Infrared / Light Controled Switch

DescriptionThis circuit is simple remote controlled relay. It is able to switch lamps or other devices.D1 can be a phototransistor or LDR or an infrared transistor.Circuit is controlled with an IR remote like a TV remote control (when IR transistor is used)You can change circiut sensitivity with RV2.Part List U1:7805U2:74111U3:lm358Rl1:5v relayRV2:10k potR1:390RR2:10kD2:1n4007(for transistor projection)C1:100uf 16VC2:100uf 16VQ1:TIPP112J1:SIL2 conector for input power(circuit can work with 9V)J2:terminal block M2 PCB source : http://www.electronics-lab.com/projects/motor_light/026/index.h...

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12V To 24V DC-DC Converter Circuit

This simple DC-DC converter can provide up to 24V from a 12V source. It can be used to run radios, small lights, relays, horns and other 24V accessories from a 12V vehicle with a maximum draw of about 800mA. It can be used to charge one 12V battery from another, or step up the voltage just enough to provide necessary overhead for a 12V linear regulator. Using one op-amp as a squarewave oscillator to ring an inductor and another op-amp in a feedback loop, it won't drift around under varying loads, providing a stable 24V source for many applications. With a wide adjustment in output this circuit has many uses. Parts Part Total Qty. Description Substitutions R1, R2, R3, R4, R8, R76100K 1/4W Resistor R51470...

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Power Supply Short Circuit Protection

Power Supply Short Circuit Protection Description This circuit designed to be used with: 0-30 Vdc Stabilized Power Supply With Current Control 0.002-3 A Components values are shown in shematic. Connect 741 +Vcc to D1 anode in main circuit Connect 741 -Vcc to D3 catode in main circuit U1 needs a 5v +Vcc connect pin 4 of U1 to 5v Please note that +Vcc is above absolute maximum ratings of 741 which are +/- 22V, this may cause damage to OPAMP. You may need to add a LM7805 to power OPAMP. U1 needs at least 5v +Vcc. Usage - Power ON power supply then press START button to connect outputs to power supply. - If output is shorted the relay disconnects output from power supply. - Fix the short circuit and then press START again to connect output...

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0-30 VDC STABILIZED POWER SUPPLY WITH CURRENT CONTROL 0.002-3 A

This is a high quality power supply with a continuously variable stabilized output adjustable at any value between 0 and 30VDC. The circuit also incorporates an electronic output current limiter that effectively controls the output current from a few milliamperes (2 mA) to the maximum output of three amperes that the circuit can deliver. This feature makes this power supply indispensable in the experimenters laboratory as it is possible to limit the current to the typical maximum that a circuit under test may require, and power it up then, without any fear that it may be damaged if something goes wrong. There is also a visual indication that the current limiter is in operation so that you can see at a glance that your circuit is exceeding or...

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1.2 - 36V / 5A Adjustable Power Supply

DescriptionThis is a very simple and adjustable voltage power supply. Max input voltage is 37V and output adjustable between 1.2 to (vcc - 3) volts.Q1 is a power PNP Darlington transistor and is used to boost current of  LM317. It's the most useful adjustable regulator and for this circuit you can also use LM317L thats can give 100mA, thats enough for transistor bias.D1 and D2 are protection diodes because when you turn the circuit off the output capacitors discharing and can damage the transistor or regulator.R1 is 2W and other resistors are 0.25WR1 is LM317 current limiting resistor and R2 is Q1 bias resistor all capacitors are 50V RV1 is 5k multi turn volume pot.100nf capacitors are in parallel with electrolytic capacitors to remove...

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PIR Motion Sensor and Schematic Diagram

Introduction The objective of this project is to use inexpensive PIR sensor to detect if a human has moved. To build this project I use a PIC18F25K20 microcontroller to detect if the sensor had change state and it will emit a sound from the speaker or piezo, the MCU also detect the voltage of the battery in the startup, the algorithm it´s very simple it use an interrupt on change to detect the change on the PIR sensor. PIR Sensor PIR sensors allows you to sense motion, almost always used to detect whether a human has moved in or out of the sensors range. They are small, inexpensive, low-power, easy to use and don't wear out. For that reason they are commonly found in appliances and gadgets used in homes or businesses. PIRs are basically...

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How To Build a Laser Security System

Got a mystery to solve? Somebody’s been making off with your stuff, and you don’t have a clue who it is, do you? Here’s your chance to catch them in the act. To make a laser security system you will need:     A laser pointer     Some Duct tape     A few small mirrors     An L.M.741 microchip     A 220-ohm resistor     A photocell     An inexpensive digital camera     An extra small screwdriver     A wire coat hanger     Some thin, insulated wire     A printed circuit board     A 9 volt battery     A 9 volt battery clip     Soldering equipment     A pair of wire cutters    ...

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Water Alarm Circuit

Project Summary this circuits remember us that our tank is near about to get full so that we turn off our motor switch but for this circuit you need a function generator specially Project Description This circuit gives out an alarm when its sensor is wetted by water. A 555 astable multivibrator is used here which gives a tone of about 1kHz upon detecting water. The sensor when wetted by water completes the circuit and makes the 555 oscillate at about 1kHz. The sensor is also shown in the circuit diagram. It has to placed making an angle of about 30 – 45 degrees to the ground. This makes the rain water to flow through it to the ground and prevents the alarm from going on due to the stored water on the sensor. The metal used to make the...

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300 Watt MOSFET Real HI-FI Power Amplifier

Project Summary My passion for excellence progressed over the past 40 years to developing sonically superior amplifiers to the highest possible standards, providing life like sound performance. Project Description  Figure 1 I am committed to sharing my experience of the RAS 300 with other enthusiasts sharing my passion for perfection.I designed this minimalist amplifier to be durable, simple to operate while offering high fidelity equivalent to the original sound source and would recommend partnering this amplifier only with other products of outstanding quality. When I set out to design this amplifier, my aim was to create a product most suitable for the reproduction of complex music and speech signals. Although I placed high emphasis...

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Car Alarm System

Project Summary The project is almost acceptable of a car alarm system, which could be completed with a transmitter and receiver. Project Description This project is practical, and the hex file, it can get. Button switch to disable the system. Button to open the door for when the driver enters the cars, and system deactivates the trigger button, if starter switch is closed, the device is completely passive. In this mode, only open or close doors button can be used. proteus 7.8 or 7.9 Project Files File NameFile Size hex14.43 KB  source : http://www.eeweb.com/project/abba_ba/car-alarm-system ...

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TDA7360 Stereo Amplifier Test and Application Circuit Diagram and Datasheet

Car radio application using class AB Audio Power Amplifier usually has TDA7360 inside it. It is a 22W bridge or stereo audio ampwith features such as minimum external components, high output power, fixed gain, clipping detector and etc. Above circuit diagram shows this TDA7360 stereo test and application circuit schematic. Value recommendation of each external components of this circuit can be described as follows: 1. C1 for input decoupling (CH1) is 0.22 uF2. C2 for input decoupling (CH2)3is 0.22 uF3. C3 for supply voltage rejection filtering capacitor.4. C4 for 22uF standby ON/OFF delay5. C5 minimal 220uF for standby-pass6. 100 nF for C6 with its ability to supply by-pass7. 2200 uF for the C7 of Output decoupling CH2The TDA7360 bridge/stereo...

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RA53 Stereo Headphone Amplifier Connection Schematic

This stereo headphone amplifier device may provide up to ten channels of headphone monitoring if a 1/4” Link Input/Output jack is provided for connecting two RA53 units together. The schematic below illustrates a possible operation for this RA53 stereo headphone amplifier. As you can see, the headphones are connected to the outputs on the front panel side, when the others to the rear panel. Another connection possibility can be: 1. The Left and Right Inputs to the RA53 are connected to the mixer’s sub outputs, but could be connected to auxiliary sends or even main outputs. 2. The RCA Auxiliary Inputs are connected to a playback deck. 3. For individual monitoring, a stereo TRS connector could be plugged into a stereo auxiliary send from the...

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12V Portable and Mobile Power Supply Circuit Diagram

A suitable 12V portable and mobile power supply circuit design is shown in the circuit diagram below. This type of power supply can be built quite inexpensively and needs only a minimum of circuitry. This circuit will give output current of 1 amp, well stabilized and smoothed. The smoothing and regulation is provided by IC1 7812 which is a 12V monolithic voltage regulator. This portable power supply unit incorporates output current limiting and is therefore not damaged by accidental short term short circuits or other forms of output overloading. 12V Portable and Mobile Power Supply Circuit Diagram can be built using components as follow: Resistor 1/3 watt 5% R1 1.8k Capacitors Cl 2200uF 25V electrolytic C2 100nF polyester (C280) C3 100nF...

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27MHz Transmitter-Receiver Radio Control PCBs and Schematic Diagram

This article provides information about 27 MHz Transmitter-Receiver Radio Control related to its PCB assembly/construction. The picture below shows the schematic diagram of the transmitter using IC TX2B(TX-2B/RX2B Datasheet). You will be explained with the instruction for constructing the PCBs (assembly, tuning, transistors, IC, resistors, capacitors (Disk Ceramic, Metallised Polyester, Electrolytic)) for both transmitter (Inductors, LED, Zener Diode, Crystal) and receiver (Zener Diode, Inductors, Resistors, Transistors) with the part value and specifications listed, and how to wiring up the PCBs for both transmitter and receiver.Find complete description on 27MHz Transmitter-Receiver Radio Control PCBs and Schematic Diagram in this pdf datasheet...

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Remote Control for Home Appliances

Connect this circuit to any of your home appliances (lamp, fan, radio, etc) to make the appliance turn on/off from a TV, VCD or DVD remote control. The circuit can be activated from up to 10 metres. The 38kHz infrared (IR) rays generated by the remote control are received by IR receiver module TSOP1738 of the circuit. Pin 1 of TSOP1738 is connected to ground, pin 2 is connected to the power supply through resistor R5 and the output is taken from pin 3. The output signal is amplified by transistor T1 (BC558). The amplified signal is fed to clock pin 14 of decade counter IC CD4017 (IC1). Pin 8 of IC1 is grounded, pin 16 is connected to Vcc and pin 3 is connected to LED1 (red), which glows to indicate that the appliance is ‘off.’ ...

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RF based Wireless Remote Control

This circuit utilises the RF module (Tx/Rx) for making a wireless remote, which could be used to drive an output from a distant place. RF module, as the name suggests, uses radio frequency to send signals. These signals are transmitted at a particular frequency and a baud rate. A receiver can receive these signals only if it is configured for that frequency. A four channel encoder/decoder pair has also been used in this system. The input signals, at the transmitter side, are taken through four switches while the outputs are monitored on a set of four LEDs corresponding to each input switch. The circuit can be used for designing Remote Appliance Control system. The outputs from the receiver can drive corresponding relays connected to any household...

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