Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
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
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
Timer and Interrupt
There are 4 timers in PIC18 which are timer0 to timer3. Timers are used when precise timing event need to be generated. Timers are usually used in conjunction with interrupt to keep the timing accurate. This guide will show an example of using timer0 to count a timer for every second. The circuit used for this example is the same as the circuit...
Timer switch circuit
A 100 second delayed turn ON relay RL1 switch, if plug power +12V in circuit. In Fig.2 see a two range 6-60 second and 1-10 minute auto turn off relay timer circuit, with 555.
Timer Circuit with optocoupler
A small circuit that can find a lot applications of measurement time. She has the possibility us inform with sound signal from the BZ1. At the same time, exist the possibility drive a external circuit via the optocoupler IC2, after we connect the applicable circuit in contacts [ A ] and [ B ]. The circuit is based on IC1 (4060), which include in...
A wide rage auto turn OFF timer covering 1 minute to 20 hours in three ranges with S1. As soon as power is applied to the circuit the IC1  starts to oscillate happily and feeds clock pulses to the IC2 . The IC2  and IC3  give a combined count rate of 81920 before the output of the IC3  goes high and turns Q1 on. With...
Digital Clock with Solar Regulator
The basic clock circuit (top schematic below) is similar to the binary clock (on another page) and uses 7 ICs to produce the 20 digital bits for 12 hour time, plus AM and PM. A standard watch crystal oscillator (32,768) is used as the time base and is divided down to 1/2 half second by the 4020 binary counter. One half of a 4013 data latch is...
18 LED sequencer timer
The question sometimes comes up of how to cascade 4017 decade counters for more than 10 sequencial stages. The LED sequencer below shows a possible solution using a few extra parts. When power is applied, the 15K resistor and 10uF cap at pin 15 will reset the counters to the zero count where pin 3 is at +12 and all other outputs are at zero. The...
Dc to Dc converter using 555 Timer IC
When the power supply input to IC1 is the output pin 3 at a frequency of 1 kHz. The frequency is Q1 and Q2, which will continue to use push pool work interchangeably. If this is the positive output signal Q1 Q2 will run the delete function this reason, C2 and C3 capacitors are half-wave alternating. This US police siren schematic circuit is...
Lm556 Datasheet Pinout Application Circuits Dual Timer
PIC16F628 Digital Clock Timer circuit and explanation
This clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit time and control an external load. It can be programmed to time from 1 to 59 minutes. The clock includes a calendar with leap year and optional daylight savings adjustments. The timer output can be set from 1 to 59 minutes and manually switched on and off. The clock also
555 timer Electronic roulette wheel circuit and explanation
This electronic circuit is a simple version of an electronic roulette game and is based on the 4017 IC which is a 10 stage decade counter/divider. It is driven by another versatile IC 555 configured as a voltage controlled oscillator (VCO). The 555 timer is connected as an astable multivibrator. When the S1 switch is pressed, the capacitor C3 get
555 timer bassed Electronic lock circuit with explanation
A very simple electronic key code lock circuit that require few external components can be constructed using this schematic diagram. This electronic key code lock circuit is based on a common 555 timer circuit and some other common components. This low cost key code circuit use six switches that needs to be pressed to open the lock, but only two
The following schematic diagram is four hour timer circuit. Feature : easy to build, 3 hours 53 minutes total time, 9V supply voltage. Component : 555 timer IC, Resistor, capacitor, switch, transformer, LED, CD4040B, Relay, BC547 transistor, 1N418 diode, variable resistor. [wiredworld. tripod. com]
Production of automatic re-set timer for crime prevention buzzer that uses PIC
The crime prevention bell device that I produced about 20 years ago works still in the active service. It worked many times to make the thief not operate well and not go into it. The bell keeps ringing generally though the bell rings as for the crime prevention buzzer when the thief was about to enter. With this, after the fixed time, it is stoppe
Relay Timer with ATmega8
Timers are widely used in industrial and domestic application for automating tasks. Microcontrollers can be used to design versatile and accurate timers with.
Random timer circuit using a Attiny24A
This random timer circuit is based on a Atmel ATTINY24 avr driving one power relay. You can use this circuit to switch on and off other circuits randomly. For example, when using this circuit on a model railroad you can turn on and off parts of the animated or moving scenery to create a more dynamic view. This circuit was designed to be used on a
555 timer compo entry 2
This entry is a 4 step sequencer controlling an `Atari Punk` synth with a greyscale NTSC video visualization of the output audio, built using two 558 quad-timers and two 556 dual-timers. Sorry in advance for the poor video quality, I will try to get a direct capture next week when I get back from GDC, but I was in a rush to make the contest deadli
555 Timer Contest Entry
This is a motor speed control circuit that allows safe and easy control of 115VAC "universal motors" like drill motors, blender motors, other power tools, etc. The motor is controlled directly by a triac-diac component that is found in variable-speed universal motor devices (such as electric drills. ) The component will not allow current to flow th
555 Timer as Monostable Multivibrator
A monostable multivibrator (MMV) often called a one-shot multivibrator, is a pulse generator circuit in which the duration of the pulse is determined by the R-C network, connected externally to the 555 timer. In such a vibrator, one state of output is stable while the other is quasi-stable (unstable). For auto-triggering of output from quasi-stable
Adjustable Analog Timer Circuit
This Adjustable Analog Timer circuit starts timing when switched on. A green LED lights to show that timing is in progress. When the time period is over the green LED turns off, a red LED turns on and a bleeper sounds. The time period is set by a variable resistor and it can be adjusted from 1 to 10 minutes (approximately). It could be used to set
Metal Detector using 555 Timer Suite
A actual simple metal detector cyberbanking activity can be advised application a simple 555 timer chip ambit. As you can see in the schematic ambit, this cyberbanking activity requires few alien cyberbanking genitalia.
The time interval of this circuit can be varied digitally through the DIP switches. The time code however must be set in BCD form. A 120 Hz signal generated by doubling the line frequency is used as the time reference. This is then divided to 1 pulse per minute by the ICs 1 and 2. The counter IC3 counts backwards- that means it starts to count fro
LED Flasher Circuit Using 555 Timer IC Schematic Diagram
This is a simple LED flasher project that uses a common 555 timer IC for its operation. It is configured as an astable mode which means that its output is a square wave oscillator. Two LEDs are connected to its output in such a way that when one LED is ON, the other LED will turn OFF. It uses only 10 simple parts that are easily available at any e
Timer Garage Door Circuit Schematic Diagram
Timer Garage Door Circuit schematic diagram, printed circuit board
555 Timer with a Speaker
555 Timers are very fun to encounter and experiment with. They can be used as a timer and can be set to a certain frequency. In Part II of Electronic Project I, we created a circuit that would get an LED to flash. This time we are going to add a speaker so that we can hear the frequency that is being emitted. · I did not put an estimate next to t
555 Timer To Control Motors
I am a mechanical engineering student, and for a part of my design project I wish to use a timer as so the motor switches off about 40-50 seconds after activation. The 555 timer chip is a rectangle with a indented o on the top, i assumed this was equivalent to the cutout semi circle (please tell me i don`t have the chip the wrong way around). With
Extend Timer Range For The 555
Anyone who has designed circuits using the 555 timer chip will, at some time have wished that it could be programmed for longer timing periods. Timing periods greater than a few minutes are difficult to achieve because component leakage currents in large timing capacitors become significant. There is however no reason to opt for a purely digital s
Simple Astable 555 Timer IC Flasher
For a lower parts count than the 2 transistor multivibrators, 2 LEDs can be alternately flashed with a 555 integrated circuit configured as shown in Schematic 2. I chose the combination of a 2K2 and a 47K resistor to determine the oscillation frequency along with the 10 uF capacitor connected to pins 2 and 6. You can practically change the (R Spee
Bathroom Water Heater Timer
Electronic switch ES1 connects the frequency determining capacitor to the input of clock oscillator N1. The logic level that exists at the Dm terminal of IC; is shifted towards output Q at a speed that is defined by P1, which enables defining fixing times between roughly 1 and l0 minutes, 9 minutes being a commonly used value. When the star ·r but
Capacitors and the 555 Timer
ECEN 2250 myDAQ Experiment Capacitors and the 555 Timer.
Timer Thermostat Circuit
This circuit turns-off an amplifier or any other device when a low level audio signal fed to its input is absent for 15 minutes at least. Pushing P1 the device is switched-on feeding any appliance connected to SK1. Input audio signal is boosted and squared by IC2A & IC2B and monitored by LED D4. When D4 illuminates, albeit for a very short peak, I
White LED Voltage Booster Uses 555 Timer IC
This voltage-booster circuit for driving one or more white LEDs uses a 555 timer as its main element ( see the figure ). The timer, IC1, functions as a resettable astable multivibrator where R1, R2, and C2 are the timing components. When the supply voltage, VS, is first applied, D1 conducts and reservoir capacitor C1 charges to a voltage just less
Frequency Meter Circuits
VU Meter Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity