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Ok so i have a atx bench power supply i made and now i need to be able to put a Adjustable Voltage Control dial on it so i can go from 0v to 12v how do i do so? And can i use any spare parts from around the house?

I encountered the following unfortunate bugs when using Google Chrome to publish my latest instructable.The floating panels and sidebarsThe right-hand sidebar masks what you have written when previewing your text.Even when the sidebar is minimized it still masks the bottom line of text. The side-bar should be anchored to the top of the screen ...Try saving your work then click "You" to exit your draft. The list of options appears beneath the horizontal top-panel making it impossible exit your draft. I got here by closing then reopening the browser :(HighlightingThe editor for creating this topic allows you to highlight your text and see the highlighting immediately.When writing an Instructable the instructable editor doesn't immediately show the highlighting. You only see the highlighting in the Preview mode.

So as the title states I want to design an audio system, I purchased an old shortwave radio someone gutted, but the case is in great shape and looks really cool, would make a killer looking amp.  So a little background, I want to make a stereo amp I can hook up several inputs to and my speakers; likely a turntable, iPod, radio, and whatever else I feel like.  The radio came with a nice little 5 position rotary switch for that.  The main problem I am facing is what ICs I want to use, and what order.  I have not dealt much with audio and at first I thought of buying a radio and just putting the guts into this unit, but I thought this would be a good project to dive into audio work.  You can't learn if you don't push your bounds a bit, am I right? The first IC question is about chips like the PT2322.  There are several I have looked at that use a microcontroller for control, and I am not against using an Arduino Micro in this unit, but I am unsure of how the acknowledgment bit works.  The data input seems to just be a shift register, data gets clocked in, then latched.  Data is fed in in 8 bit strings, but then it mentions an acknowledgement bit as a 9th bit.  Is this bit for the latch, or is there a 9th bit fed in before everything is latched?  Should it be hi or lo?  As well I was looking at the commands, several commands have 7 of their 8 bits written as a *, does this mean that those bits can be set hi or lo?  I am sure these aren't difficult questions and I glossed over something important in one of the many data sheets, and that I do not use these chips with any regularity, if ever, doesn't help either!  But I like that these ICs all seem to have a 3 band tone control and volume control built into them. If I were not to use an IC controlled by a microcontroller, I am looking at using a BA3812 for the tone controls, 5 band is a little more then I need, I really only wanted 3, not 2 but not more then 3.  Bass, treble and mid range.  But I could not find a 3 band IC without microcontroller inputs required for operation, and it was not for the lack of trying.  I can handle 5 bands though, however I am wondering, should I go preamp to equalizer to the main amp, or where would I wire in the BA3812?  This seems like a stupid question to me, I feel like an audiophile is going to come along and say, "You never put the equalizer after the preamp, it always goes here or there!" or something along those lines.  As well, regardless of where its going to get wired in, since I am doing stereo not mono, I assume I will need 2 BA3812's, but the datasheet supplies a circuit for 3 Chips as well.  Which would be suggested, 2 or 3?  I am wanting to control both left and right tone controls together, so using 5 pots instead of 10, and would also like to be able to have a balance control.  I didn't see anything about balance control in the BA3812 datasheet, would there be a good way of accomplishing that with these ICs or the use of a couple op amps maybe?  I didn't really look into balance, I should have before asking questions. For the preamp the LM1036 seemed like a good choice.  I was reading into preamps, and they seem more important for the turntable then anything else.  The way the grooves on a record are cut they boost the high frequencies so they don't fade awayat lower volumes or something like that.  Because of that a preamp that boosts bass and cuts treble is useful and improves sound quality when using turntables.  Should I use a preamp only for the turntable input or for all inputs?  If I adjust the equalizer for records is a preamp necessary or should I use the preamp and set it with trim pots to boost bass and cut treble a little, or should it be fully adjustable as well? As far as what to use for the final amplification I am at a bit of a loss.  A home theater system I have is 1500W and is adequately loud, but the system I have for my turntable right now think is only 250W I believe and it seems louder.  Never really understood wattages for "loudness"  or output on sound system.  I saw an IC (can't remember number, its a TDA though) dual 50W amplifier.  Not sure if 50W for each channel would be enough.  Advice would be helpful. As a side note, if I do go the route of a microcontroller, I found this NJW1186 with stereo input and 5.1 surround output which I thought would be cool. I really appreciate any help. Thank you

I'd imagined it activating with a momentary switch, then maybe a dial /potentiometer to adjust the time, which would definatiely be less than a minute. I don't have any way to make up a pcb so please bear that in mind, thankyou

I'm working on a 6 legged, 3DOF, spider-like robot, and I was wondering if its possible to find out how much weight the servos I have can lift... It says they are rated 3.9kg - cm so for 1 cm pole, its 3.9kg, and how can I convert that to see how much weight it can hold? the servo's that move the legs I'm not worried about but the ones that lift the chassis, make me have second thoughts.. The chassis is less than 1 pound, so at the point of the servo is about an inch and a half away, will it be able to lift.. Also, 6 servos will be lifting, so does this add all the torque together for a total product?

Hi,I'm working on building a tele-operated robot that will be able to send signals generated by moving your arms and mapping these to the robot arms. I'm looking to add an intercom system to the robot that would allow for the operator to speak into a microphone and come out a speaker on the robot and a microphone on the robot so send audio that someone speaking to the robot generates to the operator.I've currently been looking into VOX circuits and walkie talkies but all walkie talkies I have seen require both sides to use a headset. It would be fine for the operator of the robot to use a headset but it would be better for the speaker and microphone on the robot to be out loud. Does anyone have ideas about how this type of system could be implemented? Could I replace the PTT button on a walkie talkie with a voice activated switch kit available online?Thank you.

If I wanted an R/C blimp, I could control the direction easily enough with propellers, but how could I control vertical ascent/descent?Is there, perhaps, such thing as a pump small enough, yet strong to regulate the helium pressure? (Compress to/from something like a CO2 cartridge?)

Hi! I would like to create a project for the random selection of shooting targets. E.g. each target should show up and stay there for 5 seconds and if not shot down the servo should pull it back. Does anyone have the code required for random selection of servos and making sure they delay between on and off is 5 secs? Ideally the random component would ensure that all targets have an equal chance of being selected but only one at a time.

Hello!How can you select the Education categorie when writing a new lesson plan f.e.?Thanks!

I pulled 2 stepper motors out of a old printer. They look the same but there are no markings on them. Only one red and 3 white wires. I don't have them with me this week, but how could I test them over the weekend?

I have purchased a simple 4 channel relay (http://www.fort777.co.za/index.php?main_page=product_info&cPath;=800_801_946&products;_id=10357&zenid;=fvokss9s9ucgakrrn9ged441hs1oushq) My Aim is to use the USB port on my TV to control the relay.  The intention is to have it switch on a lamp when the TV is powered up.  I have run into an issue and being a bit of an electronics novice I am not sure what to do.  The Relay kit as both a 12v input (I assume that is to actually power the relay coil) as well as a connector that has pins for Ground, 5v and Signal for each relay (S1 - S4). If I attach the red wire from USB (5v) to S1, and the ground from the USB Cable (Black) to ground, the indicator LED flickers and then dies.  at no point does the relay click, and the light seems unaffected whether the 12v power is connected or not.   I feel I might be missing something simple, but as an utter novice in this area I am not sure.  Any help. 

Hello, i want to know what is the diffirent between 1n4148 and 1n4448 .I  checked the datasheet but i cant find the diffirent .. Thank in advance!

I had an idea but don't know how to make it lol.This might sound a little far-fetched but is it possible to make a light that will flash to BPM from a software for example, virtual DJ? This is something I've had in mind for a while now but never knew how to go about it.

Is it possible to focus a beam from an LED so that it makes a laser-like beam? Could it be made to burn? I've heard of simulated lasers that sound like they use LEDs focussed into a beam.

At one point, I think it was possible to view photos I had uploaded, whether I'd used em in an ible, draft, or topic.But I can't seem to locate those at the moment. A little help?

I just got a 3 pin wall power socket (240volts/EU style) that comes 2 built in USB charging ports. I replaced my wall power socket with it and both the USB charging ports works fine and so does the power socket (when I connected my 240volt desk lamp to it). However, when I happened to make a call on my iPhone whilst it was charging (from one of the usb ports), there was a "tingling" sensation when I held the phone to my ear.  This is a repeatable process... turn the switch off/disconnect from the USB port and the "tingling" goes away, turn it on/connect the phone to the USB port and the "tingling" is back again. There is obviously a grounding/current leakeage problem from this "Socket".  I can't feel the "tingling" when the connected phone is being held in my hand. It is very apparent when the phone is held next to my ear.   I have ascertained that the connection to the power socket is correct ie.  Live, Neutral and Earth are all correctly wired. QUESTIONS: 1.  Is there a way to detect this leakage other than only using my ear ?  ( I need to show the manufacturer that this is a real problem either with a video or be able to measure this leakage objectively).  Is there a electrical device /detector for this ? 2.  How dangerous is this situation ... Could it have electrocuted my family ? 3.  What is the cause of this ?  Is it because of poor earthing/grounding in my house wiring ?

I want to make paper mache garden pots, if possible, so it would be paper/flour and need to be covered in something that would not ruin the artwork/shape. I have not tried any sealants out yet, thought I would ask and see if anyone has experience with this or something similar. I have looked up some Kryolan products, but am unfamiliar with what these sealants and stuff even do. Like what is epoxy or resin? Please help me out, thanks! 

Hello! I've seen a ton of cool projects utilizing laser cutters/cnc machines, but the problem is that nobody in my area seems to have one/they are much to expensive for a college student to afford. I'm looking for someone with access to one that would be able to run a project or two through the machine if I paid for supplies and shipping. I want to continue creating and hopefully can overcome the challenge to do so. If you or someone you know could help me please let me know! Raleigh

I am working on making a vending machine, and I wanted to make a control board for it also. I will need a circuit that when a light activated resistor senses that a laser beam is broken by a coin falling past it, it will press multiple buttons on a calculator. (for example, if the laser beam sensing when a quarter falls is broken, it will need to press +.25=) I will also need a circuit that subtracts the amount of money a certain object costs when the button for that item is pressed. It will need to not let you press a button and display something like "you did not insert enough money" if the calculator does not have enough money added on to it. I was hoping to not need to use any ICs for it, but if I have to that is fine. I would not pay any more than I would need to buy a controller that would work for it like a raspberry pi, and if you have any suggestions for a controller or how to program it, tell me those too. Thanks!

I just wanted to give a quick shoutout to the Instructables staff and let them know how much I appreciate the work they put into this site. I don't have a lot of time to make Instructables because of college so it's very rare that I post, but Instructables was a big inspiration to me when I was younger and regardless of its appearance it's still a ton of fun to come back every now and then to spend a few minutes relaxing and looking at what everyone else has made. Thanks for all yall do. Hope your day is fantastic!

There was a topic I responded to perhaps years ago that I'd like to find again. How?

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.

In the late '50's Popular Electronics magazine (out of print) published an article "building a rudimentary computer" It was called the Challenger. It was a circuit that could play the old parlor game of "21", and utilized a mechanical stepping relay to do the "computing". There was a series of 21 pilot lamps, with a 'player' and 'machine' pushbuttons. The player, and the machine, in turn, could light 1, 2, or 3 lamps, with the object being to avoid lighting the last, or 21st lamp. The machine would invariably win. The secret is that within the number 21 there are five groups of 4, with one left over. Whatever number the player selects, (1, 2, or 3) the machine then selects a number that, when added to the players choice, totals 4. (player 1, mach. 3 / player 2, mach 2/ player 3, mach. 1) It would seem that today's processors and LED's, could handle this task easily. Would you, or someone you know, be interested in designing such a circuit as a project? I built it back then but I'm afraid my knowledge is stuck back in that time and would need instructions remenicient of that era.

These circuits are TX and RX 433MHz RF module. Can somebody tell me how these circuit works ? and can somebody show me its block diagram ?

Is there a reason Instructables is deleting comments and replies without a note or considering to grow a backbon so we get answers?You recent site upgrade has offended and disappointed long standing users, now you add insult to it by deleting their comments.I call this censorship and it should not happen.In the deleted posting was nothing offensive, nothing wrong - the only thing in there highlighted the utter disappointment of the user.What comes next next? Deleting accounts of users who prefer to have an opinion that differs from the official Instructables.com viewpoint?What are you so scared of?If you do major changes you have to consider that not everyone likes them.As it looks now you have a hand full of users liking the kids look and features while the rest of the community is disappointed to say it nice.Deleting their comments in this regard won't fix the problem, it only adds to it.

Hi ,May someone guide me to make "Safe Ground" project that has already instructed here but I need its circuit diagram and procedure to make Safe Ground project please.

I have a 1.1μ capacitor with voltage capacity of 440V. I am inserting a 1000Ω in series. My question is how much time will it take to almost completely charge if I'm applying 12v at 0.5A?

I have a single phase 3.5 hp AC motor, I would like to convert to a 12 volt DC.I'm no electrical expert but I think it can be done.From watching youtube vids and asking Mr. GoogleI understand a DC motor runs slower say 1750 rpm,where my AC motor spins at 3,450 rpm.I also understand a DC motor has brushes.Besides the speed being different, and changing the cord out,is there any reason WHY this couldn't be done?Any potential drawbacks?Any help or knowledgeable advice would be much appreciated.Thanks guys,skip

So I'm thinking of learning about PIC micro-controllers. I'd like to know some info about it. In what language is it programmed in? Is it similar to C? How is it different with STM32 controllers? (Never used an STM before, though).

So i made a laser alarm system some time back, it worked good but had one fault, more like a limitation. it made the buzzer ''buzz'' only when the laser was interrupted and the buzzer turned off when the laser was allowed to hit the photo sensor again. i wanted it to stay on until turned off by a switch. someone suggested something called a monostable flip flop but i had no idea what it even meant, then i saw something called silicon controlled rectifier or a thyristor, but i also learned that they have to be made using a pnp and npn transistor, what i cant understand is what transistors should i use to replace the npn transistor on my circuit, the tansistor on my cicuit is 2n3904, input voltage is 5v

Am I the only one that's not seeing the friendly PDF Download on the the web articles?

Dear Forum,I am wanting to make a print of a model steam locomotive wheel that I can use as a pattern for making sand castings for iron.I have no experience at all of 3D printing but I do understand that it can be used very successfully for this type of process.I need the attached drawings made into a print to enable me to pattern this is sand casting iron. Where do I start as I have no idea of the software required.Thankyou all for your help in advance.

Have you noticed any changes here? Well, I am experiencing the biggest changes on this website. Everything is lot cooler now! I really enjoy the community now. Everything here is new and even the project pages are super cool. They add "Add Tip", "Ask A Question" buttons... all I can say it is super cool now. I like the changes.... what can you say about the biggest change here?

I've published a new tutorial recently, but it's launch status is not updating.I has around 16k views, but if I check the launch status for the last month it only show zero visitors.

As the title says, my recent instructable ( https://www.instructables.com/id/Digispark-Contro... ) keeps getting unpublished, becoming a draft. I have to go to the edit button and then publish it again.It has been submited to the rc contest and approved. Could this be a reason for this to happen, like a bug?Why is this happening?Thank you

Hello, I have a very large amount of manganese dioxide, which i wish to turn into manganese metal, however, i have a problem with reducing it with carbon, which is that i dont have a furnace, or even the materials for a makeshift one, as i found out all the bricks that are sold in this state, are all sand or cement, no clay, not even at the hardware store. I was wondering, if there is any way for me to get manganese metal other than reducing with carbon, such as electrolysis of manganese in some soluble form. thanks

I am working on project with a flashing led strip, 6 bulbs in total. The circuit includes a 555 timer.  At first I was using a 9v battery but then realised that battery is way to big. A coin battery (CR2032) would be perfect. How can I power the LED strip using the 3v coin better? I am pretty new to circuitry so any help would be greatly appreciated. Thanks in advance. 

I remember that it was possible to see the traffic sources in the stats of an instructable. Did this feature disappear with the site update?Thanks!

What are the maximum size and resolution for images ?Are images automatically resized on upload ?Thanks!

I'm building a folding ramp to replace my tailgate on my truck. It's going to be used to load/unload a ztr lawn mower. (It's been built primarily from discarded bed frames, with the addition of some expanded steel grating.) Because these mowers are back heavy, and low to the ground, a longer ramp is needed than you need to load a conventional mower. My solution is a spring loaded 8' ramp that is comprised of two 4' sections that fold down and out. It functions, it fits, the mower goes up and down it ok. The problem is that it is so heavy, that after it comes down about 2/3 of the travel, it is very difficult to control. When it comes down hard, it puts tremendous stress on the center - where the two sections of ramp meet. It can be hard enough to break it. I know my welding isn't the best, but that's really not the issue here. This is a design problem. I'm going to post a few pictures, to better illustrate my situation, and to show some of the things I've tried to soften the blow. The picture of the partially folded ramp was taken at the point where it begins to get difficult to lower without losing control. So, to clarify, I need a way to lower and raise the ramp with more control, and or soften the blow towards the middle.  The springs I'm using are 140lb garage door extension springs, the largest springs available at any big box home center. I need to get this finished yesterday, so I'm going to try some things while I'm waiting for a response, like move the springs back further in the bed to put more tension on the whole thing. I'll also post this to the welding web forum, but I started here because I've got a lot of faith in the ingenuity of the instructables community. If we get the bugs out of this thing and anyone wants it in instructable form, I'll do my best. Thanks for reading the War and Peace of ramp questions. -Amir

Greetings all, I just aquired a rather expensive hat,however, being the kind of person who reads instructables on a regular schedule, I want to improve it by adding several pieces of velcro, that I may attach various useful or decorative objects to it.I don't wish to sew it because,A: I'm terrible at sewing.B: the hat has an inner lining, and I don't want to attach both layers together.so this leaves glue, I was wondering if there were any experts on here with knowledge of fabrics and fabric glue.what kinds are there?what kind should I use?will fabric glue makegore-tex melt? catch fire? acquire magic powers and cause amphibians to sing?

I love Tesla coils its very initial level of me ...i have just started

..because it doesn't work. the gun is hot but it doesn't squeeze out the glue anymore. the trigger is hard and 3/4 of glue stick is still in the tube.

I'm making a usb charger and can't understand resistors, so can someone tell me what kind of resistor I need to make a usb charger from 9v battery?

What happened to the categories? I am completely lost on the site now. If this is the new norm, them consider my subscription canceled.

Until recently every article had a few links to similar Instructables top right (just under the equally useful and equally missing other posts by same author box). Did I somehow accidentally change my layout preferences or did this get helpful information get nixed for the sake of a cleaner layout? If so, please restore that functionality. Without it each article is a dead end. You're killing my flow, man.

I'm still scared to post an instructable that won't be recognized as a good one ever since I posted my first instructable. I then removed it because I didn't get into a contest, and didn't have many friends(as I will explain next).I was scared and still am because the contests so far seem to be rigged. I feel like this because of the way the Instructables' voting system works. So let's say we create an instructable and don't care how crappy it is. Now, let's assume we are extremely popular on social media, and ask all our followers to vote for us on our instructable...See where I am going with this?All we have to do is make our friends hit "Vote", and your friends don't care if your 'ible is good; they love you so they will vote for you. Thus cheating your way through the system.I swear this happens for every contest. There has to be a better way to determine the winner from the moment the author posts his/her instructible. This cheating wouldn't make it fair for many of us, and especially not for me(I don't have that many friends) :(If this cheating method works, then isn't voting similar to a "whoever has the most friends" contest?My suggestion:I understand that voting helps separate the weak from the professional Instructables, but I feel like a better way would be to require those already entered in other contests to vote for a contest they are not entered in. Thus, the biased friends wouldn't affect the polls. For example, say Lily entered the Flower-shop contest. In order for Lily to enter the flower contest, she must vote for at least 2-3 people in another contest (except the flower-shop contest, obviously).Make the Instructables list randomize everytime you refresh the screen on every contest website here on instructables.com This way everyone will have a chance to be seen throughout the months of voting.I feel like these suggestions could be adjusted with your comments. Thank you for reading.

I know I will not be able to completely rely on solar power to power the blades of my quadcopter but I would like to extend the flight time as much as possible.  I was looking at this url and started getting interested in trying to create a small panel array on the arms of my quadcopter to help replace some of the power in the battery (trickle) while using the battery for flight.  Doug Paradis had some helpful insight to the OP's question but some of it went over my head.  That's what lead me to ask my own question to make sure I'm talking about quadcopters instead. So currently I have a light weight POS starter quadcopter that has the following battery being used... - FB752540 - 136 Li-Po - 500mAh 3.7v - 4K07 1.9Wh I have some internal space to mount small items but I would try to keep the weight down as much as possible.  I was hoping to start my own DIY project to learn more about solar power and the entire process. I'm guessing I would need at least one solar panel (small), something to convert the power, and some type of regulator to trickle the power into the battery.  Any ideas as to how I would do this? Thanks! Arvo

Several times now, I've seen indications comments were made about one of my posts, but scrolling down, they don't show. Has the format changed so much we now have to jump through hoops to get to them?

Hello! I read instructables for a very long time, and today I decided to create an account. So, I've done it with my GMail, and got very strange name - "ВикторЦ1". IDK what does it mean, and how to change it. So, I always use nickname "Tsycunoff", and my real name is Victor Tsycunov, or Виктор Цыкунов in cyrillic. Saw this I thought - OK, lets create a profile manually, but i saw that name "tsycunoff" is already using. At settings pannel i didnt find form to change my nickname.So, the question is: How can I change my nickname at instructables.