Light switches controlled by external signal ( 46 ) :

• Light level controlled switches

• 741 Based Light Sensor   
• Dark Activated Switch   
• Dark/Light Activated Relay   
• Electronic Night Light   
• IR Remote Toggle Switch - Use ANY infra red remote to toggle this switch on or off. Relay output.   
• Light Activated Relay   
• Light controlled switch - output a control signal suitable for relay depending on the light level   
• Light Operated Switch - Originally published in Everyday Practical Electronics, December 1995   
• Light Switch - switch that will be activated by light falling on a sensor   
• Photo Electric Street Light - circuit to switch off and on a street lamp at dawn and dusk   
   

• Audio controller switches

• Audio Auto Shutoff - purpose of this circuit is to automatically turn off any device plugged into its power outlets after a certain period of time of silence   
• Hand Clap Electronic Control - turn relay on and off by hand clap   
• Signal Detecting Auto Power-On Unit - switches on relay when detects sound input   
• Sound Operated Switch   
• Voice activated switch - this switch is activated by voice level above the noise and not activated by background noise   
   

• IR remote controlled switches

• Infa-Red Remote Control - simple circuit which controls one relay output   
• Infrared Remote Control - allow you to turn on any piece of equipment that operates on 115 volts ac   
• IR Toggle Switch - a simple circuit which can switch a relay off/on by pressing any key on any IR remote controller   
• Remote Control Lighting - IR transmitter, receiver, switch and dimmer   
   

• Radio controlled switches

• Ensemble domestique HF 4 voies - 4 channel radio remote controller which controls 4 relays, text in French, try   
• Four-way remote control uses series transmission - four channel remote controller system which uses 433 MHz band   
• R/C Switch - This circuit is a so-called "Radio Controlled Electronic Switch". It can be used to switch on/off anything electrical, whatever it is. Here are a couple of examples: navigation lights, landing gear, sound systems, glowplug driver, bomb release, parachute, search lights, gyros, and so on. This circuits connects to a RC car controller servo output.   
   

• Other remote controlling

• Short dc power-line pulses afford remote control - If you face the challenge of adding a second, independently controlled light source to an existing ceiling lamp controlled by a wall switch, you may find that stringing a second power line is impossible. This design uses remotely controlled control circuit located at the lamps' site.   
   

• Person movement detection

• Passive-Optical Person Detector - Ordinary proximity detectors use infrared sensors which respond to the warmth of the human body. But there?s a simpler way: we can use ambient lighting and detect changes in illumination. Any move a person makes causes a change in the ambient lighting. This circuit uses an ordinary phototransistor as its "eyes" to detect these changes.   
• Pyroelectric Infrared (PIR) Motion Sensor - This document includes circuit design as well as an excellent tutorial on PIR devices.   
   

• Load sensing switches

• Load Sensing Automatic Switch - apply power to the entire audio system by turning on one item, simple circuit   
• Mains Power Switcher - allows you to turn all the equipment on or off, by operating the switch on just one item, unit works by sensing if current is being drawn from the master socket, if so it powers up the other (slave) sockets   
• Low Cost Fan Control with Hysteresis - This application can be used to control many different devices. In this example, a compressor current is sensed, and when it reaches a selected set point, the circuit turns on a relay, which controls a fan motor. The circuit is generated with a minimum number of parts, and includes hysteresis.   
   

• Other circuits

• Alternating ON-OFF Control   
• A Touch Control Switch for Fluorescent Lamps   
• Capacitive Sensor: Special design for shop-windows animation Useful for many types of touch controls - The purpose of this circuit is to animate shop-windows by means of a capacitive sensor placed behind a post-card-like banner. The card is placed against the glass inside the shop-window, and the visitor can activate the relay placing his hand on the card, from the outside. Especially suited for toy-shops, the circuit can activate model trains, small electric racing cars, lights etc.   
• Cellular Phone Helper - activates a variety of devices when your cellular phone is in use, pdf file   
• Courtesy Lamp - 15 seconds delayed switch-off for 220V AC lamp, a good idea for bedroom lamps   
• Electronic touch switch - This touch switch is a so-called hum-induced type, the advantage of this type is that you need only a single contact.   
• Multiple remote points control on/off switch   
• Semiconductor relay circuits - basic switching elements for various controlling applications   
• Smart Phone light - The circuit shown here is used to switch on a lamp when the telephone rings, if the ambient light is insufficient.   
• Soft ON/OFF switch - Modern electronic equipment incorporate "push-to-on-push-to-off" switches that do not make the clicking noise as with old equipment. An example of this is the power button on a ATX computer cabinet. Here is a circuit that does the same. It can be used to turn on/off any electronic/electrical equipment that operates on any range of voltages.   
• Stop/start circuit using a relay and pushbutton switches - for use when you want to manually restart a device after a power failure   
• Switch debouncer isolates input and output   
• Switching Circuits - collection of switching circuits for temperature, light level and button controlled switching   
• Temperature Monitor - a heat activated sensor   
• Three Way Touch Lamp - A three-way switch to control a lamp (off-dim-bright, etc.) uses an NE555 timer to generate a one-second pulse, triggered by ambient ac fields that are picked up by the human body. Read also the   
• Touch Switch - electronic device that enables us to control a circuit by simply touching a sensor   
• Zero Crossing AC Switch Oscillator - This circuit will switch on and off a resistive or inductive load up to 800VA with the possibility to adjust both the on and off period. Switching takes place during the zero crossing of the sine wave. The on period is adjustable between 0.3 to 4sec while the off period is adjustable between 0.2 and 10sec.   

 back to : Links >> Electronic Circuits >> Light controlling electronics