Build Definition and 466 Threads

How to build a DC-->AC converter using resistors capacitors and diodes (no inductors) I have been trying to learn electronics (I am familiar with the principles, just have no experience designing complex circuits to fulfill purposes), so I went to RadioShack, got myself: breadboard assorted...

I want to build a thermistor or temperature detector that would shut down the system if over heated. Could someone post the step by step process to do so. Cheapest one possible.

I came home from a vacation to find my computer conpletely dead, I am assuming it's lightning from major storms that rocked south ontario last week. I have noticed that I have deposits of copper sulfate on my copper heat sink and cpu cooler made by zalman. I am wondering what would cause...

Hello geeks of PF! Wooooo! I am in need of some help that will allow me to build a device. Roughly this is how I want my device to work - This device will help notify users about anything that I would like to notify them by indicating it through an LED. The device has got 2 ends; one...

Is it possible to build a large mirror array (around 10 km²) with adjustable focal length (from 10 meters to around 400 kilometers)?

Hi everyone . How we can build a scheme for short circuit transformer in secondary and open circuit during transitional processes with Matlab/Simulink ? And how we can build a measurement for fluxes ??

I want to start an electronic company, but I don't know what are all the types of engineering jobs that are capable to build an electronic device (Ex: Cell Phone, Tablet). When I get to University, I'm planning to make some friends who have a degree on it. Also, I need to know what the jobs...

Hey PF! Short First Post Intro: I've been a long time spectator here. I'm a junior undergrad physics major. PF has been a lot of fun, and tremendous help to me (like last winter I applied to many REU's). So thank you all! At the REU I'm in now, I'm learning linux. I'd love to hear any of...

Hello All, I am trying to build what is essentially an electrochemical cell which I will use to filter waste water and try to recover gold silver and copper among other metals on a High Surface Area Cathode like Carbon.I want this electronic filter to be selective about the metals recovered...

Hello, I'm an undergraduate student, doing an independent research project under a professor this summer. So the experiment I am working on involves using a glow discharge tube, with electrodes at two ends, to create and contain a plasma column. The purpose is to measure and analyze "wave...

hi all, i am looking to build an ultrasound producing device that emits at 50,000 cps? i need a list of materials and how to construct the circuit. research shows that you can multiply the growth of plants (radishes were tested) by 150% if subjected to ultrsound at around 50,000 cps. thank you...

pdracer.com Three sheets of plywood and a couple sticks of lumber. Some titebond II, a tarp, and you have a sail boat. From personal experience I can tell you that these things sail upwind great, even in very little wind (as long as you sit back on the rocker and know how to sail upwind...

Which languages are required to build a firefox addon...? Which languages are required to build a firefox addon...?

Hello Everybody, I am going to build an optical lab. to characterize semiconductors which have a luminescence over a wide range 200 nm - 1500 nm. I hope to have a setup which flexible to carry more than spectroscopic technique and be able to study this wide spectral range. I would...

Okay, I'm no engineer, but I'm in need of some! I'm looking to build a type of cable system, and not even sure where to begin. Basically, the systems purpose is to carry a single bucket slowly back and forth from one side, back to the other. Think of a ski lift, on a flat plane, using only...

Can I build a resistojet? How? I am in tenth grade and I want to make it for Science Fair. A resistojet takes a non-reactive fluid, heats it up using a filament and electricity. The fluid is heated and shot out of a nozzle. Can something like this be built? Can you guys give me some advice...

I'm finally biting the bullet and have decided to build a bit of an overkill workstation. Goals: reduce down time for rendering and FEA calculations. I spent some time trying to research the right components and wow did that give me a bit of a headache! A lot seems to be geared towards the...

I need to build a micro pancake DC Motor. I actually need 32 of them connected in a line with one power supply. The motors need to be about the size of a dime. Could someone write me a how to guide on how this can be done. It is for a prototype.

Has anyone built a hydrogen cell using nafion?

In physics we have about a week to come with a design and build a machine to stop the egg from breaking. It will be launched from the third story We only can use the materials the teacher ( about 100 straws and a meter of tape) THATS ALL WE GET! The sraws bend a little but are not very...

So, my goal is to be able to take two walkie talkies and put one of them on a near space balloon and have a microcontroller send data through the walkie talkie on the balloon down to the one on earth. I'm not sure it would reach all the way back to Earth so I thought of putting a small linear...

Firstly, I spoke to a Physics teacher and some strangers on the internet as well as Googled and this is the situation I am in now. I want to build a software simulation for school of a damped-oscillation non-zero charged metallic-sphere pendulum within the uniform electric field of a...

hey i have a 5W pv panel and was wondering if i could build some sort of circuit to run my pool pump? was wondering what i would need ... any thoughts would be appreciated

More than 50 years after the invention of the laser, scientists at Yale University have built the world's first anti-laser, in which incoming beams of light interfere with one another in such a way as to perfectly cancel each other out. The discovery could pave the way for a number of novel...

I need to build an electromagnet that is able to pick up 8 ounces from 2-3 inches below it. the tuna cans are magnetic and are full of tuna. I have limited funds but have a lot of wire and stuff at home. the electromagnet will be powered at approx. 7.4 volts. i would like the electromagnet to be...

Hi, I'm trying to write a C program to build an ellipse given 3 points and the focus equals to (0,0); can someone help me out? Regards, CPtolemy

I'm currently studying A-Levels (Physics, Mathematics, and Further Mathematics) and will be applying to university [UK] next year. I love the idea of building and designing spacecraft s and I want to get involved in researches/experiments that will advance our current space travel...

I am trying to put together an inductive proximity detector for Rail Wheel detection. Currently we use an oscillator connected to a coil. We then count pulses on the oscillator and measure a detect when coil saturation changes the pulse. There are similar industries that use NAMUR...

-Non-gaming -Academic/commercial use (matlab, mathematica, autocad etc) -Emphasis on multi-monitor capability CPU: Intel Core i5-760 Lynnfield 2.8GHz MOBO: GIGABYTE GA-P55-USB3 LGA 1156 Case: Antec Dark Fleet DF-10 Black SECC ATX Mid Tower RAM: G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM...

Does anyone know the ISBN of a good textbook that goes into VERY deep details to build a zoom capable IR scope. Also the scope would have to give contrast such as show trees and other things that don't give off IR so that you are not just viewing a silouette of something in a blank frame.

As I have mentioned in this thread, it's that time of decade where I'm looking to build a new computer for myself. I'm hoping to not spend more than $800 CAD on the motherboard, processor and RAM but I have no real budgetary limit. Of course, I'm looking to optimize for some metric of...

Due to a major setbacks involving illness, I missed out on my junior year. I simply don't have the funding to continue waiting to take the necessary classes and so at this point I just need any degree (lest these past four years be all for naught.) I have 130 credits, roughly 45-50 in math...

Homework Statement To build a triangular pile consisting of 120 balls, the number of balls in the base would have to be?? Multiple Choice a. 24 b. 30 c. 36 d. 45 Homework Equations The Attempt at a Solution The answer is 36. How do I get this answer and is...

Hire Chinese contractors. https://www.youtube.com/watch?v=Ps0DSihggio&feature=player_embedded#!

Here's what the plan is I need a dyno for a new engine development program. small displacement engines, 50cc some day up to 200cc+. I need comparative data engine to engine, tuning, proto components, etc.. this is all diy budget stuff please keep this in mind. I come from automotive and race...

Im not sure where to post this thread, so its ok if you move it. But anyways, for extra credit in physics ( and i need these points really bad) we have to create a balloon powered vehicle. In other words as air is released from the balloon, it propels the vehicle forward. I need mine to go the...

This thread is for those of us who either don't do gaming, or who do some decent, but not high-end gaming, and would simply prefer to upgrade or build our own systems. Please do include links to reviews and online parts in your posts (although not 20 links per post, please, yech!). Please...

Hey everyone, Well, I want to build my first robot, and for learning reasons I thought I would pick up a robot kit. Is that a good idea? Any tips for someone who wants to build their first robot, and get there feet wet? I have NO experience building robots, but its always been a passion...

Homework Statement A mass M is hauled from ground level up an inclined plane that makes an angle 0 with the horizontal by means of a rope passing over a frictionless pulley. The mass is pulled along until it reaches a height of H. The building of the Egyptian pyramids and many other ancient...

I think it is due to friction and the carnot efficiency is derived in a reversible cycle. Also,can i build just a little bit irreversible but still carnot? But if irreversible how can i draw the graph? Still smooth line?

What is the difference between static attraction or repelling, compared to magnetic. I understand the princips of static build up and why a charged positive and charged negative attract each other. I also understand how the atoms are arranged in a "metal-magnet". But why can't you attract a...

Hi everyone, I am currently doing a project with a group of friends. The project requires us to build a palm reader which uses electrodes to read the hand's impedance and then do the things that the circuit was designed to do. My group's idea is to build a piano. We use the electrodes as...

Hey guys, I'm new to this forum and I've been meaning to start a project of my own. I want to create a homemade battery that gives me the highest voltage and current I can have using only two-three metals and an electrolytic solution. It can only be easily accessed metals, as I live in a city...

Basically as the title says, is it possible to build a DB fuel cell stack? Something that could output 100W (to power a laptop or for power outages). I actually have access to a couple of kilos of sodium borohydride and while looking at what I can do with the stuff I came across this type of...

No rules besides u cannot use a shopping cart,bicyle to build off of and u cannot use a motor or pedals with chain. I am going to use bicycle wheels. 2 rear and one front. where should i go from here? Anything goes really. ill post some pics from the past cpl years of what people did...

hi, i am pretty new with electronics, and i can't find any simple boost converter circuts on the enternet. i would like to make the circut THE MOST SIMPLE i can, with the fewest possible parts. for a power source, i have 9v-1w. for the output power, i would like to send a thin spark from 1...

Okay so in my brain, I want to do something that's like BAM! Makes people want to do it themselves instead of watching T.V want to get out and be like, if he could make that, what's stopping me from doing [random thing they've always wanted to do]. What i want to do is build a flying machine...

Hey guys, I'm trying to do some experiments at low temperatures in my garage. I have an air compressor that can push 6 cfm at 150 psi, and I want to expand this gas through an isentropic expander (NOT an isenthalpic expansion valve). Isentropic expansion extracts work from the fluid as it...

How to make a DIY laser cutter(small size) ? Can you help me?

Sorry if there is already a thread for this. But what are all the different types of EE and with each specialization what are things you can make and what kind of things do you guys make on your own at home