning    |  last reply

about capacitors

I understand that capacitors store electricity, but what controls them. what lets them discharge?

Topic by kendallickes    |  last reply

Microwave capacitors? Answered

Is it possible to put 25 microwave capacitors (2kv 1uF) in series and running 40kv through it without them failing?

Question by The MadScientist    |  last reply

Resistors and capacitors Answered

Can any one tell me how can we use and install resistors and capacitors? And how can we study the resistors and capacitors

Question by k.bipin    |  last reply

substituting capacitors

I was designing a board that uses a bunch of the same chip and all of the inputs require a capacitor. For example lets say I have 10 identical chips with identical setups. Instead of having individual capacitors for everything to ground (except for the outputs) can I combine all of the ceramic capacitors and use a couple of bigger electrolyctic capacitors? So lets say I can have 1 capacitor for all of the identical inputs instead of 10 smaller ceramic ones. But for stuff like timing do I need individual capacitors?

Topic by guyfrom7up    |  last reply

Shorting Capacitors? Answered

Hi Guys, Recently I found a person selling a power supply for $3 and I thought why not to buy it and salvage the components. I was wondering will it be safe to short the huge capacitors in the power supply? Thanks :)

Question by The Prickly Potato    |  last reply

for what this capacitor is ? Answered

I can't find 4.7pF ceramic capacitor

Question by Rendydevara    |  last reply

Is this a capacitor or a battery? Answered

In regards to my "battery free bike light".   I was told that a dynamo flashlight charges a capacitor.  Is this the case? Take a look, Thanks

Question by onrust    |  last reply

Help with capacitors

Hello everyone. I've seen this instrucable ( that uses a charged capacitor to light up a LED.I found this very interesting, so I started investigating what a capacitor is.So far so good and my questions are:- Can capacitors be used as replacements for batteries? I'm thinking specifically to light 1, 2 or 3 LEDs.- If so, how can I calculate the specs of a capacitors for a determined amount of LEDs.- Is it possible to calculate how much time the capacitors will keep the LEDs lit?- How can I determine if the capacitors have enough charge to light the LEDs?- Would you be kind enough to suggest a circuit to achieve any of these?Thank you.

Topic by transistor    |  last reply

Capacitor question?

I would like to know if I can hook up a capacitor to the incoming power being generated by my windmill so I can up my outage? I've been reading that you can use a capacitor bank to step it up. Thanks?

Question by swat420    |  last reply

Big Capacitors

I found a big capacitor in a floor cleaner...I think. It is a black cylinder with two leads off the end. In the floor cleaner, it was hooked up to a lot of stuff in a really important looking box that had a lot of wires flying everywhere. It looks sort of like the thing below, but a little smaller. So, really, there are two questions: 1. Is it a capacitor? 2. If it is, what can I do with it? Thank you!

Topic by DELETED_DELETED_basementhacker    |  last reply

Are these Capacitors Fried??

I think i blew out a cheap voice chance I have... can anyone verify that the capacitors I have circled are indeed blown... I've never looked before, and am not 100% sure the black isn't just a manufacturers marking. also, the caps are 20pF and 56pF and I need to replace them STAT... would Radio Shack's 100 pack capacitor grab bag have these numbers?

Topic by gschoppe    |  last reply

are these really capacitors?

Http://'m only asking because either the manufacture doesn't know what they're talking about or it's a battery with it's capactance measured in farads. The say rechargable capacitor. That's the only reason why I feel causious

Topic by guyfrom7up    |  last reply

capacitor help

Hey everyone i was wondering if someone could help me, I have a capacitor row (as shown below) and i was wondering what i could do to make it a shocker type thing? Any help would be greatly appreciated.

Topic by lakeside69    |  last reply

Capacitor Help

I am trying to build a lab power supply which I need to complete in order to continue an electronics course I am taking. The schematics require two 4400 uF capacitors, which for the life of me I cannot seem to find on any website or store. I was wondering if it is possible for me to use a slightly higher capacitor without causing electrical problems?

Topic by Sedgewick17    |  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

16Volt Capacitors

Hi everyone, I took apart an old Amateur Radio i had lying around and the boards have loads of parts, im wondering what i can use some of them for, most of the boards inside have lost of 16v capacitors and ive read instructables on making battery free torches etc, would these be of any use fpr these type of projects? Ideas welcome :) Cobs

Topic by Cobra_SFX    |  last reply

Giant Capacitor

Our microwaved died in my house so I took it apart for parts. I found a Giant Capacitor, its about 4in x 2in x 1in It has 3 Leads coming out of it and somthing that attaches to a panel, im guessing the ground. Does anyone have any idea what i could do with this let alone charge and have it release its energy all at once. Of course I have to clean it and am aware it could kill me at any time.

Topic by acer73    |  last reply

what is a capacitor battery/battery capacitor?

What are batt-caps, how do they work, and how would 1 be wired to a 1.5v battery? what are some specific names of different batt-caps?

Question by freenergyfuture    |  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

single lead capacitor

How can i make a single lead capacitor for this

Topic by taterkiller    |  last reply

Wiring Capacitors In series?

What are rules for wiring multiple capacitors in series? Especially when The voltages are different. If i wire two 80v's with a 200v what would my WV be?

Question by erncar    |  last reply

How to use capacitors?

So I just received my sample capacitors.  They are supposed to be 5 kv and a significant capacitance but I don't believe that they are. they are way too small.  I also want to know how exactly to use them, any ideas? 

Question by    |  last reply

Beer bottle capacitors? Answered

What is the average capacitance of a salt water beer bottle capacitor?

Question by The MadScientist    |  last reply

Tesla coil capacitor? Answered

Made a Lynden jar capacitor and my TC won't spark at the gap but I can hear my capacitor trying to work what do I do

Question by wiccakingkamui    |  last reply

How to charge this capacitor? Answered

I got this from a lightbulb. (three way)

Question by Xixfas    |  last reply

Capacitor Pin Extention

Good day everyone, I am sitting with a issue of changing a capacitor on a board but the factory default pins are to short to reach their holes. Is there a way to make them longer other then needing to get another new capacitor? I am using a 450V 150uf(M) capacitor. 

Topic by ChristopherC297    |  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

HV capacitor leakage? Answered

I have just built a high voltage glass capacitor for my Tesla coil at a 0.03uF 50KV rating and I have found that the leakage is quite high, the stored energy is almost completely gone in 15 seconds does anyone know how to resolve this?

Question by The MadScientist    |  last reply

What kind of capacitor is that?

So I've been trying to make a simple radio circuit based off of this schematic ( , but I don't know the type of capacitor that's labeled "C4, 220uF/ 25V" and looks like ---l]--- I tried searching for the types of capacitors on Google, but I cant get anything more specific than "polarized". Could anyone please drop some knowledge on what that is?

Topic by Actan    |  last reply

replace battery with capacitor

Hello, I have a old hair clipper.  It has a rechargeable battery in it, which does not charge very well. I opened up the clipper and it has a single battery. It reads d-2/3a700 mAh 2.4 v. What do I need to do to replace with a capacitor?  Like resistors and such. If I wanted to get it to charge quick.  And use it quick. thanks

Topic by gregdove    |  last reply

what type of capacitor is this ? Answered

Hello , i just bougth some capacitor from electronic store.In my country ,English is not the nature language ,so i dont know what is the name of this type of capacitor in English .they have number 104( 100nF)  and other is 105(1uF).And they dont have mask witch pin is  + or  -  pin.Thay mean they are Non polarized capacitor ??  Here is the image of them . Thanks ! p/s: sorry for my bad English.

Question by login721    |  last reply

Variable Capacitor Replacement?

Do you think it would be possible to substitute a variable resistor and a normal capacitor for a variable capacitor? The way I figure it is that a variable capacitor is supposed to adjust how fast said capacitor charges and discharges, wouldn't a variable resistor and a normal capacitor also function like this? I'm working on an idea for a small am radio, and looking to substitute these parts. Could it work? Thanks

Question by transistorguy    |  last reply

Why Is There A Capacitor In A Microwave? Answered

Why Is There A Capacitor In A Microwave? Also, does anyone know what kind of capacitor is it? Thanks :) I'm making a "What's Inside A Microwave" Instructable, And I'm interested what does it do, And I want to explain it...

Question by Yonatan24    |  last reply