Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
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Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
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AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
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Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
New Circuits Page 41
80 milliwatt Improved 3 Transistor Audio Amp
This circuit is similar to the one above but uses positive feedback to get a little more amplitude to the speaker. I copied it from a small 5 transistor radio that uses a 25 ohm speaker. In the circuit above, the load resistor for the driver transistor is tied directly to the + supply. This has a disadvantage in that as the output moves positive,
We`ve already seen one example of a monostable multivibrator in use: the pulse detector used within the circuitry of flip-flops, to enable the latch portion for a brief time when the clock input signal transitions from either low to high or high to low. The pulse detector is classified as a monostable multivibrator because it has only one stable s
simple inductance meter
This article describes how to build a simple inductance meter. The PCB layout is included..
Ultrasonic signal range
audio notch filter
At first glance this circuit looks fairly complex, but when broken down, can be divided into high pass and low pass filter sections followed by a summing amplifier with a gain of around 20 times. Supply rail voltage is +/- 9V DC. The controls may also be adjusted for use as a band stop (notch) filter or band pass filter.
FM Radio project detailed here is based on SONY 1619 chip. This is single chip radio means, everything from Antenna to Speaker is done by Sony IC, specially designed for AM/FM Radios. Radio is designed on a double sided PTH Board and works on USB power. There is an option to add 6V battery (4xAA or AAA) but that is not part of the kit. USB power...
The Audionics CC-2 Amplifier
Although the Audionics CC-2 is named after Cliff Moulton (Audionics` chief engineer) and Charles Wood (Prez of Audionics), as usual in the business world, the principals in the company masked the identity of the real creator - Bob Sickler, whose name appears as "RLS" on the schematics. Since Bob passed away several years ago in Portland, the leas
Fundamentals of Electrical Engineering and Strain gauges
If a strip of conductive metal is stretched, it will become skinnier and longer, both changes resulting in an increase of electrical resistance end-to-end. Conversely, if a strip of conductive metal is placed under compressive force (without buckling), it will broaden and shorten. If these stresses are kept within the elastic limit of the metal...
interafce 16x2 lcd with avr
LCD comes in various configurations and the most popular one is 16x2 matrix display. This article shows the interfacing of ATmega16 with LCD by displaying a simple character on the LCD. In this project LCD is working in 8-bit mode i. e. , the data transferred to the LCD must be in 8-bit data form. The PortA of ATmega16 is connected to data pins...
Structural analysis of switching power supply
Daily switching power supply, mainly offer the direct current power supply for electronic device and supply power. The required direct-current volts of the electronic device, ranges are generally all between several volts and more than ten volts, and the voltage of exchanging Piower supply of city power is 220V 110V, The frequency is 50Hz 60Hz. T
Circuit Diagram Wiring
This Bat Detector Circuit is authored by Chris Eve. Basic tests with a variety of salvaged electret microphones all showed good response to 50kHz and beyond, the smaller the unit the better the response. My tests indicate that a small electret microphone has at least some response to 100kHz and that this response is reasonably flat to at least
Low cost touch sensitive switch project
led bicycle lights
Before getting started an acknowledgement is due, the circuit presented here uses an ingenious method of controlling a flyback converter by the voltage developed on a cur-rent sensing resistor, this was published by Andrew Armstrong in the July 1992 issue of ETI magazine. The reworked circuit is quite simple. At the instant that power is applied o
lantern dimmer circuit
Here the circuit diagram of Lantern dimmer/flasher designed by Tony Van Roon: Electronic parts List: R1 = 100K R2 = 100K R3 = 100K R4 = 100K R5 = 3K9 R6 = 3K9 R7 = 470 R8 = 100 R9 = 220, 1/2 watt P1 = 5K C1, C3 = 10uF/16V C2 = 0. 01uF, ceramic T1. This simple 220V light dimmer circuit can be used to adjust the brightness of mains lights. It also ca
Car Battery Failure Detector
A car battery deteriorates in use and its life seldom exceeds four years. When new, its voltage may drop to only 2V while cranking the engine. As the battery ages, its internal impedance increases and so the voltage drop while cranking also increases, until ultimately the drop is high enough to prevent the engine from starting. This gradual increa
Light that screen!
The circuit being very simple, this project can be used as a first NXT hardware hack. A white LED (D1) is powered through a 150 ohm resistor (R1) by the 4. 3V NXT power supply. The threshold of white LEDs is about 3. 5V, so the current in the resistor will be about (4. 3V - 3. 5V) / 150ohm = 5mA. This current is low enough to avoid draining the
Music related schematics Circuits and Diagram
ultra low drop linear voltage regulator
This circuit is a Mosfet-based linear voltage regulator with a voltage drop of as low as 60mV at 1A. The circuit uses a 15V-0-15V transformer and employs an IRF540 N-channel Mosfet (Q1) to deliver the regulated 12V output. The gate drive voltage required for the Mosfet is generated using a voltage doubler circuit consisting of diodes D1 & D2 and c
5V transformer less power supply
Here is the circuit diagram of a 5V transformer less power supply using minimum components. The working of this circuit is quite simple. Resistor R1 does the job of current limiting and bridge D1 rectifies the mains voltage. The Zener diode regulates the rectifier output to obtain a steady 5V DC and capacitor C2 acts as a filter.
12V Powered 12V Lead Acid Battery Charger with Indicator
Some of you might wonder why a charger is needed at all, to charge a 12 Volt battery from a 12 Volt source! Well, firstly the "12 Volt" source will typically vary anywhere from 11 Volt to 15 Volt, and then a battery needs a controlled charge current and voltage, which cannot result from connecting it directly to a voltage source. The charger descr
keypad interfacing with 8051 slicker
Detector Components & Infrared Motion Work
Detector Components & Infrared Motion Work, Electronic Circuit Schematic Wiring Diagram, Detector Components & Infrared Motion Work.
LED Audio Level Meter Circuit Schematic Diagram
This circuit uses two quad op-amps to form an eight LED audio level meter. The op-amp used in this particular circuit is the LM324. It is a popular IC and should be available from many parts stores. The 1K resistors in the circuit are essential so that the LED`s turn on at different audio levels. There is no reason why you can`t change these resis
Simple 144 MHz RF Detector
This simple circuit helps you sniff out RF radiation leaking from your transmitter, improper joints, a broken cable or equipment with poor RF shielding. The tester is designed for the 2-m amateur radio band (144-146 MHz in Europe). The instrument has a 4-step LED readout and an audible alarm for high radiation voltages. The RF signal is picked up
DC to AC inverter H-Bridge
Hi everybody. I need H-bridge schematic for 230V 50Hz output from DC 350V, using 555 timer IC and mosfets..
LCD Frequency Counter Using PIC
Improve the response characteristic of USB 2.0 switching system
Square Wave Oscillator
This scheme applies amplifier OpAmp LM301 to awaken square wave that is simple. LM301 applies power allowance 3 V - 36 V, with highest frequency 325 kHzs. Oscillation frequency given in equation. where f is Hertz, R in Ohm, C in Farad. Active Pressure C1 have to be more a few 2/3 of power allowance tensions. At C1 stands to throw away charge. Input
Two Transistors Wireless Microphone FM Transmitter Circuit Schematic Diagram
pickit 2 download develop your own usb pickit ii programmer
PICkit 2 Introduction: There are many PIC programmer available, commercial and DIY devices. As Microchip introduces the new microprocessors the prog..
Triton Cooling Systems
The Lambda II is based upon the Atmel 8535 chip, which operates at 4 MHz and contains 8K of RAM. This chip was chosen over other brands such as Motorola or Pic, because the circuit used to program it using a computer is very simple to build. This results in an inexpensive way to get started with Atmel products. Although this programming method work
15v variable power supply circuit
This 15v variable power supply electronic project is designed using 2N3055 transistors. Output voltage of this variable power supply can be adjusted in the range between 1. 5 and 15 volts. This 2N3055 15v variable power supply can provide a maximum current of 500 mA. Stabilization is better than 2%, if the currents do not exceed 350 mA. Voltage is
Cuckoo Sound Generator Circuit
This circuit generates a two-tone effect very much alike the cuckoo song. It can be used for door-bells or other purposes thanks to a built-in audio amplifier and loudspeaker. Used as a sound effect generator it can be connected to external amplifiers, tape recorders etc. In this case, the built-in audio amplifier and loudspeaker may be omitted...
DC Drill Speed Controller Circuit
With the help of this DC drill speed controller circuit you can control the number of revolutions of your drilling machine. A mini-drill machine is always..
Simple Flashing LED Light Based On 555
This project shows you how to build simple flashing light based on IC 555. The 555 has function as clock generator with dutycyle less than 100 and more than 50. The other components are Voltage regulator, 3 power amber LED and passive component like resistor and capacitor..
Car alarm circuit diagram
FM receivers with PLL
This article describes some simple FM direct conversion radio receivers with phase-locked loop (PLL). This receivers uses the method of locking the local oscillator frequency with the input signal . All this FM receivers are based on the circuit shown in fig. 1. This is a combined oscillator and mixer, and it works as a synchronous detector. Th
Imagine that is morning , you barely anticipate the bus for work and you can`t find your keys. If you suffer from this situation frequently, this circuit is ideal for you. A fizzle is the only thing you have to do. The overall circuit is small enough to attach it to your keys..
150-Hz Oscillator/Counter Circuitt Card Schematic Diagram (Assembly A21)
Thrifty 2Hz Clock
CMOS circuits are known for their low current consumption. This is particularly important for battery-powered circuits. Unfortunately, oscillators often r..
Solent Radio Control Model Boat Club
A "servo slower" which has now evolved into a Servo Controller. `Servo slower` units are used to reduce the slew-rate (traverse time) of proportional servos. The most common use in model boats is to control the rotation of a servo-controlled gun turret, where trying to do so by transmitter stick movement alone results in unrealistically rapid...
A Regenerative Receiver with AGC for 80 and 40 Meters
Here`s a dual-band Regen that came from some encouraging emails from Jerry (K9UT) and another gentleman named Harvey, who built my original AGC-80, and its experimental "Regenerodyne" successor, the AGC-80/30. Jerry and I have corresponded on several occasions, and he tells me that he enjoys both receivers and that they work surprisingly well for
how to make simple earthquake sensor
The article shows a circuit idea which incorporates an innovative way of detecting the minutest of shocks caused by a possible earthquake tremor. The circuit is so sensitive that it is able to detect tremor of 4 on the Richter scale, yet remains unaffected to loud sounds or irrelevant bangs or noises. I have seen a number of different circuits
USB-FX2 Interface Board (USB-2.0)
pwm using 555 timer ic
The 555 IC is wiredin monostable mode of operation. Please read the article Monostable Multivibrator using 555 Timer for more details. In this mode the output is LOW (0V) when there is no triggering, when it istriggeredvia 2nd pin the output goes HIGH (Vcc) for some time. This time period is determinedby the expression T=1. 11 RC (R=R2 ; C=C2 in...
computer control rc car
24W amplifier using TDA1516
Here is the circuit diagram of a simple 24W mono amplifier using IC TDA1516. The TDA1516 is an integrated class B power amplifier in a 13 pin SIL package. The IC has many useful features such as short circuit protection, load dump protection, thermal protection, reverse polarity protection etc. Here the IC is wired in BTL mode to deliver 24W of pow
UV/IR/Visible LED Flashlight with Intensity Control
Build a 10W LED flashlight that features swappable UV/IR/visible heads. We decided to document the build since this flashlight would fit nicely in a photographer`s kit for light painting, IR illumination, UV reflected photography, or UV fluorescence photography. Our flashlight is based on LedEngin`sLZ4-40_ series 10W LEDs. These are available in...
Simple lie detector circuit design electronic project
This lie detector circuit described eally give two readings: one for the difficult questions and one show subject general emotional state. As electrodes can be used two flexible wires, uninsulated wrapped around the fingers or wrist. Each change of resistance, and therefore the voltage at the input circuit will be amplified by operational amplifie
PLL Stereo FM Transmitter
The circuit shown here is of a good Stereo FM transmitter that can transmit high quality signals up to a range of 70 feet. The circuit is based on BH1417 PLL stereo transmitter IC from Rhom semiconductors. The IC has separate audio processing sections for the left and right channels, pre emphasis circuit for improving signal to noise ratio, crysta
Laser Disc Player Modification
Many of us who invested in Prologic decoders are now looking at Dolby Digital. New formats like DSS, DVD-Video and High Definition Television incorporate this new technology; but what about the old laserdisc format After all, more than 600 laserdiscs feature Dolby Digital/AC-3 audio. For those people who do not currently have the AC-3 RF output...
SERVO CONTROLLER DIGITAL
BPS Servo Controller -Digital is total metering and control solution for servo stabilizers for wide range of input voltage and wide range of load requirement. This reducesproduction overheads like wiring and testing and increases productionrate of the voltage stabilizers. Designed with latest micro-controller technology the servo controller integra
PT2399 Echo Application Circuit
USB li-ion charger revision
An year ago, I`ve shared a circuit of USB li-ion charger based on LM358opamp. The circuit had some problems as reported by commentators that inclide wrong direction of LEDs. Don`t post your email or phone number in the comment box. Only put email address in the email field. Comments are moderated so it may take time for them to appear on the site.
Autonomous Parallel Parking RC Car
We created an RC Car that can identify a parking space and parallel park by itself. The RC Car drives down a street searching for a parking space to its right using a distance sensor. When the car has identified a space, the car checks to see whether that space is large enough to park in. If it determines that there is sufficient space, the car wi
BC548 Heat Sensor Diagram Circuit
Heat sensor circuit can be used to control any device using heat sensor. In this circuit a thermistor and a resistance is connected in series. This arrangement makes a potential divider circuit. Here the thermistor is Negative Temperature Coefficient type. So when the room temperature is increased its resistance decreases simultaneously and more c
powering circuit using serial port
Power a rs232-TTL converter circuit using the serial port so i dont have to have an external power supply to do the job. I read somewhere that the DTS, RTS and TD pins are able to do this. As I am already using the TD pin to send out data, is there any other way that i can use the DTS or RTS pin to power my circuit Besides that, I am using VB to...
Tons of LED Projects to spark your creativity. Light Emitting Diodes are simple to use and make your DIY electronic projects look great..
Simple optical switch circuit
The 555 is proved to be the most versatile and ubiquitous IC all over the world.This is a possible use: simple inverting schmitt trigger..
Protection Circuit for Power Amplifier Output and Loudspeaker
interfacing lcd with arm7 friendly
Stereo decoder circuit using MC1310P
Simple FM stereo decoder circuit using MC1310P IC. 12V operation, 40dB channel seperation. Suitable for stereo FM receivers..
500-kHz Filter Circuit Simplified Schematic Diagram
Microcontroller Interface To The Adc12038 Families
Hartley Oscillator Tutorial and Oscillator Design
Hartley Oscillator Tutorial and the theory behind the design of the Hartley Oscillator which uses a LC Oscillator tank circuit to generate sine waves..
versatile dc dc converter
Stepper Motor Controller
Stepper motors are available in several versions and sizes with a variety of operating voltages. The advantage of this general-purpose controller is that..
LNK616PG 5 volt constant charger circuit design electronic project
A very simple 5 volt constant voltage, constant current (CV/CC) universal-input power supply for cell phone or similar charger applications can be designed using the LNK616PG product from the LinkSwitch-II family. As you can see in the circuit diagram, this low cost charger, adapter accepts a wide range of input voltage, from 85 VAC up to 265 VA
dozen small cmos alarm circuits
This is a selection of small self-contained alarm circuits. They have a very low standby current; and are suitable for battery operation. Some are triggered by normally-open and normally-closed switches. Some react to changes in light or temperature. The result is a variety of output times and patterns..
FM Tracking Transmitter Circuit or Remote Control Transmitter Circuit
The circuit of a FM Tracking Transmitter Circuit or Remote Control Transmitter Circuit is explained using 555 IC and and 2N4392 transistors..
Long distance infrared transmitter circuit diagram
Long distance infrared transmitter circuit diagram. Here is a simple circuit that will give you a pretty long range. It uses three infrared transmitting LEDs (IR1 through IR3) in series to increase the radiated power. Further, to increase the directivity and so also the power density, you may assemble the IR LEDs inside the reflector of a torch. H
lf205 Building a Linux-controlled walking robot
portable mic pre amp 2 transistor
Portable Mic Pre-amp 2 transistor using BC549C, BC547B The electret condenser microphone or microphone`s dynamic range contains a very sensitive..
How To Build A Simple Keypad Switch With A Tamper Alarm
This circuit is designed to be used with the Universal Keypad Operated Switch. A few genuine mistakes - made during code entry - will not activate the device. But repeated attempts to find the correct code by trial and error - will cause the keypad to lock-up - and the Buzzer to sound. Connect the coil of a suitable relay to the Buzzer output - a
LM317 Voltage Regulator
The LM317T is an extremely common positive voltage regulator - many laboratory supplies and other equipment are based on it. It can produce any amount between 1. 25V and up to 35V by adjusting the resistance (opposition to current) between its adjustment pin and ground. Secondly, and this is IMPORTANT, the LM317T is a linear regulator. This means t
Gas Meter circuit
Meteoplug is a client-server. The client application needs minimal storage and computing power, which allows for embedding into "computers" of minimal size and with minimal power demands down to1 watt(depending on efficiency of power supply itcan be 1-2 watts more on mains). These clients upload weather data to a server on the internet which...
tate ambient power module
Hey another cool thing I found is that if you earth both the earth of the circuit to ground and the other end of the antenna to a separate ground, you increase the power dramaticaly, compared to using a normal antenna and coil. I made a similar coil to the one mentioned on the ambient power web page but it didn`t help. I have tested and found that