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Build a BTL Stereo Amplifier Circuit Diagram with TDA7052 , you can see circuit and start make a BTL Stereo Amplifier Circuit Diagram with TDA7052. BTL Stereo Amplifier Circuit Diagram with TDA7052 

This simple Telephone Record Control Circuit Diagram will allow you to connect any tape recorder that has a mic and remote input to a phone line and automatically record both sides of a conversation when ever the phone is in use. You will need to take a couple of voltage readings before connecting the circuit. First determine the polarity of your phone line and connect it to the circuit as shown and then determine the polarity of the remote input and connect it to the circuit. Circuit operation is as follows. When the phone is on hook the voltage across the phone line is about 48volts dc. When the phone is off hook the voltage will drop to below 10volts dc. When the line voltage is at 48volts the FET is off which causes Q2 and Q3 to be off. When the phone is picked up the FET turns on along with Q2 and Q3 which turns your recorder on. The tape recorder must be in the record mode at all times. As you can see the power source for the circuit is the phone line.  Telephone Record Con...

Theremin circuit shown in this schematic diagram uses digital component, so we can call it a digital Theremin. This circuit employs  logic inverter 74C04 or CD4069 hex inverter and CD4046 phase-locked-loop (PLL) IC.  The CD4069 logic inverter is operated as a fixed-frequency oscillator with  frequency around 100kHz. The CD4046 is operated as a variable frequency oscillator which is adjustable around 100kHz. The exact center frequency of the on-chip oscillator is determined by R4, C2 and R3. Here is the schematic diagram of the circuit.  Digital Theremin Circuit Diagram The frequency of variable oscillator frequency circuit can be shifted several kilohertz by moving your hand approaching the antenna since the C2 and the antenna form an equivalent parallel capacitance. The frequency of the variable oscillator should be set to the same frequency of fixed oscillator when there is no hand or human body close to the antenna.  This  calibration is done by adjustin...

This is a Variable 5 to 20V DC Supply Circuit Diagram . If you are looking for a low drop voltage regulator that can provide a power supply of 1A with an output voltage of between 5V and 20V DC, National Semiconductor LM2941 Low Dropout Adjustable Regulator is that you can pick to make use of. It's a typical dropout voltage of 0.5V which means that the input supply need only must be 0.5V DC over the desired output voltage.  Variable 5 to 20V DC Supply Circuit Diagram   Its other features include internal short circuit current limit and reverse battery protection. As shown in the schematic below, the regulator has five pins which consists of the ON/OFF control, Input Voltage, Output Voltage, Ground & Adjustable pins. ON/OFF is used for the purpose of switching on & off of the regulator. The capacitors C1 & E1 are to be placed as close as feasible to the regulator.  The output of the circuit can be varied by varying the worth of potentiometer VR1 from 5V DC to 2...

How to Build a High-Performance Interruption Detector Circuit Diagram . The circuit presented here detects interruption in security systems. Its features include no false triggering by external factors (such as sun-light and rain), easy relative positioning of the sensors and alignment of the circuit, high sensitivity, and reliability. The circuit comprises three sections, namely, transmitter, receiver, and power supply. The transmitter generates modulated IR signals and the receiver detects the change in IR intensity. Power supply provides regulated +5V to the transmitter and the receiver.  The power supply and the speaker are kept inside the premises while the transmitter and the receiver are placed oppo site to each other at the entrance where the detection is needed. Three connections (Vcc, GND, and SPKR) are needed from the power supply/speaker to the receiver section, while only two connections (Vcc and GND) are required to the transmitter. The transmitter is basically an ast...

Half of RL1 and RL2 manipulate the switching and the other is connected to an application. Relays are 200 ohms above ground and at one point are referenced to positive that turns them off. Description: RL1 (which is off) applies plus voltage from its armature and latches RL2 “on”. The application terminals are set to [A]. The condition changes when S1 is activated, voltage is applied to RL2 latching RL1 “on” releasing S1 turns RL2 “off”. RL2’s armature is then directed to R1. Terminals are set to [B]. When S1 is pressed again, the relays negative side are referenced to positive, RL1 turns “off” (there’s no current flow). RL2 turns “on” when S1 is released, terminals are set to [A]. There is slight lag between relays depending on how long S1 is held. Relay Toggle Switch Circuit Diagram Note:  If different relays are used, adjustment of R1’s value may be required. For example, OEG relays (12vdc, 270 ohm coil) need R1 at 60 - 70 ohms. The prime motivation for this design was to avoid ...

Build a 1.2-36V 5A Adjustable Power Supply circuit diagram with LM317 . This circuit is a simple power supply circuit. 1.2 - 36V adjustable bench power supply with 5A of output current. Max input voltage is 37V and output is adjustable via potentiometer between 1.2 up to 36 volts. TIP147 PNP darlington transistor boosts the current of LM317 from 100mA to 5A. LM317 is the most useful and inexpensive adjustable regulator and for this circuit you can also use LM317 L that can give 100mA, that's enough for transistor bias.   1.2-36V 5A Adjustable Power Supply Circuit Diagram  D1 and D2 are protection diodes because when you turn the circuit off the output capacitors are discharging and can damage the transistor or regulator. 100nf capacitors are in parallel with electrolytic capacitors to remove high frequency noise because large value electrolytic have large ESR and ESL and can't remove high frequency noise.

This is the 25W Class-A power audio amplifier circuit. The output devices are MJL4281A (NPN) and MJL4302A (PNP), and have high bandwidth, fantastic SOA (safe operating area), high linearity and high gain. Driver transistors are MJE15034 (NPN) and MJE15035 (PNP). All devices are rated at 350V, using the power transistors having a 230W dissipation and the drivers are 50W. 25W Class-A Power Audio Amplifier Circuit Diagram  The supply voltage must be a maximum of ±25V. This supply is simply obtained from a 20-0-20V transformer, recommended current is 1A.  All resistors ought to be 1/4W or 1/2W 1% metal film for lowest noise, with the exception of R9, R10 and R15 which ought to be 1/2W varieties, and R13, R14 have to be 5W wirewound.  Using the suggested and advised 25V supplies, Q4 will typically not need a heatsink. The output drivers (Q5 and Q6) recommended to use a heatsink, even though it doesn’t have to be big.

The circuit was designed to build a Regulated Power Supply with Stability at 3A will provide a regulated voltage from 40 V to 70 V in a 3 A current. 2N3055 – a complementary Silicon Epitaxial-Base planar NPN transistor mounted in Jedec TO-3 metal case for use as power transistor. BD243 – an epitaxial-base Silicon NPN transistor intended for wide variety of high speed switching and power amplifier applications such as series and shunt regulators, and driver and output stages of high-fidelity amplifiers. BC303 – a PNP silicon planar epitaxial transistor used for AF drivers & outputs, for AF medium power amplifiers, and for switching applications up to 1 A. There are times when some applications are requiring a regulated power supply that has relatively high output voltage and stability. All of these features are being attained in the design of this circuit. The voltage output of the circuit can range from 40 V up to 60 V while carrying a current of 3 A while providing stabilization...

The post explains a simple 21 watt LED lamp circuit module which can be used as a direct replacement for a standard halogen lamp in motorcycles. The proposed "halogen" LED lamp replacement module image can be seen below: Conventional filament type halogen lamp is shown below: The image at the top shows an example LED lamp replacement for a standard halogen bulb fitting shown below it. With the easy and extensive availability of LEds, today it's quite possible to make any desired LED lamp module at home for replacing other forms of less efficient lamp options. So here we'll discuss how to make the proposed halogen LED lamp replacement circuit. Let's learn the procedures: Referring to the above image, we can see the LEDs are wired over 7 separate PCBs and then wired together to form one single module. Each board can be seen with 3 LEDs each, constituting a total of 21 LEDs. 3nos LEDs are selected because the supply 12V available from the vehicle allows only 3nos t...

A very easy build Electronic Project of dual polarity power supply circuit, requires few parts, and is adjustable from 0-15 volts. It is great for powering op amp circuits, as well as other circuits that require a dual supply voltage. Dual Polarity Power Supply Circuit Diagram: Parts List: C1, C2 2200uF 35V Electrolytic Capacitor C3, C4, C5, C7 1uF 35V Electrolytic Capacitor C6, C8 100uF 35V Electrolytic Capacitor R1, R4 5K Pot R2, R3 240 Ohm 1/4 W Resistor BR1 2A 30V Bridge Rectifier U1 LM317 Adjustable Positive Regulator U2 LM337 Adjustable Negative Regulator T1 30V Center Tapped 2 Amp Transformer S1 SPST 2 Amp Switch MISC Heatsinks For U1 And U2, Line Cord, Case, Knobs For Pots, Wire Notes: Since this project operates from 120 (or 220, or 240, etc.) volts AC, it MUST be built inside a case. U1 and U2 get quite hot and will require heatsinks. A fan is usually not needed. You can, of course, add a volt and amp meter. U1 and U2 can only go down to a minimum of +-1.2V. If you need to g...

This is a simple Fog Lamp Switch Circuit Diagram. This circuit recommended to have a rear fog light on a trailer with the additional requirement that, when the trailer is coupled to the car, the rear fog light of the towing car has to be off. The circuit shown here is eminently suitable for this application. The circuit is placed near the rear fog light of the car. The 12-V connection to the lamp has to be interrupted and is instead connected to relay contacts 30 and 87A (K1, K3). When the rear fog light is turned on it will continue to operate normally.  Fog Lamp Switch Circuit Diagram If a trailer with fog light is now connected to the trailer connector (7- or 13-way, K2), a current will flow through L1. L1 is a coil with about 8 turns, wound around reed contact S1. S1 will close because of the current through L1, which in turn energizes relay Re1 and the rear fog light of the car is switched off. The fog light of the trailer is on, obviously. The size of L1 depends on reed conta...

Build a Simple Digital Electronic Lock Circuit Diagram . This is a Build a Simple Digital Electronic Lock Circuit Diagram . The digital lock shown below uses 4 common logic ICs to allow controlling a relay by entering a 4 digit number on a keypad. The first 4 outputs from the CD4017 decade counter (pins 3,2,4,7) are gated together with 4 digits from a keypad so that as the keys are depressed in the correct order, the counter will advance. Simple Digital Electronic Lock Circuit Diagram As each correct key is pressed, a low level appears at the output of the dual NAND gate producing a high level at the output of the 8 input NAND at pin 13. The momentary high level from pin 13 activates a one shot circuit which applies an approximate 80 millisecond positive going pulse to the clock line (pin 14) of the decade counter which advances it one count on the rising edge. A second monostable, one shot circuit is used to generate an approximate 40 millisecond positive going pulse which is applied...

This is a simple High voltage inverter circuit diagram . This inverter circuit works with a transistor and transformer and other components to increase the voltage becomes high. Input supply voltage ranging from 3V to 6V DC, later it was raised to high voltage AC. However, in this inverter circuit output current is very small, probably under 0.1A even smaller. However, its use you can apply it on a fluorescent lamp 10W maximum power only, and that too takes time to switch on fluorescent lamps.  High voltage inverter circuit diagram Part List R1 = 4K7 R2 = 2K2 R3 = 330K C1 = 100nF C2 = 100nF 275V C3 = 0.22uF 275V Q1 = D506 L1 = 100 times winding, with 0.8mm diameter copper wire L2 = 50 times winding, with 0.8mm diameter copper wire L3 = 5000 times winding, with 0.4mm diameter copper wire

There are monitors which only have three BNC inputs and which use composite synchronization (‘sync on green’). This circuit has been designed with these types of monitor in mind. As can be seen, the circuit has been kept very simple, but it still gives a reasonable performance. The principle of operation is very straightforward. The RGB signals from the VGA connector are fed to three BNC connectors via AC-coupling capacitors. These have been added to stop any direct current from entering the VGA card. A pull-up resistor on the green output provides a DC offset, while a transistor (a BS170 MOSFET) can switch this output to ground. It is possible to get synchronisation problems when the display is extremely bright, with a maximum green component. In this case the value of R2 should be reduced a little, but this has the side effect that the brightness noticeably decreases and the load on the graphics card increases. To keep the colour balance the same, the resistors for the other two colo...

This is a Simple Power Pulse Using by LM350 and NE555 Circuit Diagram . This circuit can use to drive lamp,power LED,DC motor etc. Adjust R5 for output amplitude.Adjust R1 for output power . Power Pulse Circuit Diagram The LM350 is adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 3A over a 1.2V to 33V output range.This circuit requires 5-15V power supply.