Heat my home for free?

I want to build a HHO generator to supply a heat source for hydronic heating(under floor and/or baseboard). Use solar or wind to supply energy to run HHO generator and pump for heat system. Anyone else thought about this? As I see it, this could heat a home for free. Does anybody have any thoughts or suggestions on the subject?

Question by lordoftime   |  last reply


Home-made UPS? Answered

I recently acquired a very large 12V SLA battery and want to make a UPS for my computer. I think I have the basic idea, but I'm not entirely sure how I would go about this. I'm guessing I could use a relay to switch from the mains to battery, but then I would need a very large capacitor to run the equipment for a few milliseconds whilst it switches. I would need a separate transformer and regulator for the relay, and also an inverter for the battery, which I will probably buy as it looks like it would be too hard to make. Is this the right approach to it?

Question by andy70707   |  last reply


Home automation with time?

Hey everyone,  Not sure how many of you would have thought about it but there's a kickstarter project that reached it goal a while ago called 'wig wag'. Wig wag is more or less just home automation. I really like the idea, but hate the thought of paying hundreds of dollars for something that is definitely not worth that much.  Mainly what I'm most interested in doing is automate lights to turn on after a certain time due to a motion sensor. So when I walk into a bathroom at 1am, red LEDs will turn on (as they don't affect your eyes like white light does so you'll still be able to see).  There are some other things that could be cool, such as these lights not turning on if there is a certain amount of noise in the house (if I'm awake or maybe even if lights are on?). I'd be using LEDs I'd have some kind of 12v adapter rather than cracking into light switches in my wall. I'd also rather not buy a wifi powerpoint adaptor, (something like http://www.officeworks.com.au/retail/products/Technology/Power-Supplies/Electrical-Timers/BEF7C027AU?catargetid=1402860417&cadevice;=%7Bdevice%7D) I currently have a raspberry PI and and happy to use it for this but would probably prefer to buy an arduino but I have no experience with this. I have virtually no knowledge on coding so please forgive any ignorance and please give me your patience! It would also be lovely to have some sort of web server to be able to control it all.  Thanks everyone, your help is really appreciated. Pete

Question by pete54321   |  last reply


Is there a way to cultivating yeast at home for baking?

Was just wondering if there was a way of cultivating your own renewable supply of yeast at home from a fresh or dried starter?

Question by icecreamterror   |  last reply


Car Runs on Home-Brew Hydrogen

BBC News are running an item about a car running on home-produced hydrogen.UK company ITM Power has produced a plastic film they claim is suitable for home electrolysis of water to produce hydrogen. The hydrogen (they say) can be used in the home, to be burned for cooking or heating, or to power a car (they are simply burning it, but it could supply a hydrogen fuel cell).As we have mentioned elsewhere on this site, current sources of hydrogen are not "green" (95% of current H2 supplies are manufactured from fossil fuels), but ITM say that their system is green because you aren't stopping at a filling station, you're generating your own hydrogen from the energy resource of your choice (maybe your own solar cells or wind turbine).Others, however, have questioned the wisdom of storing tanks of hydrogen at home.Whatever the application, if this new material is all that they claim, it could be a major step towards a true hydrogen society.BBC StoryITM Power

Topic by Kiteman   |  last reply


Home Electronic Project, Can Use Some Help :)

Hey all I'm trying to hack together a few things to make a uninterrupted power supply unit. So far, I've got a 500W power inverter from 12V to 240V, and a car battery. Unfortunately, I also need a power supply capable of pumping enough amps into the inverter and battery to get the whole thing started. I've tried an old ATX power supply I had lying around (actually several :s and I figured if I can get at least a few amps out of it it'll power ONE computer at least) but as soon as the inverter is connected to the 12V line the power supply shuts down (even when it's not powering anything at all, just the inverter ATM). It's like some sort of safety mechanism, same thing happens if you short two wires across. I know there's nothing wrong with the inverter because I can plug it into a normal wall transformer (which fried as soon as I plugged something into it because the transformer only output 1A ), and it works fine powering a computer on the battery. Anyone know of a way of overriding this mechanism, or even better, a way of hacking together a cheap and nasty 240V -> 12V 50A power transformer? Maybe splicing two power supplies together, if it's possible? 'Shady

Topic by PacShady   |  last reply


Home/Lab made heating element?

I am trying to construct a heating element, preferably out of nichrome, for heating a small box (24 * 40 * 13 cc). The box is covered on all sides, so the heat dissipation from the box will be very low, as per estimate. I think a 12V supply would suffice for the nichrome wire. The only thing is, I need to maintain the box at an ambient temperature of about 38 degrees. Any thoughts on how I could go about constructing the heating element?

Question by Psyclops   |  last reply


Making an entire home portrait studio from scratch.

Ok I have decided today.... I am going to buld an entire home portrait studio From start to finish to take pictures of my little girls. Im going to build everything except the camera and tripod, and make it as cheap as possible while still keeping to the motto "simple stupid". Here is the list i have so far. soft box, reflector umbrella, back drop, backdrop stand,sitting box,power supply with switch (or switches havent decided yet), adjustable lights, light stands, and back drop holders. I will be posting the instructables as I go along. If anyone can think of anything else I may need please let me know.

Topic by scion6tc   |  last reply


Possibility of an 80 amp 12 volt power supply?

I'm just wondering about the possibility of me building one of these? I basically want to power a car amp inside a house. If its possible, how much money would I be looking at? How hard would it be to find the parts? And would I be better off paying $500 for a good home receiver, vs $200 for a good car amp plus whatever the cost of the power supply would be?

Topic by cvxdes   |  last reply


Getting started!

Hello everyone, I just found this site last night and lets just say that i didnt get to much sleep! A quick introduction about me. Im 24y old guy from sweden. I loved taking electronic stuff apart as a kid (not so much putting them back together) and i did some experementing in school but it soon faded. I then went on to become an electrician(house/construction installations) and have been working as one for 6 years now but never really went back into electronics. The last few years LED's has been getting big as the main lightsource in our homes but the comercial solutions aren't always satisfactory, hence my renewed interest in this. Only thing i've done outside of work is built some computers but never really modding. As if i didnt  have enough to do in my spare time i now wanna get into this, so i have a few questions on how to get started: - What basic tools do i need? Soldering kit, precision screwdrivers, multimeter......more? -What store is best for getting supplies/tools? Is it ebay or do you prefer a specific company? Any site that is better/worse to use living in sweden? Also should i stock up on basic components or just get what i need for my projects? -Is there any other communities that supplements this one? Any Swedish sites perhaps? -Anything else i should know before buying some stuff and starting? Right know im mostly focused on mods involving LED and lighting in general. Suggestions about that? Sorry if this is posted in the wrong section but i didnt really find any better place. I know this might not be as exciting as the other questions in here but all input is greatly appreciated!  TLDNR: What do i need to know/have to get started modding electronics? Cheers!

Topic by Allecc   |  last reply


how to make a simple swich with objects that can be found aroung a home? Answered

Im juslt looking for a way to connect a battery to a moter with a simple offordable swich that i could build using things found around home

Question by skeleton1102   |  last reply



Homes Protected from Raging Forest Fires

Every year we hear about countless homes being destroyed by forest fires. Unfortunately, the public isn’t aware that our current level of technology can readily address this problem. I have been examining a concept that has intrigued me over the past decade and which I call a “fire shield”. This shield functions by completely enveloping a private home and protecting it against encroaching forest fires. We’re talking about protection against a blazing fire storm generating high speed winds and flames in excess of 100 MPH. The shield would be a flexible structure that easily inflates like a balloon (needing perhaps three people for a day to erect) and forms a protective hemispherical, shell-like dome over the home (Fig-1). The structure would be impervious to penetration by high speed flames and their intense radiant heat, thereby keeping the enveloped home safe, cooled and protected. Each home would require a pre-fitted, customized buildup of a number of pre-built modular, balloon-like segments. They are manufactured and then assembled over the house only once, to get a customized tailored fit, then taken down and stored, and thereafter are ready to be deployed within a day’s advance notice of an encroaching forest fire. The Fire-Shield would be a modular, portable, inflated dome like those used for indoor tennis, which is prepared and custom-fitted to be later erected within a day. While typical inflated domes have their entire inner volume pressurized, our Fire-Shield will only require pressurizing a small volume contained between its double-walled structure that forms the dome as shown in Fig-1. The surface of its outer material uses NASA's radiatively reflective, aluminized Mylar to ward off the intense radiant heat of a fire storm. In addition this surface gets protected against the 100 – 150 MPH fire-winds, which are ready to impinge upon it, by injecting a high speed film of air (just like gas-turbine blades) produced by portable blowers. The actual heat-shield contains multiple, redundant pockets of cells directing the flow of air to both film-cool its surface and protect the shield against direct flame contact. Each major modular segment would contain its own portable, gasoline powered wind generator to supply the airflow. Depending upon home-size, several of these modules would be easily connected using Velcro plus redundant snaps and safety-stays. The shield gets attached over chimney tops and to pre-installed, grounded cement-posts, plus strategic hooks about the outside of the house. Special, inflated pillows are also strategically placed (between the shield and the house exterior) to facilitate the formation of a hemispherical shield that envelopes and protects our home against a high speed fire-storm. The Fire-Shield Design Concept The concept for a fire shield went through a gestation period of several decades as my career in thermo/fluids evolved. It started with the design of jet engine turbine cooling to thermal control of satellites, and finally to designing radiant heat barriers for cryogenics. These activities enabled receiving a score of patents as well. These activities inspired the concept for a rapidly deployable Fire-Shield to protect homes against a raging forest fire. The idea requires integrating several technologies ranging from inflatable commercial air domes to jet engine cooling to radiatively cooled spacecraft. Also included are flexible material coatings developed by NASA that radiatively reflects high temperature heat, making the deployable Fire-Shield a viable concept. Two key design principles are employed to protect both the heat shield and the home it envelopes. The first is shown in Fig-2 and uses a high speed film of air (faster than the anticipated fire-storm flame speeds of 100 – 150 MPH) that is locally directed to blow over the shield’s surface, cooling it and protecting it just like the metal turbine blades of jet-engines. The temperature of speeding flames impinging upon a jet engine’s metallic turbine blades is hot enough to easily melt them, yet the blades are protected by using this film cooling technology. The same technology will protect the heat-shield from meltdown when high speed flames of 100+ MPH attempt to impinge upon its surface. The second principle protects the shield against the intense radiant heat coming from a blazing forest fire where temperatures can exceed 2000 F. While this radiant heat does not physically touch the shield, as would a fire-storm’s flames, its presence is “felt” and is as deadly as the hot flames that would normally scrub over the shield without our film-cooling. We use a radiatively reflective, thermal coating barrier that repels this radiant heatload and protects the shield from melting. Such coatings were originally developed by NASA to protect satellites and spacecraft. The coating gets applied to the shield’s outer domed surface and will reflect better than 97% of all intensive radiant heatloads that are incident upon the dome’s surface. (Patent Pending; Original Concept Documented in 2006)  

Topic by RT-101 


I want to build an in-home speaker setup with ipod/phone jack? With the stuff I have have below, would that work?

I have a cpu power supply(specs below), 12 in Subwoofer, 1000watt amp, and misc. smaller speakers. With what I have can I make an in-home sound system? Plug in to the wall and i want to be able to connect an ipod, or phone,etc. I know there will be other parts needed, Im concerned with the parts I have working together first. Anything would be helpful. powersupply- input:100-120/200-240V~,7/4 A, 60/50Hz output-235W fuse rating-5a,250V

Question by tcarter6   |  last reply


How do I choose proper power supply for my ESC Answered

Hi, I am very new to this, I apologize if my question is too stupid :) I bought a brushless motor: https://www.amazon.com/gp/product/B01FTX5S0E (I can't find proper specifications, so I am not sure what is the voltage for this, but somewhere on the internets it was mentioned that this model needs 11.1Voltage, and 15-25A or 30A max. (not sure how to check if that's accurate, the motor is RS 2212-920kv) I also bought an ESC (I hope it's correct one...) https://www.amazon.com/gp/product/B016KF0E2W/ it says 30A on it. So seems legit to me. Usually they power this setup with batteries. but I want to use a power supply to power this from 220v outlet. I have some power supplies at home rated 2A, which I am sure is not enough. so I assume I need to get a 12v 30A power supply.  I am afraid though that my assumptions will get me to burn my ESC, which will cause another month of waiting for new one. Would really appreciate some help. What power supply do I need? how many volts my motor requires? should I provide 30A? does this kind of supplies even exist?  Thanks!

Question by AvetisZ   |  last reply


How Can I Reduce Current Without Dropping The Voltage?

Hello friends,                       i am making home automation with IR sensor , The problem is that the IR sensor sends random garbage values to arduino's serial monitor when connected to external power supply. The external power supply has output of 5v DC voltage and 2000mA current. The whole system worked perfectly when I take power from computer's USB port . The problem is how to reduce the current to 0 -500 mA of external power supply. thank you !

Topic by RakeshL1   |  last reply


Does anybody know of a Canadian source of buying KNO3? Answered

I have looked everywhere in my city and cannot find anywhere that sells stump remover or any other potassium nitrate product. If somebody says "look at lowes" they should be ashamed =PI have looked at Lowes, Home Hardware, Canadian Tire, Home Depot, and every other garden supply center around.

Question by FunkNattidelic   |  last reply


can anyone please provide me the complete stepwise guidelines for making a remote control for the home appliances?

I want to make a remote control for controlling my home appliances such as tube light , fan etc. so that i dont have to move from my place and i can switch them on/off sitting at one place .... i want detailed description on the circuit , materials required and the procedure f making the circuit... i also want a pictorial description of connecting the relay with the mains power supply...

Question by nfssaurabh   |  last reply


Can you take a look at the hardware for my first home built computer? Answered

I need someone to assure me that I've done this right before I order parts. I plan on playing a lot of graphics-heavy games and watching a lot of HD video. It would be nice if you could point out incompatibilities and possibly find cheaper hardware that works just as well or better. I want to run Windows 7 Home Premium on this. Case: http://www.newegg.com/Product/Product.aspx?Item=N82E16811226039&cm;_re=N82E16811121067-_-11-226-039-_-Product Motherboard: http://www.newegg.com/Product/Product.aspx?Item=N82E16813128421 Processor: http://www.newegg.com/Product/Product.aspx?Item=N82E16819115067&cm;_re=intel_core_i5-760-_-19-115-067-_-Product Power Supply: http://www.newegg.com/Product/Product.aspx?Item=N82E16817703027&cm;_re=silencer_mk_ii-_-17-703-027-_-Product RAM: http://www.newegg.com/Product/Product.aspx?Item=N82E16820104202&cm;_re=KHX1600c9d3b1k2-_-20-104-202-_-Product Hard Drive: http://www.newegg.com/Product/Product.aspx?Item=N82E16822136533&cm;_re=wd_caviar_black_1tb-_-22-136-533-_-Product Graphics Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16814150489&cm;_re=nvidia_geforce_9800_gt-_-14-150-489-_-Product Sound Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16829102034&cm;_re=pci_express_sound_blaster_x-fi_titanium-_-29-102-034-_-Product Optical Drive: http://www.newegg.com/Product/Product.aspx?Item=N82E16827136169&cm;_re=N82E16827136147-_-27-136-169-_-Product Wireless Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16833166051&cm;_re=N82E16833124069-_-33-166-051-_-Product

Question by Robotrekker   |  last reply


DTH satellite receiver problem

I have a DTH satellite receiver which has a burnt SMPS power supply (image attached). I replaced the burnt components but again when powered with 220V ac supply to test the output voltages the same components burnt again within a few seconds. I could not figure out what is the actual faulty part. If anyone has any suggestion please feel free to answer. My second problem is the satellite receiver board (image attached) has 6 pins for power connection but I could not figure out what voltage is to be applied to which pin. So I was unable to use a separate power supply for the receiver board. The part number can be seen from the image itself. Please look at the receiver board and help me if anyone has any idea about this board. I tried searching in google with the part number but could not find the same board. Please help me. Any suggestion is welcome. Satellite receiver: Hicway ali M3328C(10039)-11

Question by smandal13   |  last reply


LED Cube...Help?

So I made an LED cube. Forget programming I just wanted a cool home decoration. I plug it into a 5v supply and the LEDS aren't as bright as they would be individually hooked up. Can you help me solve this problem? I took out the resistors and it still isn't performing well. I have them in parallel. HELP!? Thanks

Question by fruitkid101   |  last reply


Problem using ESP8266-01 wifi module.

I want to make a home automation project using ESP8266-01, but the problem is that my module is not working correctly as I see the videos or articles, It's power light glowing very dim and also gives error while uploading the code(using Arduino IDE). Is that module is burned out or there is a problem with the power supply?Please help me .....

Question by AliR223   |  last reply


I need to build a wireless switch, I would like to be able to access the single on/off switch via my home network?

I'm looking to just control one on/off switch, using a low voltage to control 110v through a SSR. I would like to control up to eight relays but be able to increase or decrease the amount, depending on how many things I need to control. Software is not an issue, the hardware is were I'm having difficulties. I'm looking to keep this cheap, hopefully.  So in conclusion, a single on/off wirelessly controlled switch on my home network, that supplies low voltage to a SSR to control a 110v.  Thank you, Erik 

Question by eam1915   |  last reply


How do I use an old 19v laptop transformer for a laptop that needs 18.5v?

The title pretty much says it all, I have power 'brick' that is sitting unused in a drawer that has an output of 19v and 3.95A. The brick that came with the laptop I want to use this on has an output of 18.5v and 3.5A. I want to modify the older one so that it can be used at home, or as a backup, and the one that came with the laptop will continue as the primary supply when at work and on the go. Would it be as simple as adding a resistor(s), or am I going to need to figure out voltage regulators and capacitors? I kinda fall into the category of being experienced, but untrained...I can follow directions and do the work, but the more research I do, the more confused I get.

Question by vphreeze   |  last reply


Is a Wooden Enclosure for Electronics a Good Idea? Answered

I am in the process of converting my ATX power supply into a bench power supply. My PSU's standard case is made from 1mm steel with various ventilation holes, there is also a 120*120mm fan.  However, the circuit board is strangely positioned within the case and there isn't enough space for what I want to add.   I would like to take all of the electronics and rehouse them in a home-made wooden case. My question is; Is this a sensible thing to do? I plan to use 5mm pine stripwood to remake the box, but slightly bigger and better arranged. I would still fit the fan and drill plenty of ventilation holes.  Do I need to take any extra precautions if using wood, or is it just a really bad idea. Thanks in advance. 

Question by R055_28   |  last reply


How can I make a homebrew EEPROM programmer?

Hi everyone!  I have some EEPROMS I would like to burn (27C512, 27C256, 24C256).  I have a Parallax Propeller, a Z80, a 6502, and an Arduino Uno to help me make an EEPROM burner.  I know that EEPROM burners run $40+ commercially (even on EBAY!), so I would like to try building my own at home.  I have an abundant supply of 74XXXX chips at home, as well as a good supply of capacitors and resistors.   I don't have a Parallel Port on my computer, but I have a USB port as well as an RS232 to USB converter.  I'm running Windows XP and Ubuntu - Lucid Lynx 10.04, so if I need a specific OS to burn these EEPROMS, I have Windows and Linux. I need an EEPROM burner that could  erase/burn the 27CXXX EEPROMS/EPROMS/PROMS.  I know through using the Propeller that I can write to the 24C256 through the Propeller, but could someone please help me in building a homebrew EEPROM burner?

Question by prrgg14935   |  last reply


How do you electroplate, or plate, small jewelry pieces of copper or brass with sterling silver?

I make jewelry and would like to cover some small jewelry parts/ findings/ charms with sterling silver. The parts are made of copper and some of brass. I would need to do this in my home. If this is possible, how do I go about it? What supplies and equipment do I need? Thank you, Laurel Martin

Question by laurel1   |  last reply


Help Identifying unknown Transformer

Hello I got this transformer from an old ups, there are four wires on the primary side black, blue, green , yellow and two on the secondary red and blue. This transformer used to charge 12v 7.5ah battery also converts it back to 220V in backup mode. Tried testing its output and got this (Mains 220V) Black to ground Blue to mains-> 7.9v on secondary Green->5.5v Yellow->6.5v Connecting Blue and Green to mains and it was a shot circuit and blown my fuse. I want to use this for making a decent power supply 12v+ output, is this possible? I also saw this video https://www.youtube.com/watch?v=mc4GZM-kFUY&hd;=1 The guy is using his ups transformer for generating hv to power cfl using tip122, i am not sure how to do this using my transformer. I need to make use of this transformer somehow, otherwise its just eating dust at my home.

Topic by Clarkdale44   |  last reply


LED table lamp - 230v to 12V conversion which runs off mains power supply from socket

Right-o, hello everyone. I have come a bit unstuck in the planning phase of a lamp project and hope that one of you clever sparks on here can give me a bit of advice. I came across some quite large glass jars and though “wouldn’t it look good if I filled these full of water and put a light bulb inside”.  I searched for suitable underwater lights but the only ones that appear to be widespread are LED.  That’s fine I thought: long life and eco-friendly!   Now – it appears as if LED lights come in two voltage flavours.  The first seems to be able to run direct from mains supply as they appear to have in built transformers.  The second type comes in 12v and requires a separate transformer.  All the underwater lights I found fell into the latter category. Further research confirmed that the transformer has to be of a particular type - capable of delivering a constant un-fluctuating voltage supply, otherwise the LED bulb will burn out very quickly.  Now there are loads of transformers on sale for converting mains to 12v – however these transformers all appear to have been manufactured for placement behind walls or in roof spaces.  There also seems to be some suggestion that you have to purchase the “right type” of transformer to “match” the LED driver used in a given light.  I am now a little confused and I am uncertain whether I should proceed as the project I have in mind is to create a table lamp with a cable that plugs into the wall and that can be switched on and off with a switch installed on the cable.  All the LED transforms I have found appear to be for installation within roof spaces – and I am not certain they could be used with the particular bulb I have sourced anyway: Here is a link to the bulb I would like to use: http://www.amazon.co.uk/Aircraft-Aluminum-Waterproof-underwater-light/dp/B00E8B2F7S/ref=sr_1_31?ie=UTF8&qid;=1377529793&sr;=8-31&keywords;=underwater+bulb (my apologies If I am not supposed to post links to amazon – I couldn’t find a manufacturer’s website for this item) My questions are: (1) Will I have to buy a specific transformer to match the chipset of this LED lamp or will any transformer designed for use with LEDs be suitable (assuming that they convert 230v to 12v). (2) The lamp is rated at 10 watts.  Do I have to buy a transformer also rated at 10 watts or can I purchase one which is rated at say 30 watts.  What I’m trying to ascertain is: Do I have to match the wattage exactly or can I just use a transformer rated at 10 watts or above? (3) Can you get LED transformers that are designed for use in the home (i.e. not one that is intended to be installed in the roof space or behind a wall) e.g. is there such a thing as an LED transformer which you can plug directly into a mains socket? (4) Is there anything else I have failed to consider that I should take into account. Many thanks for any assistance.

Topic by rcgraham   |  last reply


My sweet computer

Ok, so i basically just set up my first pc. I actually built it from a dell dimension 4700. It now has a new motherboard which is much better. Heres the specs: Operating System: MS Windows XP Home 32-bit SP3 CPU: Intel Pentium 4 530 Prescott 90nm Technology Ram: 2.5GB Dual-Channel DDR2 @ 333MHz (5-5-5-15) Motherboard: ASUSTeK Computer INC. P5KPL-AM EPU (Socket 775) 25 °C Graphics: DELL E173FP @ 1024x768 Intel(R) G33/G31 Express Chipset Family Hard Drvie: 78GB Seagate ST380013AS (SATA) 28 °C Optical Driver: CD_ROM Drive Audio: VIA High Definition Audio Power Supply: The crappy 400W dell one from the dimension 4700. I really need to upgrade the power supply, cooling, hard drive, and maybe ram. Cooling especially, because i can overclock and i really want to. If i do a 5% OC, i stay at about 60 °C when playing games or stress testing. A bit more is pretty normal. Thats kinda hot though... So, thats why i want to upgrade the cooling. And it would help to upgrade the power supply a ton. And im going to need to with all the stuff i want to add. Anyway, heres some pics:

Topic by sci4me 


Arc Welding Advice?

My father-in-law just gave me this 295 amp arc welding rig (he's forbidden to use it anymore--pacemaker.) It's complete with mask, rods, etc. I've never welded before, and have a couple questions:-- Any good books or tutorials to recommend?-- I live in an older home (1930s), which has bus fuses and certainly can't supply 295 amps without burning out (or down.)Should I get a separate service installed for the garage? Is it expensive? I've looked on the power company website, and it's typical superficial information for the average customer...

Topic by gmoon   |  last reply


Get rid of batteries on the Fisher-price swing to DC input

We bought a new swing recently and has been consuming 4 C batteries every week. I am wondering if can hook it up to Wall transformer. Any ideas? I have some wall-wart at home that output 6-9v. Can I use them? I can convert the wall-warts as per the instructions here: https://www.instructables.com/id/wall-transformer-for-project-power-supply/ but do i need to change anything in the swing? and how to hook it up?Please advice ..Thanks

Topic by sulakhe   |  last reply


questions for rail gun?

I have a few questions about a rail gun project i'm working on... 1.) Where are some good places that i can buy parts for a decent railgun (i already know of some places like home depot (for the rails and casing) and radio shack (for some of the minor components)? 2.) Is there a better material (cost and in efficiency) than copper for the rail? (i heard aluminum is good, and i also heard silver is good but silver is expensive) 3.) what are good power supplies (something fairly mobile would do nicely, and i am not asking for specific requirements i am asking what other people have used as power supplies) if you commented on my last question, don't on this one please, i got your opinion. I would like an answer that is to the point please and not something that has to do with whether or not i should build a rail gun (i have gotten answers like that before which bugs me when i ask a question).

Question by Tobor 2.0   |  last reply


How to fix computer that won't turn on after power surge?

Recently we had some heavy rain and I had a few things blow out, including router, modem, desktop, and a few other things. But the question here is regarding the desktop that will not turn on after this storm and apparent power surge.  When I hit the power button, nothing happens. I bought a new power supply and it turns on again with only one problem. All the colors on my monitor display are very washed out and faded. I plugged the monitor into another working computer and it works fine so I know the problem isn't the monitor. The power supply unit that I purchased isn't exactly the same as the original since the original is a little old and hard to come by. So my question is what can I do to get my computer working like it used to be? The operating system is Windows Vista Home Premium and it is a Dell Studio XPS desktop. What do I need to replace to get my display working properly? If anyone can help me answer this it is much appreciated.

Question by Science102   |  last reply


Power LED Help

I'm looking to make some home lighting with LEDs, but I'm not sure how to regulate the current properly. I've really only used resistors up until now for led projects. I have a couple ATX pc power supplies, and I've used it to power an ebay led with no problems. I just touched the led directly to the 3.3v line and ground and it lit up fine. What I'm wondering is, is does the psu automatically adjust the current to what you need? Or is there something else I would need to worry about? (I figured it would be okay to power something off the 3.3V line if they were 3.7V leds, say several P4s)

Topic by opliko   |  last reply


emergency led or strobe lights

Does any one have a way to construct a L.E.D flashing warning light or maybe strobe light for emergency uses? I am a paramedic in a rural area and some times have to use my own vehicle to respond. Warning device needs to be relatively compact and low power draw. i just want to put red led's in my grill and maybe strobes in my head and tail lights. they make the high watt strobes(50w-80w) with the hide away grommets but they are expensive and the power supplies aint cheap. is there a reason i cant take apart a regular home strobe and wire it into a poxer inverter? thanks for any info steve

Topic by cruisermedic   |  last reply


My Arduino board affected by opening or closing any key to open any lamp in my house

i am an Amateur in electrical engineering  i learned a few thing  about micro controllers and i mad a project this project about light switch trigger by laser the project Component of 1- Home made Arduino board 2-home made relay module 3- home made voltage regulator 4-tow 5V 1A adapters 5- laser 6- photo resistor   the voltage regulator  take the power form the first adapter to supply 4.8V to the voltage regulate to out 4.8V to the laser and the laser pointed to the photo resistor and the adrduino board take the power from the second 5V adapter  looping on when the photo resistor value less than 750 then switch the relay module to high and delay the code for 10000 M Seconds and then switch the relay to low and end that is the project    BUT........? when i installed this project to the real live on stairs fluorescent lamp .... first it takes a while to trigger the relay switch  and the biggest problem i do not know why  when i open any near by switch to open or closing any of my hows lamp its trigger the relay on and then the rest of the code  continue normally not this only also when i insert any near by plug its look like some how connected to electricity   I Rely Do not know the problem where  and the schismatic for adrduino board , relay module and voltage regulator attached cold any body please help me

Topic by i_sadek   |  last reply


Will my Cold Cathode Computer Light work?

I just bought a Coolermaster ULTRA AURORA (DUAL) from a local store. On arriving home, i went to place it in my new HAF 932 case from Coolermaster. I have open slots and power supply for it but my video cards are to big to place it from the inside into the rear panel port. It has a on and off switch and a dimmer on it. Since i cant fit it in, i looked at bypassing the switch. the cord that plugs into the psu can fit in the switch or the inverter. I wanted to know if i can SAFELY bypass the switch. Go directly from the psu to the inverter to the bulbs is my plan. Would that be bad for anything? Coolermaster was of no help. Apparently, the model is 5 years discontinued no longer has manuals on file. They were less then helpful.

Question by trf   |  last reply


How to run (and power) 40 16' LED strips with a single controller?

I am working in a room with an exposed beam ceiling.  I am planning on running 16' strips of 12v RGB 5050 (150 LED) up each rafter.  So in total I will end up with around 40 strips.  Each strip is listed to consume ~36w.  Tons of info on the net about controlling and powering 2-4 strips at a time. But 40?  I'm having trouble drawing out how to power the strips (power supplies + amplifiers) at the same time being able to control them from a single controller.  (A simple generic controller that has selectable colors/ blinking/ etc)  Is is possible to control all these with a single RGB controller? I would love to get into a DMX setup. But all the DMX controllers I've seen only show controlling a grid of 300 LED's.  Is there anything remotely feasible for a home setup that could control 6000 LEDs?

Topic by mrlegoman   |  last reply


Tesla coil anyone with new design ideas?

I am in the early stages of building a new Tesla coil. After over 10 years without one I think it is time to add one to my collection again ;) As always I want to stick to to the classic design, meaning except for the HV supply all will be home made, including the capacitor. No no fancy electronics, just high voltage, a cap and a spark gap... However, classic must not always mean there is no room for improvement. Of course you can measure or calculate the frequencies for your primary and secondary coil before even starting to power it up - but where is the fun in that?? My last Tesla coil was driven by a 2KW transformer delivering 25.000 Volts. This time I go smaller for indoor use and will aim for a simple neon sign transformer with around 3000 volts and 20-30mA output. Reason for this that I plan to make an Instructable out of it if I find the time and would prefer to use power supplies that can be obtained in most countries without totally blowing the budget. I did some research on the net to see if there are any significant developments but the only things I could find are in relation to the spark gap or to use a conical primary coil. For the conical coil I could not even find any comparison to standard flat coil in the same system or a decent explanation why it is claimed to be so much better. My aim is to go a different way for the primary completely. Instead of using copper pipe in a standard winding pattern I want to try a quadfilar coil instead. My early tests on a small scale confirmed that a bifilar coil is better than a standard coil. For some weird reson the magnetic field reaches further and is stronger while at the same time there is less loss. So far bilifar coils are only used on some charging pads and "wireless power supplies" for TV sets. In most induction cooktops, where the benefits would be extra obvious, they are not used due to the higher cost factor of producing them. Big question here is: Has anyone experimented with bifilar or quadfilar coils in high voltage applications and is willing share some insight?

Question by Downunder35m 


Scottish Island Stays off Grid - replaces diesels with 95% Green resources.

The Scottish island of Eigg (pronounced "Egg") has never had mains electricity, and has had to rely in expensive diesel generators for the power they do use.Devices that require 24/7 supplies, such as fridges, have been an unknown luxury.Today, though, that all changes:A renewable energy supply giving the Isle of Eigg power 24-hours-a-day has come online for the first time.The £1.6m system for the island in the Small Isles between Skye and the Ardnamurchan peninsula uses a mix of hydro, wind and solar power.It has been designed to generate more than 95% of Eigg's annual energy demand and is backed up by a battery storage system and two diesel generators.Residents have previously relied on diesel generators and hydro schemes.The dream of green power has taken 10 years to realise. A total of 45 households, 20 businesses and six community buildings on the island are linked together by six miles of buried cable that forms a high voltage network.The whole project was organised by the community themselves - at the switch-on ceremony (in the local tea shop), the island's children gathered round a candle-lit map of the island and blew the candles out as the power came on.Before the switch-on:homes were powered by diesel, wind or hydro-generatorselectricity was unreliable and restricted to certain hourssome residents went without washing machines and vacuum cleanersthe noise from the generators could be heard for milesDiesel was delivered by boat but services sometimes cancelledBBC News storyBBC Magazine article, with comments.

Topic by Kiteman   |  last reply


Is this a good pcb design practically speaking? Answered

I designed this PCB in Diptrace and now i am going to etch it at home. This is my first PCB design. Can someone please tell me if this is a good and practical design? This is a design of a water level indicator based on a single NOT gate IC (HEF 4049). UPDATE: I redid the layout. Increased the trace width and attached the power to the IC. Please tell me if this is ok? Also please tell me is it must to have a power plane? UPDATE: 1) i went back to original layout and beefed up the tracks 2) Made the IC pads bigger. 3) Was able to reconfigure the layout to connect power without jumpers (this took up most of the time). 4) Did as Verence suggested and put text on the copper layer. Version number, date and name. 5) And finally added the positive for the supply voltage. UPDATE: Moved track from pin 7 of IC away from pin 8.

Question by Shariq92   |  last reply


If I wanted to make a homemade gel-cell or or AGM battery, what materials would I need?

I am thinking of building a homemade UPS (two actually) for use in my home. We have very bad power spikes and drops, and I have gone through 5 power strips in 4 months. My first thought was simply an off the shelf inverter and some lead acid (gel or AGM) batteries... but then I thought, why not go all out and make it all homemade? I know I can make an inverter myself, but have never attempted to cobble together a battery of any sort (unless you go back a couple decades and count the potato battery). I'm planning on making the UPS my first instructable, and would love to include (or have a second instructable on) the homemade battery as well. I'd want something that is deep cycle and which can support 1kw of continuous load pretty much 24/7 (assuming it is on the mains being recharged constantly).

Question by karossii   |  last reply


trickle charger for 14AH battery?

Hi, i am looking into making a 12v UPS for my home cctv system. i have two 12v 7AH batterys like the type used in fire and burglar alarm panels. my aim is to have a 240v input which gets converted to 12vdc and powers my dvr and cameras. the power supply of the dvr alone is 5 amps so i would need 1 5 amp output and then 16 lower amp outputs for the cameras but i guess this could just be done with fuses. now, here is the tricky part: in whilst also powering the dvr and cameras, i also need it to charge my two battery's wired in parallel so theres 14 ah of 12v battery's to charge (i may also add more at a later date). in the event of a power loss, a relay or some other switching device will switch power to all the devices to the battery so that its backed up. the only problem is that i am new to battery charging and don't fancy blowing them up. schematics, help suggestions all greatly appreciated. thank-you. - Luke

Question by ljarrald   |  last reply


How do I tune this?

I bought a passive subwoofer crossover the other day in Toronto at some crazy combination Home Hardware/Chinese ran semiconductor supply shop. It was simply bought as a pcb in a bag for $18, which I thought was a good deal for that much so I picked it up. It has a large inductor coil and a 188uF 50V capacitor mounted on it, along with a positive and negative terminal soldered on for input/output mono speaker connections. I did hook it up to try in line with my sony stereo and turned the default button on my EQ on to restore the original signal and it worked pretty good to block out most of the signals like I was looking for it to do. However even with the boost on my EQ at 30 and 60 hz, it's not coming through to my sub even like before I hooked the crossover up. I was wondering if that's because of the capacitor or not? The little peice of paper that came with it said it was a 120 hz passive crossover and that it was workable with 4 or 8 ohms. I'll post pics tommorow when I wake up as it is lateeeee. I appreciate if anyone can help me as I don't wanna take the capacitor off there to find out that it wasn't worth it.

Topic by Punkguyta 


What if i use multiple mosfets in paralell??? Answered

Today my dad brought me another matshushita photocopier. it was a huge one with 10stage output. It got broken some years ago and stayed at my dad's work. When i dismantled it, it took me about 7hours. it had about 1000screws and lots of wire notches and zip ties. The gears and the motors were absolutely incredible. But when i went deeper i found a big 2200uf 400v Phillips capacitor. Needless to say that my coil gun will be very happy. When i went to the power the supply the pcb was broken. but however i found a bunch of irfp450 and 2 irfp050. they are in good conditions. And a 220uf 450v capacitor. i am wondering that if i put several irfp450 in a driver, will it increase its power output or something else will. happen. I am planning to make a driver which will drive my 1000W transformer. It will step up from 32v to 330(using it's secondary as output. I got it from another matsushita photocopier that my dad brought ten years ago) it will be used to charge my capacitors in no time. Here is a small diagram which will help. i'm doing this like so because i don't have enough money to invest in home projects.

Question by ARJOON   |  last reply


Is it possible/can anyone explain how to transmit a USB signal through an "Ethernet over power" system.

OK, so we have seen "Ethernet over power" devices. In my home there is one with the "BT Vision" (its a UK thing). But I was wondering, does the input protocol of the signal in, allow you to send your own signal? I can understand if it can only send discreet digital signals, so analogue is probably out of the question. I'm sure you are all wondering what I mean. Well although my idea is for something completely different, involving a camera, and a mains powered reloading BB gun, I will appeal to the SPY cam enthusiasts, who are often very clever with lots of ingenuity. So you somehow manage to secrete a Spy-cam in somebodies stereo. How do you access the video? well there are 2 ways. one is to store is locally, this is limited by how bigger storage you can afford, and the limit of the device. The ones I know are normally limited at 4GB or so.  The other way is to use my suggested way, locate the AC input of the Stereo, implant the AC part of the "Ethernet over power" onto it, then plug the USB device into the Ethernet part.(probably with some kind of mods). Then at the computer in question, connect the output to your computer, there is bound to be a 5v supply inside the stereo, but if not, there are plenty of 5v regulators available. what does the community think?

Question by evildoctorbluetooth   |  last reply


help on designing a 12v UPS? Answered

We have a problem with kids coming into our garden, vandalising our plants, breaking into our shed etc. we have decided that installing a cctv system in our home is a good idea as even if it doesn't stop them coming in, it will be solid evidence to take to their parents. problem is, we have regular power cuts and i would like the cctv to be recording 24/7/365 (especially in the shed because that is where our bikes get stored) i have two 12v 7ah SLA batteries that i am donating to the project, iknow that they need 13.8v and around 500ma to charge. i need 16 camera outputs, and then a couple of spare outputs for aux devices (router to keep it connected to the internet, mics, infra red lamps etc) the dvr its self wants 12v 5 amps input so i think for that i will make another psu just for that with maybe 2 or 3 12v 7ah sla batteries. i have baisic electronics knowledge, have access to pcb printing facilities and can use eagle. any help at all would be amazing, the main things i need to know is: how to get 13.8v from 240v ac, how to power all the cameras from 240v ac and have a smooth switchover from mains to battery. thanks in advance - luke

Question by ljarrald1   |  last reply


please I need help with a PROPER wiring diagram for my project

Hello everyone,  its great to see a site like this exists, I am still picking my jaw up off the floor with some of what i would consider genius minds making some pretty cool stuff. well let me give you guys and gals a little info about my project, I am making a 250 watt aquarium light for my fish tank after walking into the fish store and getting price shock from the ones that had in stock.  I will be using several wavelengths rated at 350ma per 10 watt LED bead and I have 12 forward voltage per LED bead. My question is I want to use an old computer supply to power the light as I would like to stay within budget as best as possible and the chance to tinker with other electronics would be awesome for someone like me.  I am familiar with the proper way to wire up LEDs using resistors and the correct order to connect them. My only question is I want to avoid a series of LED only because I hear if one goes out the series goes out, but then I heard about a by-pass method to battle that. The other reason why I want to use a series and parallel is because I don't want to drill a million holes in my heat sink, rather I would want them all to meet at one end and join them together and insert into the female plug that the computer supply 12v line will plug into (after a little modding of course to the computer supply to carry this plug) also if I am going with 12FV led beads would using 25 of them in series and parallel be less efficient than if I got 32-36 forward V led beads??? or does that potential ultimately lay within the wiring of the entire aquarium light? I don't want to loose any potential of these LED which i realize is quite easy to do if everything isn't exactly right as far as resistor choices go etc. I would like to add a temp fail safe shut off in the wiring of the panel but am unsure where to exactly place that. If someone wouldn't mind taking the time to show the the proper wire diagram and be able to walk me through the wire diagram maybe via skype, I would truly appreciate that very much as its a huge passion of mine to learn but I am not in the position to be able to go to school because I have a disease that wont allow me to really leave the house. but I am wondering if there is anyone out there that can help me with my little hobby and project as I would like to use the knowledge learned in future projects and tinker around with some more electronics around the house. it would also be something nice to do when i'm home bored all the time. have a great day I look forward to meeting my fellow instructables. I am here to learn!!

Topic by LEDgrasshopper   |  last reply


(Arduino) automated macro-photography rail

Hi everyone, I would like to build an Arduino automated macro-photography rail (let's call it AAMR). I'm a decent software engineer and I want to learn electronics, so I'm looking for someone telling me I'm going in the right direction... The idea sounds simple, I want to : 1/ place the subject on the AAMR 2/ input the # of pictures needed to perform a "focus stacking" (https://en.wikipedia.org/?title=Focus_stacking) 3/ push the start button and make the AAMR loop n times through the following steps : - trigger the camera to take a picture of the subject - move the subject 1 millimetre toward the camera After a couple weeks reading and day-dreaming, here are my thoughts. I need : - to read more :) - a steeper motor and its driver (I own bipolar steppers and L298 / L293 IC) - to trigger the camera (Canon EOS 70d : remote cable is quite easy to make) - a potentiometer and 2* 7segment displays (input and display the # of pictures) - a start button - a reset button to make the rail come back at position Zero - two "end of course" buttons (not sure about the English terminology), just in case the motor wants to jump over the board - power (5v for the arduino and the logic, 12v for the motors) I. Arduino ---------- First things first, I plan to use an Arduino Uno during prototyping and replace it by a home made board in the final product. Uno has 14 Digital I/O Pins and 6 Analog Input Pins : - stepper => 6 Digital pins (3 ?? if using http://www.bristolwatch.com/L298N/L298N_arduino.htm) - 7segment led => 3 Digital pins if using shift registers (https://www.instructables.com/id/Different-methods-of-driving-7-Segment-LED-display/step5/null/) - start button => 1 Digital pin - reset button => 1 Digital pin - "end of course" buttons => 2 Digital pins - camera trigger => 1 Digital pin (to drive an opto isolator / solid state relay) - potentiometer => 1 Analog pin 14 Digital pins ! Uno should do the job, am I right ? (I know I could use Analog pins as Digital ones, but it seems I don't need it...) II. PSU ------- Next interrogation is about power supply : I don't want a battery powered device and my options are scarce : - ATX PSU supplies both 5 and 12v, but Arduino seems to like >5v, so ATX doesn't seem a good choice - home made PSU from an existing wall wart -> voltage divider to get ~7v and ~14v -> 7805/7812 voltage regulator (may need heatsinks and/or little fan) If I do the math : - Arduino : 50ma - Stepper motor : 700mA max - L298 : 70mA (quiescent current) - 2* 7Segment LED (multiplexed) : 2 * 80mA (estimated) - Shift registers IC (SN74HC595N) : 1ma (optional : Hex inverter 74LS04 : ?? mA) Total : around 980mA... Am I doing right ? I have tons of questions left (Hex inverter, filter capacitors, motor noise reduction, solid state relays...), but it's a good start :) Sorry for the long post, and thanks in advance for your answers ! D

Topic by djezzz   |  last reply