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Can adults enter in the contest or is this just for students?

Just wondering if adults can enter the contest or if this site is just for students k - university?

Topic by AshleeN15    |  last reply


Multiple entries in Contest

Hi I've been visiting this website since I started learning electronics. I saw an open contest for members, so I signed up. This will be my first instructable and contest, is it okay to submit one (1) entry to multiple categories as long as it fits the category?

Question by jiann.wong96    |  last reply


Recycling a printer's laser

My laser printer stopped working.I opened it and took the useful parts out (motherboard, cables, ...). I checked some project ideas and got really interested in connecting my raspberry pi and the LSU (laser scanning unit) to experiment with it.Since I think it is not gonna be easy, do anyone know how to connect a laser to a raspberry?Here are the specs of the LSU:https://www.manualslib.com/manual/1182945/Samsung-...The laser's board is a 94v0 / 1794v0, it has a 5 pins output. But I can unsolder it from there to have a 3 pins led.(I'm sorry I'm not good at this ^^" trying to learn)

Question by Bombardier0    |  last reply


Wiring a usb outlet and ceiling fan on the same circuit

In my daughter's house (in South Carolina) her outlets and lights are on the same 15 amp circuit. I installed an outlet with built-in usb ports. She has her Fire Stick plugged into one of the usb ports. Her ceiling fan is controlled by a wall switch knob with OFF, MAX, HI, MED, LOW options. When she turns the ceiling fan from one option to another, the Fire Stick cycles off and then back on. Any suggestions? Thank you.

Question by lindabluffton    |  last reply


HCl obtention from bleach and acetic acid (vinegar).

I have always been curious to know if it is possible to obtain hydrochloric acid (HCl) from chlorine-based bleach and acetic acid (vinegar). I found a lot of answers saying that it was impossible and dangerous because you wouldn't obtain HCl; instead, you would get chlorine gas, which is a very dangerous fume that can cost your life. However, I found an answer saying that it was possible to synthesize it, but not directly from bleach. First, you have to mix equal quantities of bleach and acetic acid to obtain hypochlorous acid (HClO) and then you have to add a transition metal oxide (iron oxide, copper oxide, etc.) to get HCl and oxygen gas.  Filled with curiosity and keeping in mind that safety is the priority, I decided to try it out by mixing equal portions of bleach (NaOCl) and acetic acid (C2H4O2), obtaining an aqueous solution of hypochlorous acid (HClO) and sodium acetate (C2H3NaO2).  NaClO + C2H4O2—> HClO + C2H3NaO2 Then, I added copper oxide (rusty pennies) since I know that copper by itself reacts very slowly with HCl, so I could leave it there until the copper oxide had completely reacted with the HClO (leaving clean pennies).  Little but numerous bubbles started to come out which I thought to be the oxygen gas leaving the hypochlorous acid. I waited there until there were no more bubbles coming out which meant that the reaction had finished. To prove that it was HCl, I decided to add Aluminium foil and see if it reacted accordingly. However, nothing happened, so I tried the whole process of mixing bleach and vinegar again but when I got to the part of adding the metal oxide, I did not add copper oxide. Instead, I left it outside in the sun to react since I know that ultraviolet radiation causes fast disproportionation, forming HCl and oxygen gas.   HClO —> HCl + O2 After all the bubbles had finished coming out, I added Aluminium foil to prove that it was HCl. However, noting happened, and again, I obtained the same product as the last time.  I immediately stated to think of possible products that I could have obtained and the reasons why my reaction hadn't worked properly. It was then when I remembered that in the very first reaction (the one of the vinegar and the bleach) I had obtained a side product that I had completely forgotten about; sodium acetate (C2H3NaO2). And I suspect that this side product could have affected the whole process.  And that is my question; was it really the sodium acetate that one that affected the experiment or could have it been something else?

Topic by Joseluismi    |  last reply


Yet another unidentified tool

Hi guys,Can anyone tell me what this tool would have been used for?The fine wire is spring loaded.I was thinking perhaps a pricker for an old gas or kerosene lamp light to clear the aperture, or maybe a paint gun.Seems an over complicated device if it is what it was used for, but i guess it protects the wire by retracting it.

Question by AussieAlf    |  last reply


Peltier dehumidifier Answered

Hello. I'm experimenting with peltier dehumidifier. First I know its least efficient dehumidifier but I have one and I'm trying to experiment with it to increase efficiency. We have many smart people here, maybe you guys can help me to understand one thing. On peltier dehumidifier air is pulled through cold side in to the hot side and warm "less humid" air coming our from other side. Why not to pull hot air from the hot side and reroute it to cold sink because that would create bigger temperature difference on the cold side and would increase condensation and warmer air has more moisture as well. Please correct me if I'm wrong because I dont understand why these dehumidifiers are made this way. Thank you

Question by TeddyWeddy    |  last reply


Adding a recent, published Instructable to a contest

Howdy,I've just released a 'ible and want to add it to one of the contests. For the life of me I can't work out how to do it! If anyone can please let me know that would be great. I did try and to add the comp to the new 'ible when I published it but for some strange reason I couldn't publish it with a comp attached!Thanks all

Question by lonesoulsurfer    |  last reply


Help Hacking A Music-Playing Clock

Hi everybody. I am interested in hacking/reprogramming this composer clock. As it is now, it plays a different clip of a song by each of the 12 composers on the clock when the clock hits the hour that corresponds to the picture of the composer (for instance, Mozart’s face on the 1 place of the clock, it will play a clip of his music when the hands hit 1 o’clock on the hour). Here is how it works already. • There are the 12 clips of music recorded on a board. They are heavily compressed (small files, I guess) and pretty gritty quality, but are definitely audio clips of recordings and not midi or synthesized versions. • They play back in order, triggered by a mechanical trigger that fires whenever the minute hand passes 12. • There is a button on the back that will allow you to manually advance the tracks (I think does the same thing as the clock hand trigger), you can use this to help make sure the songs line up with the correct composer when you reset the clock (I think…might be wrong about some of these details. • There is a little photo sensor at the top of the 12noon position on the clock facing out (see pic). At first I thought this was the trigger, that when the minute hand passed over it, it would block the light and that would be the trigger for the next song. However, that’s not the case, and what this photosensor actually does is control the volume of the clips' playback. That way, if you have the audio function on, it will only be audible when the lights are on. It will play when the lights are off, but is so quiet you can’t hear it. A very clever system!Here’s what I want: I want to hack this clock as a present to my wife who is a composer, with the faces of other, female/femme composers and performers that she likes. I want it to play clips of songs by those new composers when their particular hour comes around. -So I want the same exact functionality of the system, just change the songs it plays.What I have done so far: • I’ve exposed the board and other components of the playback system (see pics). I had to pry through the plastic casing on the back since there wasn’t away to get to it without destroying the face of the clock, which I already converted to the new composers. • I tried to identify the components and learn about how the system works and took pics (below). • I did a cursory search for the pcb board with the markings “DLT356 REV:S1” for info but haven’t had much luck.What I know: • I’m ok with soldering and construction, I know a bit of C, Arduino, Processing and am really interested in learning more about physical computing.What I need to know: • Can I access the microprocessor with the audio clips on it and figure out some way to swap them out with other clips? I like all the other functions of this system (the minute hand trigger, the photosensor volume control, the override button). • If not and if I need to build a new playback system, and suggestions for chips and programming language/mechanism to get started with? • Any leads would be greatly appreciated!Thank you!J

Question by redshouldrd    |  last reply


Basic leather crafting question

I am brand new to leather crafting and just ordered a vintage stamp with 3 other tools. I think i just broke the stamp. It is flat with a hole on the back. I used a hammer on the stamp by itself and the hole looks like the ridge around it is broken. Was I supposed to put something in the hole before hammering?

Question by Jlady711    |  last reply


Arduino code. Air-con temp controller. Please help if you can!

The hardware is an R3 with a custom LDR interface for reading the mode of the air con, and relay interface for changing modes. There are 2 digital probes, one for temp control and the other just for display. This was made for climate control of a small room using a portable air-con. The controller switches between 3 modes; Heat, Cool and Fan. What we need is for it to turn the fan on when SP is reached. When starting from a power failure it will switch to fan mode if the temp is within the range of SP+-1. This makes it look like it's working correctly but after that it loops between hot and cold; the fan is never turned on again, although the readout on the controller reflects the temp is OK, so the fan mode should be activated. I have attached the coding as well as a print out from the serial monitor showing the errors on the controller. The guy who wrote this for me is unable to figure this out.Would appreciate any help!

Question by LiamS68    |  last reply


POWER TOOLS

I was just wondering what are good places to buy power tools from, thanks.

Topic by TREX ZoaR0K    |  last reply


Is it possible to make HCl with Bleach?

Is it possible to make HCl with Bleach? As in could you use any conversions (Toxic and dangerous should be included for informational purposes) to mix the bleach with some substace leading to it? Because bleach is Sodium hypochlorite (NaOCl) and it does have a Cl.

Question by a_traceur    |  last reply


Verify my account? Answered

A little box keeps popping up saying "Hey DCA, you still need to verify your account".  I do as it says and a box pops up with an old but still active email address, I send it but it never shows in my mailbox. Nothing wrong with the address, I still get other mails.  What's up? Also, I don't see anyplace to ask a question of the Instructable staff. Thanks,  Dave

Question by DCA    |  last reply


can you help me identify this alternator? Answered

I just got this alternator from my grandpa and am going to use it in a generator I'm working on but I Don't know what kind it is. He told me its a one wire but it has some prongs on the top. Any information is helpful and help is greatly appreciated. Thanks       Harry

Question by harry88    |  last reply


The dirty little secrets about switching to LED lights

Some years ago we were told to invest in more energy efficient lights for our homes.Incandescent was using too much power, so CFL's, Compact Flouroscent Lights were the ting to buy.Much higher price than the normal lightbulb but hey we save a lot of money in the long run.No one liked the long warm up time to get full brightness...And even less people actually got the claimed lifespan out of them.Add the recycling costs and hazardous waste created and the costs of using CFL's is actually much higher than standard light bulbs.The only savings were for the power companies.LED lights had a slow start but once mass production started price went downhill fast.What started in the EU was made compulsory in other countries soon after: A ban on incandescent light bulbs.Thee are only a few exceptions left like bulbs for your oven as LED's won't cope with the temps here.So why was the ban necessary?An incandescent light bulb was available for often under a buck, so having some spares at home was no issue at all.Making people switch to LED lights that often cost 20 times the amount of an old standard light is impossible.Biggest incentive of course was the short boom to the local economy as the initial batches were all sold as high quality items.The scam started to evolve when it became clear that even with LED lights the overall savings hugely depends on how you use your lights.As a factor on your electricity bill the lights are usually at the bottom of the list.Things like heaters, airconditioners, fridges, freezers and of course TV's are the main users of electricity in many houses.During the winter times this changes as we need more light but still the impact is not as high as you might think.What did change though was the behaviour.Since we now save so much energy we don't really worry as much if the light is kept on for no good reasons.Again, the main savings are with the electricity providers.I won't deny though that a house with 100 60W incandescent lighs will have some benfit on the electricity when switching to 8 or 10W LED lights....Lifespan...Like so many others I have some stories about incandescent lights...For example the one had in the basement when I was a kid.Often on for several hours, sometimes just for a few seconds to quickly grab something.But it still worked fine when I was an adut and never had to be replaced.Or the house that destroyed lights on a regular base thanks to power surges from the nearby industrial areas.LED light were meant to make the difference here.Put them in and never worry about replacing.10.000 or more hours before the LED's fail...Nice claims but never fully true.10.000 is a bit over a year of constant use.Most people won't just leave the lights on for the entire year.So you would expect that a good LED light will work just fine for at least 5 years, under normal conditions close to 10 maybe.There is several problems with this claim - none of them are explained in the warranty leaflet and nothing was explained by your government when you were forced onto LED light.Electronics even as simple as a resistor come with a limited warranty.Some will remember the disaster when bad capacitors turned thausands of flat screen TV's into flashing lightbulbs.The parts used to make the lights can be a year old already before they are soldered together.Then there is time for shipping, storage, distribution.Sadly not all countries require to print the manufacturing date on the packing or LED light.Means that by the time you put a new LED light bulb into use it might be two years old already.Similar for the claim that the light won't emit heat.Sure the LED light itself is cold but the heatsink the LED's are mounted on is far from it, same for the often underrated electronics inside.In return the electronics suffer from the excessive heat, espcially if mounted in lamps not designed for them.Which makes the entire replacement a scam for most people.It is not uncommon that a LED light fails within a few months.If you are lucky to have kept the invoice for it you might be able to get a new one from your store.Now I replaced 20 lights when I moved in here.Only the first three that failed got replaced, after that the shop claimed I would misuse the warranty.I inspected them and it was not easy to get inside.The switching IC used should have had a heatsink according to the datasheet, without it the circuit board got toasted until the IC finally cracked.Without a sufficient heatsink the IC was only rated for a max of 5W while the light had a LED assembly of 15W...I kept doing these destructive examinations whenever a LED light fails.So far they ALL had sure signs of overheating, either for the switching IC or the tiny transformer.No one really bothers though to keep track of the hours a light was actually used and with that we just keep buying new ones with no worries in the world.Recycling....An incandescent light was never really worth much to begin with, so the final grave was the normal rubbish bin.CFL's required proper disposal due to the hazardous materials in the tubes.A comparison between the amount of sold lights and what ended up in recycling centers reveiled that the ,ajority of them ended in landfill because people tossed them in the normal rubbish.The long term impact of those chemicals on the enviroment will be hidden under fresh grass by then.LED's claimed to be the way out as they were meant to be fully recycleable.What really happend with our collected recycling bins was clear when China stopped taking it.....Means all the still usefull materials in those expensice lights again just go into landfill.A total waste on so many levels.So what is the real cost then?Electricity prices are only going up, so saving Watts wherever possible is a good thing.But ask yourself:How much energy and ressources were required to produce an incandescent light bulb?How much more is required to produce a LED light?We are told to focus on our electricity bill alone without considering the overall costs.Since we already pay the extra of making them we tend to forget what happens once they fail.More waste, more landfill, no recycling of the lights at all.But does it prevent your next blackout when the grid is at max capacity? Nope...Keeping your big airconditioner off for a hot day or two would save more electricity for the year than changing from incandescent lights to LED's ;) Does that mean we get way more efficient airconditioners? Nope...Where in developing countries cheap and highly efficient compressors are used we invented inverter technology ROFLMakes no difference at all on max power to have an inverter.The only real difference is that it runs slower at lower capacity while a normal airconditioner turns the compressor on and off.Forcing the use of highly efficient compressor technologies and replacing our old style systems would have made a real difference on the overall electricity use.We "save" electricity with LED lights and only turn them on if we really need them.Still the 5 or 7kW airconditioner runs all summer long and in the winter it heats the house and uses even more electricity.Makes you wonder, doesn't it? ;)

Topic by Downunder35m    |  last reply


Are catalytic converters poisonous?

I've been looking around and it seems like most catalytic converters have palladium in them. I think palladium is mostly inert but palladium salts are highly toxic. I would like to open up a catalytic converter and use the substrate to make a thermoacoustic engine stack. So do you know if it would be poisonous to me to open a catalytic converter? Thanks!

Question by snotty    |  last reply


External aquarium heater with digital control

I lost about 300 fish just a few days ago when my tank heater decided to stay on when it failed.(examination showed the theromstat contacts were fused together)So far I never worried about failing heaters as so far they just wouldn't heat anymore once the failed.This time I lost about $400 in living creatures and 2 years of breeding.Guess that is the punishment for being away for a few days - a bit over 50°C in your tank...Normal tank heater come in the submersible form or with the clear instruction NOT to submerge them abvoe a certain line - usually under the rubber capEither way they all love to fail within a few years if you are lucky, otherwise sooner.The one thing I always hated is that you need to find ways to hide them in your tank, in some cases you even need to a heat shield to protect sensitve critters in your tank.I though that there should be a cheap and easy way to eliminate most of the annoying factors....Simple, digital temperature controller....You find digital thermostats for your fridge and freezer for around $30-100 bucks, depending on the brand and features.Downside is they all activate the output once the temperature gets too hot.For under $10 you can get universal thermostat controllers- just a tiny white box with the display, two buttons and a few wires...Won't place a link but with the above you should find them on Ebay and Amazon for as said under $10.These can be set with the min temp being above the max temp - this effectively reverts the output state ;)Looks a bit weird when setting the temps this way but after that the power on the output is alive once the temp is BELOW of the set temp.And you can set the differential as low as 0.1°C if you like, but 2-3°C are fine for most tanks.Abandoning the internal heater thermostat....As the number one cause of failure apart from water getting inside we should not use the internal thermostat anymore now.To do this without messing around the temp is simply dialed way above what you will need for your tank.E.G.: If you want 24°C in your tank over the digital controller than the heater thermostat is cranked to 27° or higher.The on-off will be handled through the power our new digital controller provides.Sealing a heater....You should not have to do this but an awful lot of heaters simply fail because water makes it inside somehow.I use a bead of UV curing resin or UV curing epoxy glue for the first stage.The glass won't really expand, so the rubber from the cap won't expand much either.All we do is to add another layer of sealing protection.That stuff however is not always fully qualified for being suberged or just in contact with water a lot.So we add another bead of aquarium grade silicone on top.This also protects our tank from any harful chemicals the UV glue might otherwise release over time.Going external...With an external filter pump it just does not seem to make much sense to have a heater insde the tank.For some reason those filter manufactureres though about almost anything, including build in UV sterilisation - but not a heater...Using a bit of 5mm PVC drain pipe, two end caps and some hose fittings for your aquarium hoses we are set again.A bit of stainless steel wire from the gardeing section of hardware store helps too - the soft, flexible kind, not the really stiff and hard wire please!Design of the external heater:In one end cap you want to drill a hole of the same diameter as your heater tube, a mm bigger won't hurt too much but don't make so small that you need brute force to get the heater through the hole.Seal the inside and outside of the cap with silicone.If you want the heater to be replaced easily in case it does fail again (which it should not!), then you a pipe with a screw fitting and a screw on cap.Keep the assembly steady and secured while the (aquarium grade!) silicone cures - if in doubt let it cure for few more days.The lenght of the pipe should be so that there is enough space left in the bottom so the heater will have about 6cm until it would touch the other end cap.The pipe connections can be for one on the other end cap if you mount the pipe somehwere, otherwise both connectors should on the side of the pump and as close to the caps as feasable.Again, seal the inside and outside of these connections with silicone and let it cure.It helps if the fittings are of the screw in type with a backing nut.Downsides of having an external heater...You need to clean it out when you clean your filter, an added few minutes.If the heater thermostat is set too high and your pump is not running the water in the pipe and hoses will rise to the set temperature of the heater.For a medium sized tank that is no problem, for really small tanks it should be considered though - set the thermostat of the the heater not to the max if you think you might forget the water circulation one day ;)Upsides of having an external heater...The biggest benefit of having and external heater with a digital temperature controller is the lifespan.I used a dirst cheap 400W tube heater like this for over 6 years until finally the actually heating element failed.With the nicely illuminated temp display the times of checking the sticker on the tank or trying to read this tiny floating thermomoter are over as well.Possible upgrade options if you know how to solder or at least know how to correctly wire a relay...With an external tube comes the option to include a UV sterlisation lamp on the other end.The tube will be accordingly longer but a submersible lamp only costs a fraction of these ready made solutions that you still need to attach your your hoses somehow - and they are often quite big...Apart from that there is the option to modify a digital fridge thermostat (about $20-100 bucks) like the STL-1000.As most of them can't be re-programmed for other than cooling use and only have a single output for the compressor the internal relay needs to be replaced.Just select one that somehow fits inside once the original is removed and wire the NC and common output for your heater.Not in mood to fiddle with a controller and solder? No problem either!Just wire another relay to the output.Means the power that the controller switches on it will then switch your additional relay on.This gives you the option to use the proper contacts again to turn your heater on.Using a normal fridge controller this way however requires thinking the wrong way around for the temps.Remember!! : The frige controller "turns on" when the temp goes ABOVE a set temperature!!If you use it like this and connect your heater directly it means it will only turn off once the temp is BELOW the set temp and it will never again go below, only up and up and up....The added or exchanged relay however gives us the option to reverse this to some extent.You set the controller to the MAX temp that you want in your tank.Let's say 24°C , by default this gives a 3°C hystersis, meaning depening on the programming of the controller it will turn on at 27° or close to it - keep that in mind add realise that it means your 24° might need to be set to 21° so the temp won't go over 24° in your tank.Ok, got it, but what exactly happens now and why does it work?When the controller reads below the set temp, like when setting up a new tank with cold water from the tap, it won't provide mains power on the compressor output.It knows the "fridge" is fine right now.Our added relay will be off for the same reason, however we connected our mians power to the common contact of the new relay, the heater on the NC (normally closed contact) and from there back to neutral.Means our heater will get power when the temp controller in the OFF-state.Now the temp start to go up in your tank and sooner or later it will reach the set temp you adjusted the controller to.Suddelny the controller sees a risk for your food in the fridge to go bad and decides to turn the compressor back on to cool it down.As we added our relay it means it will turn on as well.Our NC, normally closed contact, opens and the heater turns off.From ther is just continues within the range of about 3°C....You added digital temp display to your nice fish tank, don't have to worry anymore about your heater prematurely failing and if you like:Some controller offer an alarm output.This can be used with an added relay the same way as before and would then warm you if you heater burnt out and the temp in your tank goes too low.Why so "complicated" if there is microcontrollers?Anyone can use some Arduino and do the same with ease - if anyone can program what it is required.However, even our average Joe with no electronic skills can to the above mods within a few hours excluding the curing time for the silicone.Back to the basics, and after all we already have a microcontroller inside out firdge controller ;)And as said, if in doubt then even a $10 one will do the trick without any mods to it.What about that stainless steel wire?? Don't tell me I wasted 5 bucks for nothing!You did not...Long heaters or UV lamps certainly benefit from it.But even a smaller one is much more stable inside the pipe if you create a simple wire cage for it.The stuff usually comes in a rolled up form of a 10 or 20 meters.With that it is easy to make some loop with the heater ube in the center.Just make a wrap around the pipe with enough left either end to form a ring or spiral that fits inside the pipe.There is not much spring action happening with this wire, so the loops can be quite big and you just push them inside inside while decreasing the diameter until they slide in.If you have a 3D priter you also just print a ring with a hole for the heater and some spokes to cneter it in the pipe.What about heat transfer and even temps in my tank?With the usual in tank setup you have to ensure anyway that the heater is in the waterflow.Otherwise one side of the tank warms up more than the other.With the heater being in the flow of the external pump directly we pump in warmer water and suck out the colder water the other end.Results in a more stable and even overall temperature especially on long tanks.Enjoy!

Topic by Downunder35m  


PC is stuck on Automatic Repair anyone ?

Tried everything

Question by jimhardingsr    |  last reply


How do you build a home made wood burning Sauna heater?

1 Nov 2011.    I am stuck on a Firebase in Afghanistan and winter is approaching fast. So i was thinking that building a sauna would be a cool project.  The wood shack isn't that hard, but how to build the stove/ heater/ thing? So, Any ideas?

Question by EcoExpatMike    |  last reply


Spot-welding Li-ion packs - charged or discharged?

I'm making a large 18650 pack for my onewheel-like hoverboard build. It's my first attempt at spot-welding (DIY spot welder powered with a MOT, scary beast can melt entire M8 nuts on longest impulse time), so I'm afraid I'll mess it up. I was wondering... is it safer/more convenient to work on charged or discharged cells? Does it make any difference at all?

Question by MichałK83    |  last reply


Making a pillow with pressure sensors and a keychain connected with bluetooth

Hello, I want to have information on the materials and the process to make a pillow with a pressure sensor that is connected with a key ring and warns when the child is sitting on the seat and the key ring moves away.

Topic by GiovanniA34  


NET GUN

I am VERY INTERESTED in Buying A NET GUN with 3/8" nylon MESH for CATCHING SHAD in LAKES & RIVERS....I NEED ASAP !!! IF YOU CAN MAKE ME ONE...HOLLER !!!

Question by MurrayB15    |  last reply


Shouldn't we have a contest on all things green?

Anything with plants goes

Question by nathanfunnk    |  last reply


I have idea for infinite energy!

I have idea for an infinite energy or perpetual motion. I know that perpetual motion is impossible because it contrary with firs and second law of thermodynamics. I have learned those laws on  school too but I asked my physics teacher ( I'm in high school now 16 years old) and he said that it looks possible. The problem is that I'm from Kosovo,and there is no any labs of that type where I can make my experiment. If you have any idea about any of this labs which are interested on infinite energy experiments. I would appreciate your help.

Question by Mrfatjonable    |  last reply


Selling Things at School

So my school is having a fair, where we can sell anything we want. Any ideas? It needs to be able to be sold from 5-10 dollars.

Topic by Batryn    |  last reply


Playing Music on Arduino from EEPROM?

Hi,I want to make a device that has a few audio tracks avalible to be played from the press of a button. I want to have the audio tracks stored on something like an EEPROM because pcpartpicker I am not going nba reddit to be changing them very often. What is the best way to use an external EEPROM that is large enough to store an audio track (about 700kb)? Would I be better off trying to use some other type of storage device? reverse phone lookupThanks!

Topic by MonilGomes    |  last reply


What is the maximum voltage permitted by an arduino?

Hi guys, how are you all ? I trust Jesus the Almighty God to keep you all safe as He has done for me, Glory be to Him. I am working on a project using the arduino that requires the arduino to be able to move around but not always be connected to a computer. I want to put an external power source but I am not sure the maximum voltage the arduino can handle. Please assist me by telling me the maximum amount of voltage an arduino uno can handle. May God bless all of you. 

Question by GJM1122    |  last reply


Converting sound to ultrasonic

I need to convert a bird sound from the audible level to the ultrasonic,  close to the the 20khz level. as long as we human cant hear the sound.  My question is,  what is the best method to convert this file? thanks in advance

Topic by bujuk    |  last reply


E-bike modifications

For a few years now the popularity of electrically assisted bikes, scooters and Seway like devices is growing.If you see all these nice Youtube videos of people enjoying a ride without actually doing anything then you often want to join.In most countries though anything with two wheels and a motor is somehow classified.A nice way to for example prevent someone to run a 2000W E-bike at 120miles per hour down the freeway...There is a limit in terms of motor or power on the wheel, sometimes even a combination of both.Anything above and it is actually a motorcycle by definition.If you are in a country without such restrictions and clissifactions then read something else as nothing here will apply to your ;)What is the difference between an electrically assisted bike and an electric bike?The most common regulation for E-bikes is that they only drive the motor if you actually pedal enough.Even with higher power motors they are usually just restricted in the max speed at which the motor still helps.For example you get assistence up to 25km/h but above you are on your own.An electric bike or scooter does not have this requirement even if there might be working pedals on it.Here we have restrictions on the max power that is allowed and often also a max speed that can be reached.What does it mean if I remove restrictions from my E-bike or scooter of sorts?Without any corresponding road or vehicle laws and regulation nothing at all.In most countries though you would turn your fun toy into a motorcycle by classification.As such it would need to be conform with everything a motorbike needs to fullfill.However, you can't register it because it was modified and never intended or designed for this, it would be illegal.It is no problem to find info on the WWW on how to remove any possible restrictions, install stronger motors and batteries plus heaps more.But should you risk it?What happens if my mods are illegal and I cause an accident or get involved in one?If we trust statistics then the morojity of electric bokis or scooters involved in accidents is modifed to get more than the allowed power.The statistics however conviently fail to show how many accidents were actually caused by them.This means we can assume the same that the cops or forensic investigators assume: Unless confirmed to be legal the thing has illegal modifications.With that comes the legal approach on any rider that caused an accident with serious injuries or worse.Without the modifications you would get a slap on the wrist unless you were careless, after all accidents happen.Modified however you face several problems.a) You illegally created a motorcycle that is not approved for the use on anything but your own private property.b) As it is now classified as motor vehicle you will be charged with driving it without the proper licences, driving an illegal vahicle or a combination of both.c) With serious injury or death on the table you are no longer a kid having some fun on his new toy, you are a serious criminal.With all three boxes ticked you are likely to end with a jail sentence.Is it really worth the risk?Get a license and a real motorbike with numberplate, insurance and all - no scooter or E-bike will give you that feeling...If you are still not fully convinced then imagine how it would be on the other side of the story...You come home from a nice and speedy ride on your modified E-bike and the police is already at the door and your parents in tears.It was not you but someone else on a way too fast E-bike that got your little sister into hospital after getting hit.And since the rider knew what he was up for he made a runner...How would you feel here? Always consider this feeling when you think it is worth putting other people in harms way...

Topic by Downunder35m  


Very Frustrated - Instructable Won't Publish!?!

Okay, so I'm a professor and I have a nice project to publish.  For a first time user of this site, I'm thoroughly frustrated with the lack of detailed feedback when something is wrong.  I would fix it if it would tell me.  Usually I just walk away thinking that the thing is simply not worth the time, but the reputation of this site gives me repose to try to find out why. My instructable was saved and shows up in my drafts.  Great. I hit publish and it goes to a page to request keywords and category.  Great. I put a minimum of 2 keywords and select a category.  Great. I press "yes, publish my instructable" and the page refreshes, clearing everything I've entered. After doing this ten times with no other results or feedback of what the problem is, I find myself writing this topic in hopes somebody knows why.  Whatever the answer is to this dilemma, its kind of ironic that the instructable site is so lacking in basic feedback when there is a problem.. Oh well, I hope you understand my frustration.

Topic by Pr0f Most    |  last reply


How can I get a set piece (for theatre) to move on it's own?

I'm helping a small community theatre with their play, and I thought it would be a cool idea to have the sets move on their own.  We don't have a lot of money to do it, so I was thinking if I could get a small toy car motor or something, it could work.  Please help! I need all the ideas I can get!

Question by mturn93    |  last reply



Arduino joystick to act as 2 joysticks

Hi guys hope some 1 can help me out I've made a 3 axis joystick for my computer using an arduino Pro micro which works perfect however ide like to be able to flick a switch which would then make that joystick work as another joystick so would turn a 3 axis joystick into 2 3 axis joysticks if that makes sence I've seen it done but can't find any info on how to wire it or how the code needs to be altered as I'm new to coding so not the best any info would be greatly appreciated thanks

Topic by LurcherK981    |  last reply


HOW TO RECYCLE WATER DISPENSER?

Hi everyone, Well I saw our old and broken water dispenser just today and I'm wondering of some ways to recycle this one. Any idea?

Question by GlenntootS    |  last reply


I want to make an audio-to-vibration bracelet for my deaf partner. I need help!

I have a new baby and my deaf wife can't hear the baby at night.I want to make a bracelet that vibrates with sound over a minimum volume.I thought about using a Raspberry Pi Zero, but it seems like overkill (and large!). Is there a simple circuit I can make that could house a microphone, vibrator, battery and some chip to make it work? I'm pretty green to circuitry in general so need some handholding if possible.

Question by oodavid    |  last reply


What is this tool

We use this at work for cutting mesh, but would like to find another one as a spare, but dont know what it is? Not sure if this will be the best forum to use ? Any help with finding one would be great 👍

Question by Bodney    |  last reply


Supercapacitor + Solenoid + MOSFET?

I am designing a coilgun with three stages. Each stage has 1mm thick copper wire, with 32 turns across 32mm of length (1000 turns / meter). There are 4 layers with the same wire, length, and number of turns on each stage. Each coil will be powered by a 100F 2.7V supercapacitor (assume charging circuitry has been implemented). With those values, I have calculated that the resistance of the coils is about 0.1 ohms. With a 2.7V capacitor, I can get almost 25 amps of current through the coils, resulting in a total magnetic field of about 0.1 tesla. If I wire the coils in parallel, I get a resistance of 0.05 ohms and 420 amps through the coil, resulting in a field of strength 2 tesla.Now, the problem I am running into is shutting off the current at the right time. I found a MOSFET used for 3D printers that says it can handle up to 280A (360W at 12V or 720W at 24V). If I use thinner wire, I can decrease the current to below 280A which I suppose is powerful enough for the coilgun.Since I will be using an Arduino or similar microcontroller to manage the timing for the coilgun, would I be able to use this MOSFET (linked below) to shut off the current using a signal from the Arduino?https://www.aliexpress.com/item/33059582602.html?s...

Topic by BiaxialObject48    |  last reply


want to make wyborne helmet from movie Coraline, how? Answered

I want to make the helmet as much like it as possible. and maybe the bike 2

Question by DehLeprechaun    |  last reply


About embedding YouTube videos on instructables

How to embedding YouTube videos and links to instructables project in smartphone.

Question by Science mode laboratory  


HOW MUCH DOES PUBLISHING A GAME INTO PLAYSTORE COST?

Right, so I already made an awesome 2d mobile game and i am planning to sell it on the market (Playstore,Appstore) or just put it there for free. Does anyone here knows how much possibly will it cost overall? (license,publishing) . please list down below the things or requirements i need to comply if ever.please consider my.i hope you won't ignore this, thank you in advance.

Question by glennmarksovan    |  last reply


Maker/AI projetcs @ Miami/Flairs - call for papers

Hi makers! We are chairing the 2nd AI for Internet of Things and Fab Labs/Makerspaces special track @ flairs (The FLORIDA ARTIFICIAL INTELLIGENCE RESEARCH SOCIETY) at Miami Beach, Florida - May 17-20, 2020We are inviting interesting projects to submit to this special track!!!When we made this special track we wanted to give fab labs and makers the opportunity to get together in this academic environment to talk, exchange experiences and also to get this opportunity to link academic research, the maker movement, and personal digital fabrication.hope to see you all in Miami !!!http://www.invenio.com.br/flairs/

Topic by decoP    |  last reply


Rewinding a DC motor for different voltages

I modified small DC motors, like used in toys and such but now I have one that requires to do it properly.Motor in question runs on 24V and uses about 3.5A under full load.Drives a high pressure water pump on either side of the shaft.The rotor is basically empty with just a few turns of wire and lots of empty space.I assume the same model is used for multiple power configurations by the manufacturer.For the toys my basic approach was to just calculated the number of turns or to count them when removing.From there I get the voltage per turn and can rewind accordingly.So in theory and by blissfully ignoring all higher things involved I could do this motor the same way.Right now I see 10 windings per coil, so with thicker wire I would use 5 to run it on 12V at roughly the same speed.Only problem is that thing then would use around 7.5 to 8A when running under full load and get quite hot.I need the speed to keep the flowrate at the same 7.5L per minute but I also need the power to be able to still get the 120PSI from just 12V.Isn't there any winding trickery that would allow me to reduce the required current a bit without sacrificing on speed or torque?

Topic by Downunder35m    |  last reply


How can I generate electricity from a spinning wheel?

How can I turn the spinning of a small wheel/gear into electricity and then subsequently charge a battery with it??

Topic by SiliconSoul    |  last reply


How to make an 'Ashley Too' from Black Mirror?

Hi Guys, My girlfriend is planning to dress as Ashley O from the Black Mirror episode 'Rachel, Jack and Ashley Too' for her Birthday party in November. As a nice surprise I'd like to make her an Ashley Too from the show, bonus points if I can fit it around my Alexa. Was thinking of using an Old Air freshner for the body, hollowing it and fitting the Alexa inside.Any ideas on how I could build the head and light it? Fimo for the hair maybe?What about the arms and adding some basic articulation?Would love some ideas!

Question by flakjack    |  last reply


i start my asus laptop goes rite to a password it is not the login screen comes up b4 i can even get into bios?

Someone has played a cruel joke on me and i cant get into my asus x54c windows 7 laptop. when i turn laptop on it starts and goes right to a password which i never entered. I cant even reach the bios to go in and change anything so windows password recovery wont work for me and i cant change any of the boot devices. Any suggestions?

Question by dragons4life    |  last reply


Handheld, easily concealed helium cylinder?

Hi! I'm looking for advice on where to find or how to build a handheld helium delivery device. I just need to blow up 1 balloon at a time for a magic trick. The device needs to be small enough to hide in my hand/be ditched in my pocket after I've blown up the balloon. Any advice greatly appreciated! Thank you!

Question by AgentEFG    |  last reply


​Teachers! Let's Connect!

Hi, everyone! I'm Jess.Before joining the team here at Instructables, I was an Elementary STEM and ESE Teacher, and I have loved art and maker/DIY projects pretty much my entire life. Recently, I’ve seen some really awesome and inspiring projects and noticed that the authors were teachers, so I thought it would be cool to connect here and share what we're working on with other teachers who also love to tinker and make. I'm so excited to learn about what you all are up to and celebrate your crafty, techie, maker awesomeness! :DFeel free to say hi and share about the things you love to create or link to your most recent project in the comments below.

Topic by WeTeachThemSTEM    |  last reply


Flame broiler Magic sauce

I go to a place in Southern California called flame broiler,they have the best teriyaki sauce(they call it magic sauce).Im very picky when it comes teriyaki sauce,i dont like the alcohol in it and it needs to be sweet and viscous like maple syrup.Im trying to make a copycat recipe of the magic sauce if any one can help.

Topic by cyzco    |  last reply


Bluetooth speaker not turning on?

Hi, i made a basic DIY Bluetooth speaker with a glass box. I used one 18650battery from old laptop, a charging module with protection circuit inbuilt,one stepup module to step up 4v to 5v and a 3w amplifier. It's a basic project, but the thing is WHEN I TURN THE SWITCH ON(AMPLIFIER POTENTIOMETER IS OFF) I SEE LED BLINKING ON BLUETOOTH MODULE, MEANS IT'S WORKING ,THE CIRCUIT IS OK. THE MOMENT WHEN I TURN ON THE POTENTIOMETER ON OF THE AMPLIFIER THE SPEAKER JUST SOUNDS LIKE "TICK" AND BOOM EVERYTHING SHUTS OFF. I TRIED TO MEASURE THE VOLTAGE COMING FROM STEPUP MODULE SAYS "0"V. SO I PLUGGED A CHARGER ON CHARGING MODULE AND THEN TRIED TO TURN ON AND FIRST 2 SEC SPEAKER MAKES SOME SOUND AND IT TURNS ON AND PLAYED SOME MUSIC, IT WORKED GREAT. THE THING IS WHENEVER I'M TURNING ON THE AMPLIFIER VIA POTENTIOMETER OR THE POTENTIOMETER IS ON AND I SWITCH ON THE POWER FROM THE FIRST SWITCH THE POWER CUTS. SO WHAT'S WRONG WITH THE SPEAKER. PLEASE TELL ME :(

Question by Sayan_trex    |  last reply