Remote control switch on or off for home appliances

Associate this circuit to any of your home apparatuses (light, fan, radio, and so on) to make the machine turn on/off from a TV, VCD or DVD remote control. The circuit can be activated from up to 10 meters.




The 38kHz infrared (IR) beams produced by the remote control are received by IR collector module TSOP1738 of the circuit.
Pin 1 of TSOP1738 is associated with ground, pin 2 is joined with the power supply through resistor R5 and the output is taken from pin 3. The output signal is increased by transistor T1 (BC558).

The amplifier signal is given to clock pin 14 of decade counter IC CD4017 (IC1). Pin 8 of IC1 is grounded, pin 16 is joined with Vcc and pin 3 is associated with LED1 (red), which shines to demonstrate that the machine is "off."

The output of IC1 is taken from its pin 2. LED2 (green) associated with pin 2 is utilized to demonstrate the "on" condition of the apparatus. Transistor T2 (BC548) joined with pin 2 of IC1 drives hand-off RL1. Diode 1N4007 (D1) goes about as a freewheeling diode. The machine to be controlled is associated between the pole of the relay and neutral terminal of mains. It gets associated with live terminal of AC mains by means of normally opened (N/O) contact when the relay energizes.

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Simple Car Audio Amplifier Circuit

A straightforward low power car stereo amplifier circuit taking into account TDA 2003 is showed here.


The circuit utilizes low cost, promptly accessible components and it is anything but difficult to develop.
TDA2003 is an integrated car radio amplifier from ST Micro electronics that has a ton of good elements like short circuit protection for all the pins, heat over range level low harmonic distortion, low traverse bending and so on.

In the circuit given here each TDA2003 is wired as a mono amplifier working from a 12V DC supply. Resistors R2 and R3 shapes a feedback system that sets the amplifier gain. C7 is the input DC de-coupling capacitor and C5 couples the speaker to the amplifiers yield. C4 is utilized for enhancing the swell dismissal or ripple rejection while C1 and C2 are utilized for power supply filteration. C3 and R1 are utilized for setting the upper frequency cut-off. Network containing C6 and R4 is utilized for frequency adjustment and to avoid oscillation.

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