Switching Circuits
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When the phototransistor is stroken by IR light it conducts and the voltage between the 1Mohm resistor(arbitrary) and the phototrans drops from VCC to lower values. When the voltage drops lower than VCC/3 the 555 is triggered and goes high (from 0 TO VCC)..... -
Any "button" of any remote control may be used to work this universal switch. The button must be pressed for two seconds (determined by R3 and C2) before the relay will operate. Once operated the circuit will remain in this state (latched) until reset. To.... -
This sensitive sound operated switch can be used with a dynamic microphone insert as above, or be used with an electret (ECM) microphone. If an ECM is used then R1 (shown dotted) will need to be included. A suitable value would be between 2. 2k and 10kohms..... -
The hardest part for this circuit was the title. It is quite easy to miss the sound of a doorbell if you are watching TV, this circuit gets round the problem by providing a visual indication, i. e. a lamp. As an alternative, a LED could also be used. You.... -
This simple circuit can be wired into your headlight switch to provide automatic switching between high and low beam headlights when there is oncoming traffic. Simple electronics project with circuit diagram.... -
This circuit is built around a 555 timer using very few components. Since the circuit is very simple, even a novice can easily build it and use it as a controlling device. A laser pointer, now easily available in the market, can be used to operate this.... -
This article describes how to build an opto-isolated power switch for controlling heavy loads with logic levels.... -
Normal operation of the light switch gives gentle illumination (LA1). For more light, simply turn the switch off and then immediately (within 1 s) on again. The circuit returns to the gentle light set-ting when switched off for more than 3 s. There is no.... -
To create the circuit you will need to connect a switch as an input and an LED as an output to the Arduino. This means that you will need a switch, an LED, a 10k © resistor, a 470 © resistor, a blue or yellow jumper wire, and a red jumper wire. The Arduino.... -
This simple circuit is a line-level audio signal muting switch based on a soft-action power on/off process. When the S1 switch is closed, R4, C1 and Q4 JF.... -
Today we are going to explain about a simple circuit which is used to switch on/off any electrical device remotely through a relay using the normal TV/VCR.... -
This 555 timer clap switch circuit electronic project is designed using some common electronic parts. This 555 timer clap switch circuit electronic projec.... -
With this sound activated switch, control by sound may be very useful, not just on a robot but also for a bit of home automation, for example a sound-acti.... -
This circuit can switch two or more devices on and off in response to a series of rapid handclaps. The claps are picked up by an electret microphone and a.... -
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.... -
Mechanical contacts have the disadvantage that they wear out. That is why it is practical to use an electronic ‘touch switch in some situations. With suc.... -
In these times with viruses and other threats from the Internet it would be nice to have reassurance that the PC cannot be infected. That is why this circ.... -
Turn ON or OFF electrical devices using remote control is not a new idea and you can find so many different devices doing that very well. For realization.... -
This circuit is built around a 555 timer using very few components. Since the circuit is very simple, even a novice can easily build it and use it as a co.... -
The circuit senses mains current supplied to a master` device and switches slave` equipment on or off. This feature is useful in a typical hi-fi or home computer environment where several peripheral devices can all be switched on or off together. A.... -
This circuit allows an SPST momentary pushbutton to act as a push-on push-off switch, using a DPDT latching (bi-stable) relay. It was originally intended to allow a single pushbutton switch on the dash of a vintage car to provide a latched function. The.... -
At the heart of this circuit is a precision integrated temperature sensor type LM35 (IC1), which provides an accurately linear and directly proportional o.... -
It is sometimes necessary for an RC (remote control) model to contain some kind of switching functionality. Some things that come to mind are lights on a.... -
A relay circuit to function as a DPDT toggle which is controlled by a momentary switch. I strive to keep my circuits simple with little or no integration (555`s, transistors, etc). The circuit is shown active or on mode. Half of RL1 and RL2 manipulate the.... -
Remote Control Mains Switch As the only electronics engineer in my family and circle of friends, it is sometimes not possible to evade an appeal for help .. -
This simple circuit shown int the schematic diagram actives the switch using sound. We can use this circuit for various applications, such as automatic (s.... -
This circuit is especially designed for those who often need to wake up early in the morning. Ordinary alarms in electronic watches are not loud enough an.... -
This circuit switches a printer s USB connection from a PC to a laptop. What was needed was a method of allowing a laptop to use the printer occasionally.... -
Nowadays a lot of intercom units are equipped with video cameras so that you can see as well as hear who is at the door. Unfortunately, the camera lens is.... -
In this circuit the 555 timer is used in a novel way, as a voltage controlled switch.The old and omnipresent NE555 can be very good at someth.... -
Hi again, I have a simple audio switching circuit that is giving me a problem. I am using a CD40106 Schmitt Trigger in conjunction with a CD4066 CMOS switch to route.... -
This key code switch circuit is a type of electronic circuit that is created to replace conventional normal key switch. Without inserts a keys. But you can....
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
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.... -
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.... -
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.... -
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.... -
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,.... -
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.... -
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.... -
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.....
Popular Circuits
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