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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.

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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. 101 - 200 Transistor Circuits e-book. It contains a further 100 circuits, with many of them containing one or more Integrated Circuits (ICs). It's amazing what you can do with transistors but when Integrated Circuits came along, the whole field of electronics exploded. IC's can handle both analogue as well as digital signals but before their arrival, nearly all circuits were analogue or very simple "digital" switching circuits. Let's explain what we mean. The word analogue is a waveform or signal that is changing (increasing and decreasing) at a constant or non constant rate.

The Transistor Lists of Nobel Prizes and Laureates The Transistor Play the Transistor Recycler Game About the game A transistor is made of a solid piece of a semiconductor material and either used as switches, to turn electronic signals on or off – or, as amplifiers. 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.

Passive filter circuits : Worksheet Question 1: In very simple, qualitative terms, rate the impedance of capacitors and inductors as ßeen" by low-frequency and high-frequency signals alike: Capacitor as it äppears" to a low frequency signal: (high or low) impedance? 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

Electrcity: History & Science © Matthew Modoono Indoor bolts produced by the world's largest air-insulated Van de Graaff generator spark exciting explorations of lightning, conductors, insulators, electricity, magnetism, and storm safety. Seating is first come, first served. Now Showing Operational amplifier applications This article illustrates some typical applications of operational amplifiers. A simplified schematic notation is used, and the reader is reminded that many details such as device selection and power supply connections are not shown. Operational amplifiers are optimised for use with negative feedback, and this article discusses only negative-feedback applications. LC meter, Coil Capacitor meter This LC meter circuit can measure coils and capacitors. When Lx or Cx is connected in the circuit the oscillator frequency will decrease and this decrease is measured by a frequency-voltage converter build with T3 and T4. To adjust this lc meter circuit with P1 and P2. LC meter precision is 3%. Scale calibration can be achieved with this formula: ni = nm(1 – fr)/(1 – fc) where ni is number of divisions measured on the scale, nm = total number of division of the scale, fr = relative frequency, fc = the smallest relative frequency measured. The total power consumption is 12mA at 12V when the LC measurement occur.

b e a . s t [an error occurred while processing this directive] Magnetic Levitation using Hall effect Sensor Feedback, and Matched resonant wireless power transfer This work was completed initially for a final project for Joe Paradiso's class MAS.836 - Sensor systems for Interactive Environments, taken Spring 2oo5. Click to watch the following movies:Magnet Levitation Movie [100 megs], or in Small form. Electronics Demonstrations BasicsA/C CircuitsPassive FiltersOther Passive CircuitsDiodesOp-AmpsMOSFETsTransistors (Bipolar)Combinational LogicSequential Logic555 Timer ChipTransmission LinesMemristorsTunnel DiodesSpark Gaps

pH measurement : ELECTRICAL INSTRUMENTATION SIGNALS A very important measurement in many liquid chemical processes (industrial, pharmaceutical, manufacturing, food production, etc.) is that of pH: the measurement of hydrogen ion concentration in a liquid solution. A solution with a low pH value is called an "acid," while one with a high pH is called a "caustic." The common pH scale extends from 0 (strong acid) to 14 (strong caustic), with 7 in the middle representing pure water (neutral): pH is defined as follows: the lower-case letter "p" in pH stands for the negative common (base ten) logarithm, while the upper-case letter "H" stands for the element hydrogen.

Tutorials The most fun you can have (after blinking LEDs) is using sensors to detect whats going on in the world and act on that information. However, all sensors have their own methods of interfacing. That can make them a real pain to work with: some need pull-up resistors, some need certain power supplies, some use lots of power, some don't. Since there aren't that many different sensors that people tend to want to use I have collected the most common sensors with code examples and wiring diagrams. Tutorials include: Force sensitive resistor - Used to detect physical pressure such as pinching, squeezing, pushing, brushing. Photocells - Used to detect light/dark, breakbeams, simple object detection.

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