IR Light Dimmer v.1 circuit schematic with explanation

IR Light Dimmer v.1
This is a device for adjusting lights in your home with any type of remote controller (tv, dvd, video,…). Today we are using many devices in our homes to improve quality of our life and this is another example on how you can enhance a simple procedure like switching the lights ON/OFF. It may be difficult to many of us to stand up from our chair only to switch lights, so try imagining yourself doing this with your remote controller.



http://www.electronics-lab.com/projects/motor_light/044/index.html

Projects/IR light dimmer v1

Projects/IR light dimmer v1
This is a very simple IR light dimmer that you will wish to have sooner or later, especially those who are lazy enough to get up and turn off the lights. There are two versions of PCB for two sizes of capacitors, so PCBs are: 32.5 x 26.5mm and 28.5 x 27mm.

Features of current beta version of firmware:
- Soft start (gradually turning on the light bulb)
- Soft down (gradually turning off the light bulb)
- Learning IR codes from RC5 and NEC remotes
- Dimming in 10 levels by using only IR remote
- Previous dimm-level remembering when operating with remote
- Sleep timer in duration of 1.6min for 60Hz version and 2min for 50Hz version
- ON/OFF control with wall pushbutton

http://www.elektronika.ba/617/ir-light-dimmer-v1

IC 741 based Bar graph light meter

If you want simple meter the intensity of the light in a simple way. This circuit is very interesting, because with a LED display with 5 levels.The main equipment is uA741 the most popular op-amp circuit, to used the photo transistor is a device for receiver a lighting to change is electricity very low. We use IC1 acts boost up current, or to compare the voltage levels.The VR1 adjusts the offset voltage to the LED display complete , the intensity of light to measure.The power supply size use +9 V and -9V.

Using IC 741 for Audible light sensor

This is audible light sensor circuit that is based the IC741 op-amp IC. This circuit light sensor one,these are use two LDRs for detector lower lightly.
The 741 is pulse oscillator generator output to small speaker. The VR1 have value 50k acts as to fine sensitivity of light sensor. The speaker use small size only because output has low current.

S:eleccircuit.com

Night Light based on photocell

Description.

Many automatic night light circuits had been published here. This one uses a photocell for detecting the light intensity. At full light the resistance of the photocell will be few ten ohms and at darkness it will rise to several hundred ohms. The IC1 uA741 is wired as a comparator here. At darkness the resistance of photocell increases and so the voltage at the inverting input of the IC1 will be less than the reference voltage at the non inverting input. The output of the IC1 goes to positive saturation and it switches ON the transistor to activate the relay. By this way the lamp connected through the relay contact glows. The diode D1 works as a freewheeling diode.

• The circuit can be assembled on a Vero board.
• Use 9V DC for powering the circuit.
• POT R7 can be used to adjust the sensitivity of the circuit.
• The relay K1 can be a 9V, 200 Ohm SPDT type.
• L1 can be a 230V,60W lamp.
• R8 can be a ORP 12 photocell.

CMOS IC 4060 based night security light

Here is a simple circuit switches on a light around 2 hours after midnight, the time at which most of the robberies taking place.

This simple circuit is build around a CMOS IC 4060 to obtain the required timing. During day time the LDR has low resistance and keeps the pin 12 of the IC1 high, preventing the IC1 from oscillating. When it is dark the LDR resistance becomes high and the pin 12 of IC1 becomes low and the IC starts oscillating, which indicated by the flashing of LED D3.The values of the timing components R1, R2, C4 are so selected that the out put pin3 of IC1 goes high after 8 hours. That means the high output drives the triac to switch on the lamp around 2’O clock. At morning, the LDR resistance drops and the pin 12 of IC1 goes high and stops the oscillation, making the lamp OFF. The switch S1 can be used to manually ON the lamp. The capacitor C2 prevents false triggering.

• Assemble the circuit on a good quality PCB or common board.
• The LDR can be general purpose LDR.
• The light sensitivity can be adjusted using the preset R6.
• The IC1 must be mounted on an IC holder.

S:circuitstoday.com

based on NE555 (IC1) & CD4017 (IC2) Dancing Light circuit

Here is a simple dancing light circuit based on NE555 (IC1) & CD4017 (IC2) .The IC1 is wired as an astable multivibrator to provide the clock pulses for the CD4017.For each clock pulse receiving at the clock input (pin14) of IC CD4017, the outputs Q0 to Q9 (refer pin diagram of CD 401) becomes high one by one alternatively.The LEDs connected to these pins glow in the same fashion to give a dancing effect.The speed of the dancing LEDs depend on the frequency of the clock pulses generated by the IC1.

• Assemble the circuit on a good quality PCB or common board.
• The ICs must be mounted on holders.
• The speed of the dancing LEDs can be adjusted by varying POT R2.
• The capacitor C1 must be rated 15V.
• Using different color LEDs could produce a better visual effect.

CD 4017 Pin configuration:
S:circuitstoday.com