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Hobby projects - Simple electronic circuits

Computer microphones Learn how to interface electret and dynamic microphones to the standard computer sound card. Metal detectors Theory of operation and schematics of the most common metal detectors used today: Very Low Frequency (VLF), Pulse Induction (PI) and Beat-Frequency Oscillator (BFO). Wireless microphone The wireless microphone transmitter can be built in an afternoon with simple, affordable and widely available parts. Related:  Electronic Circuits

eCircuit Center Mike's Electric Stuff ABCelectronique, portail de l'électronique Handbook of hardware pinouts, cables schemes and connectors layouts Circuit Simulator Applet This is an electronic circuit simulator. When the applet starts up you will see an animated schematic of a simple LRC circuit. The green color indicates positive voltage. To turn a switch on or off, just click on it. The "Circuits" menu contains a lot of sample circuits for you to try. Full Screen version. Directions. Index of Circuit Examples. More applets. Javascript version. Report a problem/feature request Huge thanks to Iain Sharp for the Javascript port. java@falstad.com

AVR projects and AVR Butterfly gcc port by Martin THOMAS G.d.W. SS2010 FHFFM You may like to visit my ARM-Projects page too (projects and information for NXP LPC2000, Atmel AT91SAM7, STmicro STR7, STM32, LMI LM3S and other controllers with an ARM-core). Last update in the ARM-section: 25. Available Projects and Information (Content) "Last updated" may be just additional information not always a new version of a software-package. AVR Butterfly Application code port to avr-gcc Introduction The AVR Butterfly (ATAVRBFLY) made by ATMEL comes with a preloaded application. For german readers: Der Quellcode der auf dem AVR-Butterfly installierten Applikation wird von ATMEL für den IAR C-Compiler zum Download bereitgestellt. Even if you do not own an AVR Butterfly you may find usefull information in the BF application code for general ATMEL AVR development tasks. From the gcc-port of the application code some methodes how to convert IAR-code to avr-gcc/avr-libc-code can be learned. Butterfly gcc-port history Software 2.Oct.2003 - 4.

Réalisations - Alim. led Electronique > Réalisations > Alimentations > Alimentation d'une LED Dernière mise à jour : 06/03/2016 Présentation Les lignes qui suivent décrivent comment utiliser une LED de façon isolée ou en groupe, avec des tensions alternatives ou continues. Pour plus de renseignements concernant ce composant, merci de vous reporter à la page Théorie - LED. Bases - Alimentation en basse tension continue Une LED, si on l'alimente directement et sans autre forme de procès à une source de tension continue (pile 9 V neuve par exemple) ou à une source de tension alternative (secondaire d'un transformateur 220V / 9V par exemple), a 99% de chances de griller. Sur le schéma qui précède, la valeur de la résistance R1 est donnée à titre indicatif, la tension V n'étant pas spécifiée. La LED utilisée pour les deux expériences qui suivent est une LED verte fonctionnant de façon nominale avec une tension de 2,2 V et un courant de 20 mA. Valeurs typiques de tensions et courants pour quelques LED Remarques Oulà !

How-To: Make a solid-state A/V switcher Ben's Solid State A/V Switcher. Comes in any color you'd like as long as it's black. As you probably recall we recently had several articles on the Wii laptop which, of course, has Virtual Console game emulation. But what about people who'd prefer to have, say, every system they own hooked up all at once to one TV? Or a full-featured standalone DVD player and an Xbox 360, both using component video? While "solid state" may bring bring to mind electronics from the 60s (or, in some cases, yet-unreleased flash hard drives), but in this case it simply means the actual switching is done with circuitry, not mechanically. In this How-To we'll show you how to wire up your own A/V switcher which you can expand and use any way you'd like, for composite, S-Sideo, component, even VGA signals. For this project's example we'll be building a 3 input, single output composite video, left / right audio switcher. Parts list Here's the electronics we'll need to build this project. Other things you'll need:

Electronic Circuits on Circuit Exchange International (CXI) Build the BASIC SPY TRANSMITTER - Page 1 of 16 Build the 2 transistor Spy Transmitter Radio frequency projects can seem more difficult than most electronics projects because most of the time you cannot build them on a solderless breadboard and there may be parts used that are not easy to source such as coils and adjustable capacitors. This project is focused towards those who have not yet attempted to build any kind of RF project, and it is laid out in such a way as to make it easy to explore the basic principles of RF circuitry and ensure a successful final product. This simple 2 transistor audio transmitter will send the sounds picked up in a room to any FM radio tuned to the same frequency as the transmitter, somewhere between 80 and 100 Megahertz. Figure 1 - You can salvage most of the parts needed from an old radio Since many of the parts only need to be "close enough", you will probably be able to salvage all that you need from any old radio, TV, or RF based circuit board. You are Viewing...

Motors and Microcontrollers 101 Electric motors are a key way of converting electrical power (voltage and current) into mechanical power (torque and speed), and because electric motors are simple and reliable machines, they can be found all over, in many different shapes and sizes. Just considering a normal (gasoline-powered) car, there are a great number of electric motors: the powerful starter motor and alternatoralternating windshield wiper motorsintermittent-use power windows and door locksthe blower fan that moves hot and cold air into the cabinthe tiny motors inside the CD player And I'm sure you can think of others. While a full analysis would have to look simultaneously at the motor and the attached mechanical system, in this video tutorial we're just going to address the electrical side of the system. Here are some photos and drawings related to the video (click to enlarge): Our final motor control circuit looks like this: Spinning the motor makes a voltage. Go give them a try! Maximum forward current.

Transformers In the photograph, note that the coil on the left has fewer coils than that at right (the insets show close-ups). The sketch and circuit show a step-up transformer. To make a step-down transformer, one only has to put the source on the right and the load on the left. (Important safety note: for a real transformer, you could only 'plug it in backwards' only after verifying that the voltage rating were appropriate.) So, how does s transformer work? The core (shaded) has high magnetic permeability (ie a material that forms a magnetic field much more easily than free space does, due to the orientation of atomic dipoles). Vp = − Np.dφ/dt . VpIp = VsIs, whence Is/Ip = Np/Ns = 1/r. So you don't get something for nothing: if you increase the voltage, you decrease the current by at least the same factor. In some cases, decreasing the current is the aim of the exercise.

Jones on Stepping Motor Types - Мозилин фајерфокс (Mozilla Firefox) Introduction Stepping motors come in two varieties, permanent magnet and variable reluctance (there are also hybrid motors, which are indistinguishable from permanent magnet motors from the controller's point of view). Lacking a label on the motor, you can generally tell the two apart by feel when no power is applied. Stepping motors come in a wide range of angular resolution. For both permanent magnet and variable reluctance stepping motors, if just one winding of the motor is energised, the rotor (under no load) will snap to a fixed angle and then hold that angle until the torque exceeds the holding torque of the motor, at which point, the rotor will turn, trying to hold at each successive equilibrium point. Variable Reluctance Motors Figure 1.1 The cross section shown in Figure 1.1 is of 30 degree per step variable reluctance motor. To rotate this motor continuously, we just apply power to the 3 windings in sequence. Unipolar Motors Figure 1.2 Bipolar Motors Figure 1.3 Bifilar Motors

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