Showing posts with label light. Show all posts
Showing posts with label light. Show all posts
Sunday, October 26, 2014
Running Disco Light with IC 4017
The following article explains how to design a minimal Running Disco Light Circuit Diagram using IC 4017. The IC 4017 is a 16 pin dual featuring in line package IC consists of a 10 stage decade counter/barrier. further in a row in this area the IC 4017 configuration visit at this point.
![]( "Running")
Read More..
Unpretentious Running Disco Light mechanism by 230V and has ceiling 800 W for every channel load. The circuit can direct in Disco mode furthermore, by concerning narrator terminal to audio transformer known, & switching S1 to audio mode. prevail on other in a row on how to design the plain Running Disco Light Circuit
Wednesday, October 1, 2014
Simple Photo transistor Light Sensor Driver Circuit Diagram
- The computer can be programmed to monitor the output of the light t detector, and automatically arranges for the relevant lights to come when it gets dark.
- The sensitivity can be made adjustable for particular requirements by replacing R1 with a series connected 10 KQ preset and a 2709 resistor.
- This circuit provides a computer with information about the presence of daylight.
- The circuit is simple enough to enable ready construction on a piece of veroboard. Its output is TTL compatible, and logic low when the phototransistor detects light.
- Possible applications include automatically measuring the duration of the daylight period in an autonomous weather station, or in control systems for outside lighting around the home.
Saturday, September 6, 2014
Simple Remote Solar LED light
Introduction
I created this schema in an attempt to make the simplest possible solar powered project. It would make for an excellent science fair project, and would also serve as a good introduction to solar powered schemary. It may also have some practical uses, such as shedding some light into a dark part of your house. The idea is simple, the solar panel converts sunlight into a trickle of electricity. The electricity is used to run a white LED.
Specifications
Operating Voltage: 3.7V DC
Solar Current: 25ma max.
LED Lamp Operating Current: 10-25ma.
Theory
The remote solar powered LED light takes advantage of the current limited nature of solar photovoltaic cells. If light shines on the solar array, current will flow through the schema. For a typical size of solar cell, there is a maximum current that can be produced. The maximum solar cell current is simply matched to a value of current that the LED can handle. If there is enough light to raise the solar panels voltage above around 3.7V, the white LED will light up. The LED regulates the maximum voltage across the schema to around 3.7V.
If the solar panel that you use produces more than 20ma, it may be necessary to insert a series resistor between the LED and the solar panel to prevent the LED from burning out. A 50 ohm 1/4 watt resistor is probably about right for the job, the exact value may need to be optimized according to the solar panel that you use.
This concept could easily be expanded to systems with larger arrays of solar cells and more LEDs. The capacitor is not required, but it will keep the LED from flickering if the panel is briefly blocked, such as when a bird flies by. With 7 solar cells, the LED will only light in fairly bright light, if you use up to 10 solar cells, the schema will work nicely in overcast skies.
For an interesting modification to this schema, replace the 1000uF capacitor with a 1 Farad/5.5V "Memory Backup Capacitor". An Elna DB-545D105 device was tested on the schema, after charging up in the sun for a few minutes, the capacitor was able to light the LED for several minutes.
Construction
Most of the work goes into making the solar panel. Lay out the cells in any pattern. Cut the two pieces of plexiglass and one piece of perforated schema board so that they are wider than the solar array. Stack the three board layers together and drill holes for the mounting screws. When the project is finished, the center schema board will be spaced away from the front and back plastic panels with extra nuts acting as spacers on the mounting screws. The idea is to get an air gap above and below the schema board so that there is room for the solar cells and wiring.
Mount the solar cells on the perf board and solder them into a series string. An easy way to do this is to connect short segments of bare wire-wrap wire to each cell, route the wires through the perf board and solder the ends on the bottom. Connect two wires to the ends of the series string of cells and secure the wires to the schema board. For outdoor applications, seal the edge of the panel with silicone caulk or other water proof material. Also, seal the mounting screws where they pass through the plexiglass.
Connect the LED and capacitor in parallel, wire them across the two power leads. Be sure to get the polarity correct, otherwise the LED wont light up. Solder the parts together. Be sure to heat-sink the LED leads while soldering, LEDs can be easily destroyed with too much heat.
Use
Place the solar panel in the sun, the LED will light. The photo at the top of this page shows the schema operating indoors on a cloudy day. If you put the LED on a long wire, it can be placed in a dark location, such as a corner of a basement. As long as there is a fair amount of light in the sky, the LED will light up. To get the best orientation for the panel, aim it directly at the sun at noon during March or September in a location that is free from shade.
Parts
7-10x photovoltaic cells, rated at 15-25ma each.
1x white LED, high efficiency types work best.
1x 1000uF 15V (or greater) electrolytic capacitor.
1 piece of perforated or printed schema board.
2 pieces of clear plexiglass.
28 gauge bare wire-wrap wire.
24 gauge speaker wire.
miscellaneous screws, nuts, and washers.
silicone caulk.
Tuesday, September 2, 2014
Dome light dimmer for Cars
This unique schema makes your dome light look cool. Usually when the car door is closed, the dome light just goes OFF. With this schema, you can have our dome light fade slowly in brightness and finally go OFF. This slow dimming of the light gives a very good feeling at night. It looks very romantic!
The schema can be explained as follows: When the car door is open, the push to off switch of the door is ON and hence it charges the 22uF capacitor fully. The opamp is acting as a voltage follower and its output is same as the voltage across the capacitor, which is 12V when the capacitor is fully charged. Due to a high voltage at the output of the IC, the transistor saturates, turning ON the bulb to full brightness.
Now when the door is closed, the door switch is pushed in and hence the switch goes OFF. When the switch is OFF, the capacitor starts discharging slowly through VR1 and the 10K resistor and the voltage across it decreases slowly. Hence at the output of IC 741 also the voltage decreases gradually, hence decreasing the base current to the transistor. This produces a slowly decreasing current through the bulb and the bulb fades out and finally when the capacitor is fully discharged, the bulb goes OFF.
After building the schema, with the push-to-off switch in ON position (not pushed in) i.e. the car door open, adjust the preset VR2 to the required initial brightness of the bulb. Then push the switch in to turn it OFF(or close the door) and adjust VR1 for the time to bring the bulb from full brightness to OFF.
I would suggest you set VR1 and VR2 to their maximum values.
Fan on off Control by Light Wiring diagram Schematic
This schema lets you turn on/off a fan by just directing torchlight or other light toward its light-dependent resistor (LDR). The schema is powered from a 5V power supply.
Preset VR1 and a light-dependent resistor (LDR) work as the potential divider. Normally, the LDR’s resistance is high (20 kilo-ohms) in darkness and low (2 kilo-ohms) in light. This value of high and low resistances varies for other LDRs. Preset VR1 is used for setting the intensity of light, while preset VR2 is used for setting the output time period of IC1.
Preset VR1 and a light-dependent resistor (LDR) work as the potential divider. Normally, the LDR’s resistance is high (20 kilo-ohms) in darkness and low (2 kilo-ohms) in light. This value of high and low resistances varies for other LDRs. Preset VR1 is used for setting the intensity of light, while preset VR2 is used for setting the output time period of IC1.
Fan on/off Control by Light Circuit Diagram
When light falls on the LDR, the monostable (IC1) triggers at pin 2, making its output at pin 3 from low to high. This low-to-high transition forms a clock for D flip-flop. The D flip-flop is operated in toggle mode by connecting its Q output to D point. The flip-flop output goes to an inverter (N1). The inverter output is fed to the relay driver transistor.
When the inverter output is low, diode D1 conducts and the current is diverted into the inverter. Hence the relay does not energise. When the inverter output is high, diode D2 conducts and the current is diverted into transistor T. Hence the relay energises.
One terminal of the fan is connected to the normally-open (N/O) contact of the relay, while another terminal is connected to the neutral (N) of mains. The mains live (L) is connected to the pole of the relay. When the relay energises, the fan turns on. Otherwise, the fan remains off.
Switches S1 and S3 are for initial resetting of the monostable (IC1) and D flip-flop (IC2), respectively, and switch S2 is used for setting the D flip-flop. Paste a piece of paper on the face of the LDR so that it doesn’t get activated by ambient light. Use a torch to light the LDR.
After initial resetting of the monostable and D flip-flop, the inverter output goes high and the fan turns on via the relay. When light falls on the LDR, the fan goes off. If torchlight is again directed toward the LDR, the fan turns on. The sequence repeats.
Initially if switch S2 is used to set the D flip-flop, the fan is held ‘off’. The relay does not energise as the Q output of D flip-flop goes high to make the inverter output low. Directing the light towards the LDR at this moment turns the fan ‘on.’
Sourced By: EFY Author: V. Gopalakrishnan
Wednesday, August 27, 2014
WIPRO 916VWA19 LCD MONITOR SMPS Power Supply and BACK LIGHT INVERTER SCHEMATIC
SMPS & Back-light inverter schema diagram & Troubleshooting
No Power
Tuesday, August 26, 2014
Emergency Light using Phone Line Wiring diagram Schematic
This is a schema for emergency lighting with LEDs that uses electricity from the telephone line. Generally the phone line has a DC voltage 48V and somewhere around 20 mA, and when the phone rings, the voltage rises to 96V AC. This works in a way that the phone line will not be busy while the LEDs are turned on and when you pick up the phone, the light goes off and lets you use your phone normally.
Emergency Light using Phone Line Circuit Diagram
Subscribe to:
Posts (Atom)
