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How to Make a Crystal Radio in 10 Minutes

How to Make a Crystal Radio in 10 Minutes
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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

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

What 5 Things can You Do to Change the System? | The Overthinker A few weeks ago a reader on this blog asked me an interesting question that I have been mulling over for some while: can I list 5 things everyone needs to do to change the system? It’s a tall order, but I decided to give it a bash. I don’t plan to prescribe anything here, and no one should take my word for it as I’m no paragon of purism. But I have at least dabbled in all that I will suggest, and would like to invite dialogue around those suggestions, and others. One glaring problem stares me down: how can we change the system when we don’t have the power? I figured my response should not just be things everyone should do, but things everyone can do – at least to some extent – and can scale up. I don’t think in those mechanistic, reductionist terms whereby every problem can be pared down to its constituent parts, and each part can be tackled separately so that the whole picture, when you put it back together again, looks rosy. 1. This comes in a series of steps. 2. 3. 4. 5.

Standard Grade Bitesize French - Talking about yourself : Revision 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

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

DMT: The Spirit Molecule How to Improve Your Drawing Skills | Disappointed by your doodles, and wish you could draw better? Drawing well is about your hand being able to do what your brain tells it to do. And if your hand doesn’t have much practice at creating certain shapes or lines, the end result of your sketching may not look at all like it did in your mind’s eye. If you can hold a pencil or pen, you can expand your drawing skills by working on fun projects you'll enjoy!

DIY Stereolithography 3D Printer 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.

How To YouTube Your Way to Van Gogh Level Skillz Whether you’re getting your bachelor’s degree in painting, graphic design or sculpture, there’s so much to learn about art — from its lush history to materials — that it can sometimes feel overwhelming. Yet art students shouldn’t fret. There’s a whole lifetime ahead to learn and numerous resources both in the classroom and outside of it for expanding your knowledge. One great place to seek out help with becoming a better artist is on YouTube. There, other artists, teachers and experts share their lessons on just about everything you could want to know. Drawing From how to sketch parts of the body to the best materials to use, these videos will help educate you on all things drawing-related. How to Draw a Realistic Eye: Eyes have been called the window to the soul, and if you want to create a realistic portrait you have to get them just right to give your drawing the emotion it needs. Painting Illustration Photography Graphic Design Sculpture Printmaking Comics

Web Resources To Improve Productivity 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 Char Cord / Char Rope