Pyroelectric Fire Alarm

Ordinary fire alarm circuits uses diode sensors to detect fire presence. But a pyroelectric fire alarm circuit described here is an ultra-sensitive fire sensor that uses direct piezoelectric property of an ordinary piezo element to detect fire.

FM Booster Circuit to Receive Far Away FM Stations

This is a low cost FM booster circuit to receive far away fm stations clearly on your radio in your local area. The circuit diagram of FM booster consist of a common-emitter tuned RF preamplifier wired around VHF/UHF transistor 2SC2570.

Solar Charger Circuit For Lead acid, Ni-Cd And Li-ion Battery

The solar panel based charger described here is capable of charging Lead acid, Ni-Cd And Lithium-ion batteries. This circuit diagram is designed for a solar panel which is capable of delivering 5W power. The solar panel outputs 16.5V. It can deliver a current of 300-350 mA.lead acid, Ni-Cd and Li-ion. The lead-acid batteries are commonly used in emergency lamps and UPS.

LM317 Constant Current Battery Charger Circuit

The LM317 is an adjustable three-terminal positive-voltage regulator which can be used as a constant current source for battery charging. This regulator IC is capable of supplying 1.5 A over an output-voltage range of 1.25 V to 37 V.

Touch Sensitive Musical Bell With Timer

This circuit diagram is a UM66 based touch sensitive musical bell. The circuit is built around CMOS IC CD4011 and popular melody generator IC UM66. The circuit contains a pair of touch plates. When these are bridged by hand for a moment, the um66 starts making music. Moreover this circuit has a timer which stops the music automatically after a few seconds. This makes the circuit, an automatic music bell.

Computer Hardware Powerpoint Presentation

Here's a powerpoint presentation ppt about various computer harwares might useful for Engg./Diploma students. The presentation includes 52 slides and contains various tyspes of images and medias.

Powerpoint type : MS powerpoint 2003 (ppt)

Presentation Includes:

Rotation Sensor Circuit Using 555

The picture shows the circuit diagram of a rotation sensor that can turn on a device like motor or buzzer while the circuit assembly rotates. The circuit is based on basic 555 timer operation.