Electronics Circuits
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Operational amplifier applications - Wikipedia, the free encyclopedia
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. It is important to note that the equations shown below, pertaining to each type of circuit, assume that an ideal op amp is used.Hobby projects - Simple electronic circuits
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). The wireless microphone transmitter can be built in an afternoon with simple, affordable and widely available parts. Take care with transmitter circuits. It is illegal in most countries to operate radio transmitters without a license. But the output power of this circuit is below the legal limits of many countries (e.g., USA and Australia).
Electronics Demonstrations
Electronics Demonstrations The following demonstrations use a java applet that simulates electronic circuits. Click on the " Resistors " example for a brief summary of how the applet works. Or you can use the full applet .
Circuit Simulator Applet
This java applet 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.
555 Timer Tutorials
The LM122 series are precision timers that offer great versatility with high accuracy. They operate with unregulated supplies from 4.5V to 40V while maintaining constant timing periods from microseconds to hours. Internal logic and regulator circuits complement the basic timing function enabling the LM122 series to operate in many different applications with a minimum of external components.Freaklabs - Open Source Wireless - Feeding the Shark - Turning the Freakduino into a Realtime Wireless Protocol Analyzer with Wireshark
One of the most powerful tools to have when doing any type of design that involves communication protocols is a protocol analyzer. It allows you to see exactly what the communicating devices are seeing which is very useful for troubleshooting many types of problems that might come up. This is especially important for wireless communications because this is often the only way to see what type of data is going over the air. It also allows the user to see if there are any rogue frames, check for breaches of the communication protocol, analyze traffic, or reverse engineer a proprietary protocol.
RF Communication Between Microcontrollers – Part I | eXtreme Electronics
In many situations a communication link between to devices becomes essential. This communication can be wired or wireless. If two devices are close to each other (like a MCU and a Memory) a wired link is preferred. How ever in many situations two devices are reasonably far apart.
www.electricstuff.co.uk Each of the three main sections has a 'tour' facility for easier navigation through the pages - clicking on the small icons at the corners of each page will move to the next or previous page in that section. Warning! Tesla coils and their ancillary equipment are VERY VERY dangerous and you should not even THINK about trying to make one unless you really understand the dangers of high-voltage electrical systems.
Mike's Electric Stuff
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.
A Sine Wave Generator
One type of signal that is in frequent demand is the sine wave. Of course, we could use an op amp in place of a transistor as the gain element in a Wien Bridge oscillator or a Twin-T oscillator, but they have a problem with requiring multiple capacitors and resistors in some odd configurations for setting the frequency of oscillation. Can we do something with analog integrators and inverters to obtain the same result? The circuit to the right implements the mathematical relationship between the sine and cosine trigonometric functions.
The hybrid pi model of a BJT is a small signal model, named after the “ p ”-like equivalent circuit for a bipolar junction transistor. The model is shown in Figure 5.6.1 . It consists of an input impedance, r p , an output impedance r 0 , and a voltage controlled current source described by the transconductance, g m .
Bipolar Junction Transistors
AVR projects and AVR Butterfly gcc port
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: 8. July 2010. The AVR Butterfly (ATAVRBFLY) made by ATMEL comes with a preloaded application. The application source-code can be downloaded from the ATMEL Web-Site ( AVR Butterfly - Application Rev07 ).Bipolar junction transistors as switches : Worksheet
Question 1: Solid-state switching circuits usually keep their constituent transistors in one of two modes: cutoff or saturation . Explain what each of these terms means. Reveal Answer "Cutoff" refers to that condition where a transistor is not conducting any collector current (it is fully off).Capacitor Voltage Change
This curve fitted equation can then be used in LTSpice to model the Y5U capacitor, with its capacitance versus voltage relationship. To model a non-linear capacitance in LTSpice, it's necessary to write an equation relating charge (in Coulombs) versus bias voltage. This mathmatical relationship is written into the value of the capacitor (instead of so many uF or pF) as Q=f(x) where X is the pre-defined variable in LTspice representing the instantaneous voltage across the capacitor. C(V) is the relationship between capacitance and applied voltage, in this case, as determined by our 7th order polynomial fitted to the measured C versus V data: In a theoretically perfect capacitor of constant value, of course, the relationship between charge and voltage is simple; Q=CV where Q is the charge in Coulombs, C is the capacitance in Farads and V is the voltage in Volts. This is the case since the integral from 0 to V of CdV is simply CV.PSPICE Circuit Simulation