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How to Make a Crystal Radio in 10 Minutes

How to Make a Crystal Radio in 10 Minutes

How to Build a Robot Tutorial - Society of Robots Introduction to Gears No good robot can ever be built without gears. As such, a good understanding of how gears affect parameters such as torque and velocity are very important. In this tutorial I will first talk about the basics of gears, how to use them properly along with simple equations, and then I will go into specific types of gears. Mechanical Advantage, Torque vs. As with all motors, by looking at the motor datasheet you can determine the output velocity and torque of your motor. With gears, you will exchange the high velocity with a better torque. Torque_Old * Velocity_Old = Torque_New * Velocity_New Torque_Old and Velocity_Old can be found simply by looking up the datasheet of your motor. So for example, suppose your motor outputs 3 lb-in torque at 2000rps according to the datasheet, but you only want 300rps. 3 lb-in * 2000rps = Torque_New * 300rps With highschool algebra you can then determine that your new torque will be 20 lb-in. 3 lb-in * 2000rps = 5 lb-in * Velocity_New

Build Your Own Server | Why pay somebody to do it for you when you can build it yourself! [global] panic action = /usr/share/samba/panic-action %d workgroup = "Name" netbios name = "Server name" invalid users = root security = user wins support = no log file = /var/log/samba.log log level = 3 max log size = 1000 syslog = 1 encrypt passwords = true passdb backend = smbpasswd socket options = TCP_NODELAY dns proxy = no passwd program = /usr/bin/passwd %u passwd chat =*Enter\snew\sUNIX\spassword:* %n\n *Retype\snew\sUNIX\spassword:* %n\n . obey pam restrictions = yes pam password change = no null passwords = no #Share Definitions [homes] comment = Home Directories browseable = yes writable = yes security mask = 0700 create mask = 0700 #!/bin/sh x11vnc -nap -bg -many -rfbauth ~/.vnc/passwd -desktop "VNC ${USER}@${HOSTNAME}" \ |grep -Eo "[0-9]{4}">~/.vnc/port

DIY Stereolithography 3D Printer Build a Laser 3D Printer - Stereolithography at Home Here is how to make a Stereolithography 3D Printer. It is still a bit of a work in progress but so far it is working pretty well. This is mainly an experiment which started as a Delta Robot Stereolithography Printer but ended as a more traditional Cartesian Stereolithography Printer. "I'll be honest, we're throwing science at the walls here to see what sticks. Stereolithography (SL or SLA from Stereolithography Apparatus) is an additive manufacturing process using a vat of liquid UV-curable photopolymer "resin" and a UV laser to build parts one layer at a time. I have wanted a 3D Printer for a while now and there are some very reasonably priced kits available like the Makerbot, Ultimaker and the RepRap project. I decided to enter this in the Epilog Challenge Contest because I could really use a laser cutter :-) I also have some ideas how to redesign this project, for creation on a laser cutter. This project is Open Source Hardware.

How to Make a Three-Pendulum Rotary Harmonograph A harmonograph is a mechanical device that uses swinging pendulums to draw pictures, believed to be originally invented in 1844 by Scottish mathematician Hugh Blackburn. This 3-pendulum rotary type of harmonograph gives a wide variety of pleasant results, and is fairly easy to build once you've settled on a design and have acquired the appropriate materials and tools. This is a great project to do with kids and can result in endless experiments creating new types of geometric designs. Skip to More Results and Movie Two lateral pendulums swing back and forth at right angles to each other with arms connecting to a pen. One moves the pen from side to side, and the second moves it from front to back on the paper. A third "rotary" pendulum moves the paper by swinging on any axis or in circular motions, while the pen is drawing on it.

Lesson Plan for Making a Speaker Laboratory ©1995 The Regents of the University of California by Regan Lum Introduction: A speaker is a device that converts an electronic signal into sound. The speaker you will build (see figure 1) consists of a Styrofoam or paper cup, a coil of wire, a permanent magnet, and a signal source. The electronic signal goes through the coil and creates a varying electromagnet. figure 1 Purpose: In this laboratory, you will explore how a speaker works. Materials: 1 permanent magnet 2 feet of wire 1 pencil tape or glue 1 Styrofoam or paper cup 1 signal source (tape player) 1 plug with alligator clips for tape player Procedure: Assemble material as shown in figure 1. Leaving about 10 centimeters on the end, wrap the wire around a pencil to make a wire coil and tape or glue it to the bottom of the cup. Conclusion Does the volume control on the tape player work on your speaker? Return to CEA Science Education Home Page

Electronic Projects For Beginners I made a guide for those people who are still starting with their electronics hobby. I started connecting wires, batteries, bulbs, buzzers and motors when I was 4 years old . Now that I am 13 years old, I now have a good amount of experience to build complicated electronic circuits. It took me hours to finish making this guide since there is no software editor in the Sibmit>Guide in the "Submit Instructable Section" I had to type every word and picture using HTML codes which I learned from school. These are my all time favorite projects in instructables, I find them simple and easy to make. How To Solder by: noahw Third Hand by: rstraught Making A Customized Circuit Board by: ASCAS How I built a Solar iPhone Charger ($50) by: akbrennan Make a USB iPhone iPod Charger On The Cheap! Build a Simple Circuit from a Pizza Box (No Soldering) by: matt.e.jenkins Solar Cockroach Virbobot by: JoshuaZimmerman Water Powered Calculator (Original) by: ASCAS Munny Speakers by: fungus amungus

Top 10 DIY Tech Gifts @keyboard-vomit: Yeah, but wouldn't it be awesome if some of our not so tech friends actually attempted (and accomplished) one or more of these feats? I mean, when "it's the thought that counts," shouldn't it be a thought about something we'd actually appreciate. Then again, maybe socks are your thing. ;) @HunterShoptaw: That they are, I'm wanting some socks with an integrated HDD, and some USB connectivity. @HunterShoptaw: The thought does count, but it sure would be nice if they enjoyed the gift too. So for this year, I created wishgenies dot com for people who WANT to give good gifts, but don't know what they'll want. @keyboard-vomit: I swear that some day, some how...Google will be able to find my lost socks.

Top 10 Things You Can Upgrade with a Little Electronics Hacking it is a skill to do a good solder joint, it comes with LOTS of practice. so most people who rarely do it will ever get good at it. Bingo. Of course, part of the issue is having a soldering iron at the right temp with a properly tinned tip. Newbies aren't using soldering stations but a cheap iron they got at rat shack (You have questions? We have deer-in-the-headlights... erm... answers!). I don't expect to ever master tricky stuff like smts or even multilayer pcbs so I'm not much better then a newbie, anyway - and I totally suck at sweating pipe joints. Ah, well... SMT is actually a bit better than through-hole once you get the hang of it.

DIY Polygraph Machine: Detect Lies with Tin Foil, Wire and Arduino DIY Polygraph Machine: Detect Lies with Tin Foil, Wire and Arduino Lying is awesome. From a very young age, children learn that flat out denying the truth gets you out of trouble and helps keep you calm in the face of horror. But what happens when you just have to know if someone, say, used your toothbrush? You could ask them to take an expensive and arduous polygraph test. If you're industrious and don't have the dough for a legit polygraph, you can make your very own galvanic skin response (GSR) device. Today, we will make a cheap GSR device and learn if our toothbrush is really safe after all. Materials ArduinoAluminum foilVelcroWire10k resistorBreadboard Step 1 Make the Electrodes GSR machines require an even and consistent connection to the skin in order to function properly. Begin by taping the exposed end of a wires to a sheet of foil. Adhere a strip of Velcro over the tape and cut off the extra foil. Last, add a single piece of Velcro at the end of the foil side. Step 3 Load the Code

How to Make Char-Twine How to make Char Cord / Char Rope Build a Touchless 3D Tracking Interface with Everyday Materials Combine low-tech materials with some high-tech components and build a completely Touchless 3D Tracking Interface. Explore capacitive sensing by using several panels of cardboard lined with aluminum foil. These panels, when charged, create electric fields that correspond to X, Y, and Z axes to create a 3D cube. For Weekend Projects makers looking for an introduction to Arduino, this is a great project to learn from. Once your touchless 3D tracker is up and running, what you do with it is only limited by your own imagination! Make an RGB or HSB color pickerControl video or music parameters; sequence a beat or melodyLarge, slightly bent surface with multiple plates + a projector = “Minority Report” interface Sign up below for the Weekend Projects Newsletter to receive the projects before anybody else does, get tips, see other makers’ builds, and more. More: See all of the Weekend Projects posts Related

How to make a tool set Life without tools is barbaric. But even simple tools can be expensive in rural parts of developing countries. Import duties bump the costs up higher than they are in the States or elsewhere, and sometimes only low-quality brands are available anyway. So, to hold off future barbarians, we'd like to show how to build a simple tool set on a very low budget. Larry Bentley, the man who figured out how to make these tools, said a wise thing: "Without tools, kids don't take stuff apart, and without taking stuff apart, you don't learn how things work." These tools, Bentley says, could be in the hands of the next William Kamkambwa,who made a working wind power generator from backyard scraps in a village in Malawi. Here's Larry's quick guide to DIY tools. The tools in this guide: Saw Pliers Wooden vice Wood drill bit / star drill bit Chisel Strap hinge vice

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