Popular Circuits Page 84
- Page 84
-
This article briefly describes the NTSC-PAL TV Signal Identifier (LM1881). Although this circuit is very easy to understand, but also very practical. Circuit elements in depth understanding of the grasp of the principle is very effective. Do you know the....
-
-
2N3904 is the NPN transistor. Looking at the flat face, the left lead is Emitter (pin 1 in schematic), the middle lead is Base (pin 2 in schematic), the right lead is Collector (pin 3 in schematic). Another end of 50 Ohm resistor to +5v pin on Arduino. (An....
-
This circuit provides a cheap alternative to the LM3915 series LED displays. The meter relies on a square-wave oscillat..
-
This is very simple charger 9V - 30V battery charger with main operation by IC LM317L and 2N222 transistor. Direct input DC voltage, the recomended capacitor is 1000uf. It can be filtering Output voltage and make long-lasting battery. And easy to make this....
-
This circuit is even simpler and employs a 6V feed from one of the stator connections on the vehicle`s alternator. This is connected to a 6V automotive relay (RLY1) which controls a Continuous Duty Solenoid (RLY2). This solenoid electrically connects or....
-
331 circuit shown in FIG. It uses two-way thyristor controlled motor start and stop. It has no contact, no noise sound, no spark, etc., suitable for frequent operation of the o..
-
-
4QD manufacture motor speed controllers so all our H bridges are PWM. Here`s a simple switch circuit for reversing and stopping a motor without any control of speed. Two inputs, A and B, control the bridge. With both high (or open circuit) both ends of the....
-
-
When an inverter is biased with one resistor from its input to output in the range of 100 KOhmhm to 10 and is capacitor c..
-
This circuit sends MIDI program changes. It's useful as a guitar pedalboard remote...
-
Two comparators and a summing amplifier that generate differential harmonic spectra comprise a simple frequency multiplier. The resulting circuit can extract harmonics from a sine, triangle, sawtooth, or any other sloping-sided waveform. With a....
-
-
The FM oscillator/modulator is a voltage-control led oscillator, which exhibits a nearly linear output frequency versus input voltage characteristic for a wide deviation. It provides a good FM source with a few inexpensive external parts..
-
This is the very simple circuit diagram of 150W power amplifier. The circuit is easy enough to built without PCB. The power output range is about 100-150W depends to the power supply and the Darlington`s you use for the amplifier. Heatsink is a must since....
-
Hbrightness metal halide lamps typically have an efficacy of greater than 100 lumens/watt and have a lifetime of 20,000 hours. HID lamps produce light using a technique similar to that used in fluorescent lamps where mercury atoms are excited by an....
-
-
-
When the light falls on the LDR, it becomes low ohmic. The voltage at the junction of LDR/R2 charges the C2 via the R1 slowly. After about 10 seconds, the capacitor voltage reaches the input threshold of U1. Then U1 generates a square wave signal with a....
-
-
The mic inputs are amplified about 100 times or 40dB, the total gain of the mixer including the summing amplifier is 46dB. The mic input is designed for microphones with outputs of about 2mV RMS at 1 meter. Most dynamic microphones meet this standard. The....
-
Simplified Analog Input Schematic
This schematic represents the input circuitry for a single input.
This circuit is a track and hold. The idea is that the input waveform may reach a peak at any instant as the drummer strikes the pad. When that....
-
The problem is when i connect the 8051 to the encoder the data send is not received at the receiver but as soon as the 8051 connections are removed the transmisison works perfectly. thus manually the RF communication works perfectly i. e the 8 bit data which....
-
An electrically operated rolling shutter usually has a standard control panel with a three-position switch: up, down and stop. If you would like to automa....
-
Most products use multiple LEDs to provide adequate backlight for a display. Because the LED`s brightness depends on its forward current, these multiple diodes commonly connect in series to ensure that the same current flows through each of them. You need....
-
One very important Part of a Tube Amplifier is the Power Supply. It is crucial for the quality of the whole system. Especially beginners encounter problems like Hum or Drift that can become quite annoying. But resue is ahead: The following circuit uses a....
-
Battery-powered light control delay lighting a small lamp, a sudden power outage or night to ask a blown fuse, the room was dark, it is difficult to find a match and candles: S..
-
In the present era, the various technologies we can see. On average, every three months there is a new technology. So not supprisingly, with so many unique and innovative equipment trigerred. Car`s radio without antenna are our project. This is an idea....
-
The inspiration for the VCO
in Figure 1 came from Texas Instruments
application notes of years ago, detailing
the use of unbuffered U-type inverters
for use in ring oscillators. The
application notes circuit consists of only
the inverters. The circuit....
-
This one is using a 16F876 PIC, MCP1047A temperature sensor ( X2 ), MCP1541 voltage reference and MCP6022A opamp. The display is a 2 row HD74780 based 2X16 char, SII L1652BIJ2 but any other display based on HD74780 can be used. Meantime the thermometer is....
-
At a T connection, it`s clear, but at a cross it`s otherwise not clear, especially if there are no junction dots elsewhere as in your schematic. It looks like the bottom of Is and the right side of R2 are supposed to be connected to ground, but your....
-
Rl and R2 hold the inverting input at half supply voltage. R4 applies feedback to increase the input impedance at pin 3. Pin 3, the nonin-verting input, is connected to the junction of R3 and C. After the switch is opened, C charges via R3. When the....
-
Cable and xDSL modems are experiencing increasing popularity. For this reason, many designs are now required to interface with existing telephones at the subscriber`s location. The subscriber line interface circuit (SLIC) within the modem has the additional....
-
Building your own Zapper. 1 Compositor 1 micro farad, C2, I like the un-polarized because it allows you not to worry about positive an negative sides. If you do get one with a longer leg that`s the positive, see schematic for proper placement. 1 resistor for....
-
This is a small battery operated Tracking transmitter which broadcasts a repeating radio signal which can be detected by a directional antenna. The transmitter broadcasts an isotropic (radiates in all directions) signal on the FM band. An ordinary FM radio....
-
This is a very basic circuit for fading video signal shown in Eletor Electronics magazine. You can use this between two video equipments. The circuit is so simple that the impedance matching and some other things are not exactly correct, so might not always....
-
The voltage that control a V/F converters will be displayed if we use a frequency counter, which is directly proportional to the input voltage. A 1 second time...
-
Here is a project of a simple touch switch circuit. This circuit and can also be used to activate a relay in the place of LED and resistor. The circuit is quite sensitive because we have used the two transistors as a Darlington pair. The gain is first....
-
Default setting for the UART is 9600 baud, 1 start bit, 1 stop bit, no parity. You can configure this paramter by placing the file "CONFIG. TXT" to the USB thumb drive. Currently only the baudrate can be configured. Example: Once the device is connected and....
-
A circuit that uses both positive and negative alternations in an alternating current to produce direct current. There are two types of Full-Wave Rectifier circuits; one that only uses two diodes but requires a center tapped transformer [shown below], and....
-
The goal of this project was to make an interactive baseball game inspired by pinball. There is a solenoid-powered bat and a pitching mechanism that utilizes a motor and lever arm setup. Both of these are controlled by buttons so that two people can play....
-
This is a programmable clock timer circuit that uses individual LEDs to indicate hours and minutes. 12 LEDs can be arranged in a circle to represent the 12 hours of a clock face and an additional 12 LEDs can be arranged in an outer circle to indicate 5....
-
To do this, first, we must make the appropriate physical connections from the arduino board to the LCD. Then after, we must write the code so that whatever text we want displayed comes up on the LCD. LCDs are pretty much the standard now in order to display....
-
These circuits could be used as the basis for Model Railroad DCC Boosters or PWM motor controllers. The first schematic is for a basic 3 Amp - DCC Booster using the LMD 18200 CMOS, H-Bridge.
Included in the design is a 5Volt regulator that supplies....
-
-
This lead acid battery charger circuit is designed in response to a request from Mr. Devdas. C. His requirement was a circuit to charge two 12V/7AH lead acid batteries in series. Anyway he did not mentioned the no of cells per each 12V battery. The no of....
-
A number of readers have asked how to tell when the Lead-Acid Battery Zapper has done its job and battery desulphation is complete. In the author`s experience, batteries that are going to respond to this treatment will generally show quite a high peak....
-
The TDA3567 is a monolithic integrated decoder for the NTSC colour Television standards. It combines all functions required for the demodulation of NTSC signals. Further more it contains a luminance Amplifier an RGB-matrix and Amplifier These Amplifiers....
-
This wireless headphones transmitter assures a affection accession over 2 meters. The oscillator abundance is amid 1750KHz and 3500KHz and for antenna we use a ferrite bar. IC1 amplifies the audio arresting and TC1 is a buffer. D1 signals that the....
-
The circuit was constructed around the functionality of a Class A amplifier to create a headphone circuit. BC308 an epitaxial planar PNP transistor used....
-
-
This ultrasonic anemometer serves for the 2-dimensional capture of the horizontal components of the wind speed and the wind direction as well as the virtual temperature. On account of the high measuring rate this device is suited very well to capture gusts....
-
This circuit will be particularly useful to those hobbyists who use a breadboard` to try out ideas and who also use a simple home-made` DC power supply consisting of a transformer, rectifier, smoothing capacitor and protective fuse, that is, one without over....
-
-
-
This is a simple, cheap device that can be connected to any serial port to control most components that have infrared remote controls. I designed and built it (on a solderless breadboard) in 1991. In 1992 I wrote a lengthy description of it for an....
-
Shortly after the 2002 WCRG, Ori Barbut started tinkering with Ben Hitchcock`s FRED SE. His aim was to create a simple, solar-powered, light-seeking head design (and in particular, to create a head design that could be based on a FRED photopopper kit with....
-
I bought a Doepfer LMK3+ keyboard from a very pleasant chap in Dunedin, via TradeMe, a popular New Zealand auction site. The keyboard features a nice, piano-like Fatar keybed in a rugged flight case. Here`s a photo of another LMK3+, taken from a recent....
-
This circuit has been designed to provide a clearly visible light, formed by 13 high efficiency flashing LEDs arranged in a pseudo-rotating order. Due to low voltage, low drain battery operation and small size, the device is suitable for mounting on bicycles....
-
The USB(Universal Serial Bus) specification provides the ability and energy. This change highlights series and parallel connections of the past, allowing an increase in the number of devices that can use a Personal computer. This simple circuit USB charger....
-
Another adjustment of application opamps to adapt a ability accumulation is apparent below. The ability agent requires an added ambagious to accumulation the op-amps with a bipolar voltage (+/- 8 volts), and the abrogating voltage is additionally acclimated....
-
Many excellent ISP (In System Programming) designs exist for 8 bit AVR microcontrollers. However, most require a pre-programmed microcontroller, or the "Chicken or Egg" problem: you can`t program microcontrollers unless you have one already programmed.....
-
With only four transistors and four resistors, the diamond buffer does not require much. Some harsh critics would add that it does not deliver much either. I have covered the circuit and its modification here before, for example in Blog 232 and Blog 187. But....
-
The control of both direction and of proportional motor speed is achieved by rotation of a single potentiometer. The motor driver is an SGS integrated circuit L293 which will drive up to 1 amp in either direction, depending on the logic state of input 1 and....
-
This Digital Circuit describes a Digital Blood Pressure Meter concept which uses an integrated pressure sensor, analog signal-conditioning circuitry, microcontroller hardware/software and a liquid crystal display. The sensing system reads the cuff pressure....
-
Automotive electronic locks circuit principle is shown in Fig. ICl dedicated lock IC 5G058, it O ~ feet respectively external key switch to the positive power supply, which is ..
-
Our reader Andrea (andrea[dot]perugia[-at-]gmail[dot] com) sent his circuit to us, and he creates the circuit for educational intent. The main purpose is to show that you can toggle an output state electronically, although physically you use only a push....
-
Capacitive dimmer switch circuit shown in Figure 9. It is the use of capacitive reactance principle of alternating pairs made...
-
The output voltage is = 0.707 x Vin, at the center posititon. The output voltage is = Vin, at either extreme position...
-
The circuit given here is of a very useful and accurate digital voltmeter with LED display using the ICL7107 from Intersil. The ICL7107 is a high performance, low power, 3. 5 digit analog to digital converter. The IC includes internal circuitry for seven....
-
An Astable Circuit has no stable state - hence the name "astable". The output continually switches state between high and low without without any intervention from the user, called a `square` wave. This type of circuit could be used to give a mechanism....
-
Using this 555 timer DC motor control electronic project you can control speed of a 6 volts DC motor, by simply rotate left or right the 50 k potentiometer. ..
-
Simple, easily transported VSWR meter consists of high-gain amplifier, narrow-bandwidth (100-Hz) selective amplifier tuned to 1000 Hz, and variable-gain output amplifier driving low-cost VU meter. Ideal for nulling type VSWR measurements. Draws only about....
-
How often does it happen that you close down Windows and then forget to turn off the computer? This circuit does that automatically. After Windows is shut....
-
The recommended Prescaler is ridiculously simple. It consists of just one IC, a TV tuner prescaler, the Philips SAB6456A, which can divide by 64 or by 256. This chip is widely available both new and in the surplus market at much lower prices than....
-
When the handset is lifted and power is applied to the circuit, Q2 is fed base current through R2, which in turn drives Ql. C2 is charged via R3 in series with D1 to (Vz1 -0. 7) V. When the minimum operating Vnv voltage is reached, power on reset occurs....
-
This circuit will energize and de-energize a relay at the push of a button. Any type of momentary action push-to-make switch can be used. Pushing the button once - will energize the relay. And pushing it a second time - will de-energize the relay I`ve drawn....
-
It is one of the most versatile general purpose instruments capable of measuring dc and ac voltages as well as current and resistances. The solid-state electronic multimeter (or VOM) generally consists of the following elements. In addition, the instrument....
-
This is an alarm circuit which will go off when any motion or movement is detected. Once it detects this motion, the circuit will trigger an alarm buzzer to sound which will remain on until the power is disconnected from the circuit. This alarm circuit`s....
-
-
The problem of setting any one of four modes of a µC-operated process has a straightforward solution: Have the µC check the states of some 4 bits of a µC register or an input port and then execute one of the four predetermined subroutines according to the....
-
-
If you look carefully at the schematic you will notice the input is feed into the voltage divider. This is because the Schmitt Triggers all turn on a....
-
The search loop may be constructed in several different ways; however, the method offered here should get you headed in the right direction. Refer to Fig. 2 as a guide for constructing the loop. The loop form should be constructed from non-metallic and....
-
The GT4124 is a broadcast quality monolithic integrated circuit
specifically designed to linearly mix two video signals under
the control of a third channel.
Referring to the Functional Block Diagram, the input signals
are applied to conventional....
-
Electrical lines which include lighting circuits begin from the main distribution panel of the installation and each line contains three conductors: phase, neutral and ground. All three conductors reach to the terminal point of each luminaire and if it has a....
-
-
A high impedance DC voltmeter using a uA741 IC is shown here. The operational amplifier is used as a non-inverting DC amplifier in which the negative feedback is through a DC meter requiring 1mA for full scale deflection. Since R6 is 100 Ohms, the meter will....
-
A very simple proximity detector can be made using this electronic scheme. This electronic circuit reacts to the presence of a conductive object within a particular field. Circuit sensitivity can be adjusted with potentiometer P1 for the desired distance.....
-
IC2 is wired as a low frequency astable with a cycle period of about 6 seconds. The slowly varying ramp waveform at C1 is fed to PNP emitter follower Q1, and is then used to frequency modulate alarm generator IC1 via R6. IC1 has a natural center frequency of....
-
As more than one switches are to be controlled, we have to transmit a number of bits through IR transmission to indicate which is key is pressed on the remote and accordingly which switch of the switch-board to control. In this project, this is done by using....
-
This is a complete Arduino Uno-compatible standalone system, and will be fully assembled, tested, and programmed before shipping. You may choose one of several TC4 applications to be pre-programmed into the board. If you would like to use the TC4 system, but....
-
This project is a simple 12V to 220V modified sine-wave inverter using 555 timer IC and CD4017 decade counter. This inverter can deliver 300W continuous power and around 500W max power output (short period). A very good inverter for uninterruptible power....
-
-
An integral part of modern multimedia computer is the presence of two active audio speakers (mounted on a monitor or set next to it). Due to a number of physical limitations of the two small computer speakers can not achieve a good reproduction of the full....
-
Software delay routine in 8051 for generating different time delays. Sine wave generator circuit using software delay in 8051. AT89C51 is the microcontroller used in this project....
-
This circuit is a laser alarm system like the one we see in various movies. It uses a laser pointer beam to secure your valuables and property. Essentially, when the beam gets interrupted by a person, animal or object, the resistance of a photodiode will....
-
The VCA project illustrates the use of the VCA_Setup and VCA_Data components in ADS. These components are part of the ADS behavioral model suite found under the System - Data Models palette. "Amp_wBothMatches_setup. dsn" is a schematic for extraction of....
-
-
The following shows over a 1993 VW Passat electrical schematic. Features: Vehicle content, electrical wiring schematic. Component: Console switches, electric Windows, ABS control unit and ABS hydraulic unit, engine control module, automatic control unit,....
-
hello , I am planningto build Digital Thermometer using ATmegsa8 and LM335. Can Somebody tell me how should i go about ?? I want to display it on....
-
The 12F629/675 PICs are small 8 pin DIP devices that are ideal for our applications. They include and internal oscillator, a comparator, an analog/digital converter and timers. The Microchip PICkit1 is an ideal USB programmer. PicBasic Pro (PBP) is an easy....