Simple math? Answered

This is one of those crazy things put up on Facebook. From what i can tell most people are getting this wrong. But you follow the rules for simple math -- Rule 1:   First perform any calculations inside parentheses. Rule 2:   Next perform all multiplications and divisions, working from left to right. Rule 3:   Lastly, perform all additions and subtractions, working from left to right. So it is       3-18+2= -13    And yet people think I am wrong ??   I simplified it even more for them ---- 3+2 =5     5-18= -13  Why are so many getting this wrong?  Or maybe I am wrong---- time to go back to grade school I guess.

Question by Vyger   |  last reply


Simple CNC question... Answered

This is probably really obvious, but I wanted to know if there is a better way.  I was thinking about how I would go about making a simple "mounting plate".  Then I realized that wouldn't I first have to cut it to size and then mill out the holes.  But then the since I had to cut out the plate it kind of takes the point out of the cnc, because I wouldn't be very accurate for the outside dimensions.  So is there a way to machine the outside, even though it would be in the cnc's vice? Thanks in Advance! AI

Question by JaredsProjects   |  last reply


complicated simple instructable

I'm working on an super efficient portable rechargable lithium-ion usb charging pack (if that make sense). If I were to make an instructable basically all it would say is make this PCB and solder everything. Should I just post when I'm done on like a forum? The only reason this is complicated is because it has about 30-40 electronic components.

Topic by guyfrom7up   |  last reply


Simple Robot Ideas?

I just got a soldering gun, and i really want to use it. but my knolegde of electronics is limited (and so is my wallet), so does anybody have a cheapish, simple, and cool robot idea?

Question by schoonovermr   |  last reply


Simple Electronic Help

I'm currently building a small hybrid solar panel car for a school sompetition(runs off of batteries or solar), and I need a bit of wiring help, here's my problem and some other stuff. I have 2 SPDT switches and 1 DPDT switch. I'm using one of the spdt switch for on and off, the other to switch from solar to battery, but i need help for the dpdt. There's 2 sets of solar panels (2 pairs of 3 hooked in series, for simplicity sake, I'm just going to say 2 solar panels), and I want to hook them up to the dpdt switch and the motor and the battery so that: I can turn on/off the motor (easy), switch between solar and battery (easy), and switch between paralell solarpanels or series (what I'm having problems with), any help?

Topic by guyfrom7up   |  last reply


Simple Animatronics help?

http://i240.photobucket.com/albums/ff32/evildrew81/people%20and%20stuff/saw_doll_tv.gif -Can anyone help me with making an animatronic mouth such as the one in the video? Can I use a RC Car servo? -Can someone also help me with a neck that can turn? Could I just use the back servo of an RC car so that it goes around Clockwise, and in reverse, Counter-Clockwise. -Is there a remote for servos that can controll up to 3-4 servos at once? Any help will be appreciated. Thanks.

Topic by ChaoBreeder   |  last reply


Simple picaxe robot? Answered

A simple picaxe robot controlled by a remote using picaxe 08m2

Question by e=mc^2   |  last reply


Simple circuit simulator

Hello,I am a hobbyist , and I am looking for a simple circuit simulator that can tell me if my circuit is working well.Just simple to use not like those professional that are hard to use and oriented to professionals.Does anybody know about?thanks to everyone.

Topic by Leonida61   |  last reply


Simple guitar amplifier?

Just curios, is it possible to build a (very) simple guitar amplifier out of  2x2N2222, a 8 Ohm speaker, a battery and some resistors? Note: I have a guitar cable with another and cut off.

Question by MaracKoMarac   |  last reply


A simple decision maker

Hi    i am a very confusing guy and cant take decision easily so want to create a simple decision maker which helps to make decision whether to do or not

Topic by Rohit.panwar001   |  last reply


Simple Hook-up?

Does anyone know a super simple game console hook-up? I don't really know much about circuit boards, and electronics, but I'd like to learn. What I mean by simple is: a power supply plug for it, AV cable plugin, an on/off switch, controller ports, and game cartridge port. To be specific, I'd like to be able to build a smaller, simpler version of a Sega Genesis, or N64, or whatever.                                                             --- Thanks!!

Topic by kenizl86 


Simple Comparator with a LM339N

Hello, I am trying to make a simple comparator with a LM339N. I don't understand what is wrong with the circuit. The output is always low, even when the inputs are reversed. The schematic is attached--the schematic doesn't include the two 100k ohm pull-down resistors on the inputs.  Thank you.

Question by dboone628   |  last reply


Simple Resistance Question

I am wiring some LEDs in series-parallel using a 9v battery. The schematic I've been looking at online as a reference shows resistors being used but doesn't say what size. Here is the layout: |-- LED -- LED -- LED -- resistor?--| |-- LED -- LED -- LED -- resistor?--| |-- LED -- LED -- LED -- resistor?--| |--9v-----------------------------------------| I assume it's a simple calculation but I haven't worked with this stuff in a few years. Thanks in advance.

Topic by L3fty   |  last reply


Simple timed LED?

I need a way to turn on an LED after a certain amount of time (e.g. 5 minutes) then keep it on until a momentary switch is pressed. a very low power consumption if possible, because it's going to be wrist mounted. thanks in advance

Question by DrVonTrap   |  last reply


Simple audio amplifier?

Alrighty, I'm a n00b to this world but I'm really into it. I just bought a simple amplifier kit and put it together. It is a stereo amp but I am only getting output to one speaker. The only problem I can think of is how i rigged up the inputs. I took a 3.5mm jack and combined the ground from the left and right channels. Can you not do that? How do I fix this without running two individual mono channels? Thanks in advance!

Question by abroadhead   |  last reply


simple program counter ? Answered

Hello  , I need help,I am posting schematic. I don't understand ,that   how program counter know some instructions  (jump , branch , subroutine call ) I have attached two diagram.look the 1st diagram.I am using 4 counter. how to improve that circuit for program counter .

Question by vead   |  last reply


Simple PCB etching? Answered

To print out a pcb circuit you need magazine paper, a transparency or photo paper. Well I was just wondering if I can just take magazine paper out of a actual magazine if its a blank page and print right on to that and then iron that on to my pcb?

Question by Kante Tech   |  last reply


simple 5v regulator?

Today i made a shaking generator for a shaking flashlight.i am using a 5.5v 1F capacitor as storage device.but output of  the generator is 3v~6v DC.how i can regulate the output ≤5v?.i am looking for most simplest and cheapest method. can i use a resistor?

Question by vina1991   |  last reply


simple logic circuit

Uuhhh..I'm not really sure about this..i'm an electronics engineering studentand my instructor in Logic Circuit and Switching Theory requires us to make a project which will include logic gates.now i searched in the net for some ideas i found two..but i know i shouldn't copy their projects..can anyone help me?link2link1thanks guys!

Topic by hazelcharisse   |  last reply


Electical simple Project

Hi dear ,                      My name is Javaid . and I am Male  of 24 Single, and I am from Pak . Dear I want to Make a Best Friend in this Comuninty that He or She. so Please i want to Discouse my Personal Infomation He/She about my Project of Electrical... this is my E-mail ( ja_na146@yahoo.com) so Please send me Email who help me and make me a good Friend .. thanks a lot. your's. Javaid

Topic by ja_na146 


simple power supply

I have a project that needs a 24VDC input, at only about 300 mA. I don't have any 24V power supplies, wall warts or anything else lying around, but what I do have is a 120 in, 24 out transformer, a bridge rectifier, and a large cap. Is there any reason why I shouldn't just use those? I'll put a fuse on it. I have some 317 voltage regulators but they dissipate too much to provide the full 24V. 317s are short-protected and the like, which obviously my little kludge wouldn't be, but beyond that, is it a bad idea? thanks,

Topic by deadbilly   |  last reply


making a simple phone

I'm wanting to make the simplest phone ever that can play music and only receive calls, I've designed the simplest circuit but have never done it before, so far on my list i have. areal aux out charger hole battery micro sim slot micro SD slot microphone speaker 6 buttons= play button pause button skip & back up button receive call  end/ decline button i have no idea how to programme a circuit board or how to use a bread board and may need some help, but this is all i want this circuit to do and at a very small size.  can anyone help or tell me how, I'm happy to pay a bit.

Question by JoshuaM57   |  last reply


Simple, speaker question. Answered

Hello, All I want to do is create a very low, and reasonably audible hum or drone from this speaker ; about as loud as a person humming as hard as they can before their throat hurts and they start coughing. Is it possible to avoid an amplifier and just run a voltage into it so that it just makes a single tone as described ? If so: I found this big broken speaker in the road. As you can see, the Cone is missing a section, but the surround and spider are intact. The cone is credit card thickness plastic. Is it feasible to just patch it up with some similar plastic and contact adhesive; it does not have to be a good sound, just a drone. I realise that my grasp of electronics is child like and readily accept the impending abusive comments and links to the Google homepage. Thank you  FOH

Question by FriendOfHumanity   |  last reply


Simple AM transmitter

I wish to make an extremely small (size and part count) AM transmitter using only a few transistors and passive components. I wish to transmit an audible tone on a set frequency.I am thinking along the lines of a transistor flip-flop circuit oscillator, perhaps routed through another. It really needs to have less that five/six small components. DIP components are too big. Small electrolytic and other capacitors, transistors, and resistors are acceptable. Transmission distance needs to be at least 1/4 of a meter, but further is better. It needs to run on between 1.5 and 6 volts, low to middle'in milli-ampage im thinking watch batteries for a few hours at least. I have read the following article but as stated before it needs to be very small. https://www.instructables.com/id/Make-a-simple-AM-transmitter/Can anyone help me out with a schematic, thoughts or advice?Thanks in advance,-AndyP.s. I can work out transistor loop timings and I understand how the Amplitude Modulation system works. Current thoughts/plans (if you can call them that) are an audible tone switching a secondary transistor loop from high (no resistor in series) to low (resistor in series) power and back. The secondry loop will be switching at the target frequency.

Topic by andy   |  last reply


Simple electronics question.? Answered

Hi =)  I needed to use a rc car remote and receiver to power some relays on and off. The car is using rack and pinion steering so it  has four wires; Steering Motor Wire A Steering Motor Wire B Propulsion Motor wire A Propulsion Motor wire B  SO when i press the joy stick forward, PWA_A becomes positive and PWA_B becomes negative, driving the motor in the forward direction. Same for the steering motor when i press the other joystick Could any one give me a way to connect so that when i press the joystick in the forward direction, relay one energizes and when i press it in the other direction, the other relay energizes so i can control 2 relays  per joystick, ie 4 relays in total. Thanks!

Question by qwerty156   |  last reply


Designing a simple circuit

Ok guys.. so i think this might actually be my first post ever here! Down to business... without giving away my design before I have a chance to build it and such, ill be a little general, and using a different scenario than my actual plan.. i hope you guys are ok with this. It will be an instructable after i get going, i promise you that. So I was hired (i'm running a small business doing custom LED work) to make a project for a league I play in. The premise is simple. We need a way to keep everyone informed as to who's turn it is for the game. As it stands, there is simply a matter of the players staring at you, or mentioning, "let's go!"  which is quite embarrassing. So the design is relatively simple. I have one button (LED center) and one switch per person.   The button signals that you've completed your turn, the switch (when moved to the OFF position [preferably OPEN] )indicates to the microcontroller, or whatever I design to replicate the microcontroller, to skip your LED button if your turn should come around again, and go to the next person in turn. Using the most simplistic way, how would i go about this? I may make a picture of my idea, but its really late and im headed to bed lol, so that will be done tomorrow.  I'll give another example, say there are 4 people at a table, and player 1 and 2 complete their turns. player 3 chooses not to play for the remainder of the session. Player 3 turns their switch off, and play passes to player 4. Player 1 goes, Player 2 quits like player 3 (switch goes to off position), and then it goes to player 4.  Pay attention to the bold in the previous paragraph. How would this be accomplished? Remember, an LED button is being pressed to signal end-of-turn. Any ideas or nudges in the right direction would be perfect. I'm not looking for a handout, so just suggest, NICELY PLEASE or link to related materials. I like learning, so handouts will not benefit me, unless you tell me WHY, so that i can remember it for next time, if there is a next time lol. I appreciate this you guys and gals. I take a lot of knowledge away from every instructable I follow along with.  --Mikel

Topic by mikelspencr   |  last reply


Help with a simple circuit

Heloo, I have hassled with this since last year. I have googled over 9000 times, yet I still remain confused, and unable to find a solution myself. I guess it's prime time to seek help from others. What I have: Lazer; 4,5 V, 150 mA 2x motor; 1,5 V, 250-300 mA 1x motor; 1V, 50 mA (vibrator motor from nokia phones, and it might work with less) The idea: I made a.. Thing.. that had 3 small motors ( the phone ones) that had mirrors on them and the lazer pointed at them, which eventually reached the wall and made made pretty stuff on it.. But that was a prototype, held together with tape, and now I have decided to make a better one. The V2 of it is held together with screws, has better mirrors (v1 had small fragments of an old hard drive disc), better motors, and looks nicer. If possible then I would like to be able to control the speed of the 2 bigger motors( to be able to create different images) The problem: EVERYTHING!!! I somehow managed to make the V1 without any resistors without burning anything out, so it only had switches and wires. That doesn't seem to be possible with the V2 that I have planned. I have read almost everything on the internet about it, but I can't make much sense of it, so I figured if someone was to show me how it's supposed be, I would understand a little more. Maybe even finish the project. What I want: HELP. You may try explaining what I need to do, but all the laws are sooo confusing. I will appreciate any and all posts, be they not on flames. But what I guess would help me the most, is if someone managed to show me exactly what components I need, and where to place them.

Topic by Mutad0r   |  last reply


How to make a simple robot with simple household items? Answered

Just want something to work with

Question by KIPPstar   |  last reply


I want to make a simple very simple audio amplifier

Hi people im a 15 year old south african,i want to make a small,very very very very simple and self powered audio amplifier that can work with cellphones.as i sed im 15 and i dont know alot about electronics,so please help me remember the amplifier must be as simple and cheap as possible just say capacitors and resistor and tel me how to make it self powered.thanks in advance,o and 1 more thing please tell me your email address because i might have questions

Question by Salesh   |  last reply


How to make a simple sound activated robot with simple motions?

Hi to everyone! I am new here and will really appreciate any help or advice on my project. Truth is, i am very new to electronics and thus, have little knowledge on how to proceed with my project. In summary, my project is basically creating a friend(robot) that will activate upon receiving electrical impulse from a mic. The motion it will have is basically the lighting up of LEDs (for the eyes) and the head tilting upwards (using servo or DC motor idk...) when sound is detected. However, i want the motions to be there for 30 secs even after there is no more sound before reverting back. I have done many research regarding this but it is just too complicated for me to understand. I would really appreciate it if the solution or advice is simple enough for beginner to understand. Also, i don't want "clap" activated, i want it to be sound activated like simply speaking normally. And i hope to avoid using micro controllers. I would probably ask even more questions in the future, so, hope i will get along well with everyone here! p.s this project is a very scaled down version because i wouldn't be able to handle the full scale electronics...

Question by DIYfreshie   |  last reply


Make a simple speaker louder.? Answered

I have a small simple speaker - just the magnet part, with no wires - and i have connected the positive and negative terminals to a simple 3.5 mm audio wire. The speakers play sounds, but at a very low volume even when the volume is max. Is there anyway to increase it?

Question by freerun   |  last reply


Keychain sized simple circuit Answered

I plan on making an Instructable about making a keychain sized simple circuit. I will be using the circuit board  shown below but I'm having inventors block. It should be able to take the stress of being jumbled up in a pocket. What should I put on it? If I use your idea I will mention and thank you in the Instructable. Thanks in advance.

Question by pgd5000   |  last reply


Simple linear motor design ? Answered

I need a simple, not powerfull, linear engine. It has to move just like an inch back and forth, chaning directions on its own when it reached the end of his stroke. Even 5mm would be enough movement. I think about of something based on a neodymium magnet in cylinder shape. It has to be as simple as possible, i don't need any control for frequenzi, because if it works.. i can work out more from there on my own. Only thing important, it has to be small, like the lenght of a half pencil and 2cm in diameter would be ok (for the moving part, electronics placed elsewhere don't matter). A normal rotating engine with a shaft doesn't work for the design i have in mind :(

Question by wupme   |  last reply


Simple Audio to Button interface?

Dear Highly esteemed members of Instructables, I've had this Idea in my head, and I REALLY want to make it possible. I have a feeling that doing so would be a cinch if I had any sort of understanding of wiring at all. Basically, this is my idea. I want to use old buttons (and possibly an analog stick) from a gamecube or n64 controller and wire them so that they play a note when pressed. I don't necessarily need to include the analog stick in my design, if doing so would make the project a good deal harder. I'm looking to include about five buttons. And if the analog stick was included , at best I would want it to move the note in half steps, up or down, but I could also settle for setting it to it's own four notes, or not using it at all. As aforementioned, I have no Idea how any of this stuff works, or if it is even possible. So do let me know if this is even something that someone like me can do. And if it is, try to err on the side of over explaining if you can help it.

Topic by jdiggs1   |  last reply


Simple circuit fix?(Novice)?

Built this circuit (see attachment) using 2 solar cells putting out about 5.5-6v (got crap meter atm) . 4 xAA 1.2v 2450mAh NiMH Duracell Rechargeable battery's. Found that its drawing charge from my Android phone quite rapidly. Will another diode before usb fix the problem and block current out of device? Or a 5v regulator in place?..... Although i read they need at least 7v to work or they will drop overall power? or am i just talking gibberish here and need a slap?! lol! some help would be much appreciated! Incase of attachment  failure or watever....Link: http://neotoy.tripod.com/archive/2009/youtube/circuit-diagram.pdf

Question by scott_shot   |  last reply


Help with simple power circuit Answered

Really quick, I have a REALLY SIMPLE circuit I'm building for halloween decorations that looks like this: http://imgur.com/dkU3LbT Basically there are 6-7 Lasers that draw 3V at 250-300mA. The most practical power supply I could think of is a 5V 2.1A iPad power adapter, with a usb cable with the leads exposed. I forgot the basics of electronics... What positioning of what rated resistors are to be used? Did I make a mistake in the basic setup? THANKS SO MUCH FOR YOUR HELP **EDIT: I suppose I should clarify. These 'lasers' are actually fully built with the drivers inside. Specifically they are those cheapie 5mw green pens.

Question by madman11   |  last reply


how to make a simple detonator?

how can i make an electronic detonator for fireworks?

Question by patriot15792   |  last reply


How to make a simple microphone? Answered

Hi, i want to make a simple computer microphone i have a microphone i removed it from a old telephone and a 3.5mm jack  with four cords 2 positive and two ground.i want the simplest way exists!

Question by ubdussamad   |  last reply


I need a simple curcuit ?

I need to turn on a 24vdc relay (apply gnd ) with a transistor. I have a 5v signal as the sourse from an industrial computer

Question by daveaprile   |  last reply


Simple Lithium Cell Balancer?

Could your balance a lithium cell by simply hooking it up in parralel for a short period of time every once in a while?

Question by snowluck2345   |  last reply


Help with a simple led circuit?

Hi all, id id like to help my son with a simple school project. He wants to mod a mouse by replacing the cover with a clear cover and adding an rgb led that he can switch with a push switch, powered from the 5v usb.  So I need a little circuit to turn on, and switch colours on an rgb led via push switch, powered by 5v.  I just want want a simple but complete circuit, not to use an ardino or anything like that as space will be tight.  Id id really appreciate your help.  Thanks Jon

Question by Jon_uk   |  last reply


Help with LEDs and simple circuits? Answered

Okay, I'm making a little LED project and I'd like help on these following questions: On most switches there are three little prongs, which ones do I connect to which wires? Do I need a resistor for a simple, battery powered, LED circuit, with 16 LEDs? If so, what kind of battery do I need and what kind of resistor? Can LEDs shine through a thin layer (3-5 mm) of balsa wood? Thanks! -popewill

Question by popewill   |  last reply


3d TV Made Simple? Answered

Okay so, 3d tv works by darkening the glasses over each eye at the refresh rate of the tv right? But wouldn't it be easier to have the tv just morph the image a little tiny bit to the right and left like 70 times a second? Look at the pic.

Question by LiquidLightning   |  last reply


Help with simple transistor circuit.? Answered

I want the LED to turn on when it's dark. But  it remains on and taking out the LDR doesn't affect it. I couldn't post a picture but i made a replica in Fritzing EDIT: The transistor is 3904 NPN.

Question by Hafiz Mohammad Shayan Tariq   |  last reply


Simple electrical insulation question. Answered

If I have a 10AWG insulated solid copper wire and the THHN insulation is rated for 600V, should I worry about a 5000V 60ma current arcing straight through the insulation if its coiled in a helical form?

Question by imMrDude   |  last reply


Simple radio transmitter question Answered

I am interested in building a small low powered radio transmitter. Searching the Instructables website I found some Instructables that have some with oscillators: Build a very simple AM Transmitter Make Your Own Low-Power AM Radio Transmitter Some other projects are built with timer chips and transistors: 555 AM Transmitter Easy AM Transmitter! Would someone please explain the theory or science, and advantages or disadvantages of the components involved when building each project? Thank you very much.

Question by blkhawk   |  last reply


Storing Simple Analog Data

Hey guys! I just got this cool little temperature (LM35) and I had a small problem. I want to upload this sketch to my ATtiny45 and put it on my plane so I could get the temperature from above. Only problem is I have no way of seeing it. So is there a simple, easy solution to storing a couple of numbers? I though I could just set the temperature every 3 minutes to a variable, but if I turned the board off, the data would be lost. So I don't need to store tons of memory just a couple numbers! Thanks!

Topic by HavocRC   |  last reply


Small, simple LED project

I'm 3D printing a small translucent object that I'd like to light with a single LED. I'd prefer the assembly to be as small as possible, powered by a "watch battery" or two. It need not even have a switch; if the battery is in, it's on. It need not flash or be controllable in any other way. What electronic components do I need for something like this? Huge thanks! Jerry

Topic by jhatchett2   |  last reply


simple blinking LED switch?

I know little about how to make circuts and the like, so I come to intructables, wondering how to make something like this: You flip an on/off switch, and in stead of having the LED just stay constantly on, it starts to go on and off about once a second.(Half a second on, half a second off) If that made any scene, please answe

Topic by Bradley1000 


Simple, Illustrator CS3 Question ? Answered

Hello, Can anyone help me please with this simple Illustrator CS3  question. I am OK with Photoshop but am just trying Illustrator which seems a bit tricky by comparison. I want to take a black and white  jpg image and convert it to a vector image. From what I have gathered from numerous tutorials, I have to - Copy my image from PS and paste it into Illustrator: Then select the image. At this point the tutorials say that a LIvetrace button should appear along the top; it doesn't, but I can access Livetrace by going to object- Livetrace- options ( this only works when the object is not selected; if its selected everything is greyed out) Anyhoo, when I do get the dialogue box, the blue button that should say "trace" says "set  default". I did manage to get this to work with one image but I don't know what was different. I realise how long winded that explanation was; if you have got this far do you have any advice ? Thank you.

Question by FriendOfHumanity   |  last reply