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
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
I need to make a small 4-10 second (changeable) delay circuit that pulses a cell phone vibrational motor every 0.75 seconds. I`m using a 9 volt battery. Could anyone..
The Echorec delay is a superb piece of engineering! In their quest for perfection Binson got many important aspects of the design right, maintaining a balance between simplicity and adding genuinely useful features to this classic echo machine. The engineers developed their own unique magnetic drum storage medium that offered superior reliability
10 minute time delay by fet 2n3819
This circuit is a basic function of the FET 2N3819, which acts as a switch. In the conduction and not conduction. It runs contrary to the transistor. The..
5 Minutes Time Delay using CD4093
This be delay timer circuit model to be simple. It be the character delays to close electric all appliances. By fix the time about 5 minute. It can fine..
On After Delay with Mosfet
That be On After Delay Circuit. I uses mosfet in the circuit for delay easy more than the transistor. By have the work of the circuit be when press , S1 ,..
Switch off delay circuit by 2N4871
This circuit prevents surges. From the opening is switched off or power failure. The damage to electrical appliances. The circuit will switch to use a short..
designing audio circuit tape delay
Hi, this is my first post here. For the past few days I`ve been building a tape delay unit. Mechanically, it works well, but I still need to design a circuit to link all the parts together. This is, however, beyond my current level of ability, and I was wondering If I could get help. The tape heads are cassette tape heads, and have a resistance of
high and low voltage cut out with delay and music circuit diagram
Voltage variations and power cuts adversely affect various equip- ment such as TVs, VCRs, music systems and refrigerators. This simple circuit will protect the costly equipment from high as well as low voltages and the voltage surges (when power resumes). It also gives a melodious tune when mains power resumes. When mains voltage is normal, the DC
555 Timer Time Delay Circuit
555 Timer Time Delay Circuit LEDs indicate at a glance what the status of the circuit is at any given moment. Once the reset switch, SW2, makes..
150 - 210 secs analog delay timer project for control of devices that need to have a minimum off timer before power can resume to prevent damage to the devices
time delay relay circuit
A diesel tractor that has a magnetic reed switch in the fuel tank to indicate low fuel. This switch is open when there is fuel in the tank, and closes when the level drops below it. When this switch closes a 12v relay is energized to disengage the fuel control and shuts off the engine. The problem is, sloshing fuel causes the float switch to...
LED strobe has independent delay and duration
This circuitis not complex, but it saved the day in an application involving visual inspection of the spray pattern of fuel injectors for quality and consistency. In this application, xenon strobe lights did not work because they take up too much space, and the light they emit is too intense.
12V Time Delay Relay Circuit
Protect your equipments with this tiny 12V time delay relay circuit. The SMPS based power supply of these modern electronic devices is vulnerable to spikes..
Time Delay Switch with Triac
This time delay switch circuit is useful to switch on an AC load such as lamps after the delay of three minutes. This protects the load from inrush current and transients at power on which may be detrimental to the device. The time delay switch is directly connected to the AC lines to derive power to the components. Resistor R1 drops AC voltage an
Time Delay Relay Circuit with 555
This time delay relay circuit is built with IC NE/SE555, produced by Intersil which contains a precision timer. Stability to temperature variations is 0.00..
Circuit diagram for generating time delay with 555 IC
This circuit based project demonstrates the working of 555 timer in astable mode to generate pulses of time period 0. 5 second. This pulse can be further used for anything where we need a pulse such as to blink a LED or to create fashionable blinking lights. Image below shows internal circuitry of NE 555 timer which can be used in astable and monos
Audio amplifier output relay delay
This is a simple circuit which I built to one of my audio amplifier projects to control the speaker output relay. The purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circuit is wait around 5 seconds ofter the power up until the spakers are switched to the amplfier outp
Time Delay Relay II
A muting delay & DC offset protection circuit
A low pass filter is merely a stable state-space system that has an input and spits out an output. If the input is a quasi-periodic signal, then the output would simply be the same quasi-periodic signal with a phase shift. Only difference would be that this system would have to transition from some initial condition (which would be ground, or...
High And Low Voltage Cut Off With Time Delay
The power line fluctuations and cut-offs cause damages to electrical appliances connected to the line. It is more serious in the case of domestic appliances like fridge and air conditioners. If a fridge is operated on low voltage, excessive current flows through the motor, which heats up, and get damaged. The under/over voltage protection circuit
DC Protection Time Delay for Loudspeaker circuit
The particular circuit combines enough operations, as Smooth departure of benefit of AC line of network, with delay 1sec, to the transformers of power supply of amplifier, via the RL1 and the resistance Rx. (see block diagram). [ 2 ] Delay of connection of expenses of final amplifiers, in headphone, in order that noises emanating from the charge...
Low Voltage High Current Time Delay Circuit
In this circuit a LM339 quad voltage comparator is used to generate a time delay and control a high current output at low voltage. Approximatey 5 amps of current can be obtained using a couple fresh alkaline D batteries. Three of the comparators are wired in parallel to drive a medium power PNP transistor (2N2905 or similar) which in turn drives...
Generating a Delayed Pulse Using The 555 Timer circuit
The circuit below illustrates generating a single positive pulse which is delayed relative to the trigger input time. The circuit is similar to the one above but employs two stages so that both the pulse width and delay can be controlled. When the button is depressed, the output of the first stage will move up and remain near the supply voltage un
Power-On Time Delay Relay circuit
Here`s a power-on time delay relay circuit that takes advantage of the emitter/base breakdown voltage of an ordinary bi-polar transistor. The reverse connected emitter/base junction of a 2N3904 transistor is used as an 8 volt zener diode which creates a higher turn-on voltage for the Darlington connected transistor pair..
Power-Off Time Delay Relay circuit
The two circuits illustrate opening a relay contact a short time after the ignition or ligh switch is turned off. The capacitor is charged and the relay is closed when the voltage at the diode anode rises to +12 volts..
Long Delay Timer Circuit
This timer was designed mainly to switch off a portable radio after some time: in this way, one can fall asleep on the sand or on a hammock, resting assured that the receiver will switch off automatically after some time, saving battery costs. R1 and C1 provide a very long time constant. When P2 is momentarily closed, C1 discharges and the near ze
Boss DD-2 Digital Delay Guitar Pedal Schematic Diagram
The DD-2 is one of the best digital delay pedals and actually sounds very analog! The pedal was sold from 1983 and it did officially go out of sale 1986 but it was relaunched without changes as the DD-3 (later versions of the DD-3 use a different design). The circuit is built around the RDD63H101 IC and a 12 bit A/D converter producing a flat freq
Boss DM-2 Delay Guitar Pedal Schematic Diagram
There are at least 3 different versions of this circuit. The first DM-2 version was using the MN3005 BBD and the MN3101 Clock Driver IC (PCB marking: ET5214-510). Later they changed the clock driver to MN3102 and the BBD to the low current version of the same circuit, the MN3205 (PCB markings: ET5214-510A an
There is one slight drawback to our flashing LED program. Each instruction takes one clock cycle to complete. If we are using a 4MHz crystal, then each instruction will take 1/4MHz, or 1uS to complete. As we are using only 5 instructions, the LED will turn on then off in 5uS. This is far too fast for us to see, and it will appear that the LED is...
Phase Delay Network for 3D Audio Enhancement
3D enhancement is needed to create a fully 3-dimensional sound for most stereo multimedia products. Usually, simple phase-delay circuits is used to produce a widening effect on the perceived sound field. However, there is transaural acoustic crosstalk effect. The following figure shows transaural acoustic crosstalk effect and schematic diagram of
Car Interior Lights Delay
Most cars do not have delayed interior lights. The circuit presented can put this right. It switches the interior lights of a car on and off gradually. This makes it a lot easier, for instance, to find the ignition keyhole when the lights have gone off after the car door has been closed. Since the circuit must be operated by the door switch, a sli
high and low voltage cut off with delay and alarm
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...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial