Photoelectric counter / Mohd Rafi Shaari and Mohamed Roshimi Md Shahor

In today’s world, the term digital has become part of our everyday vocabulary because of the dramatic way that digital circuit and digital techniques have become so widely used
in almost all areas of life. In our project paper is basically design of one many project that used in today. It’s about the ‘Photoelectric Counter” that a working prototype be built f a photoelectric counter, for which there maybe a market. If it is determined that such a market exists, the project could be mass-produced.
There are many occasions when various objects, parts, products and even people must t: counted. In a factory, as unit move past on a conveyer belt there is a need to keep a. count. When people enter a room or store, ii is often desirable to know how many are present at any time.
The photo-electric counter circuit described here counts up every time that the shinning of fight on a photo resistor is interrupted. When the count reaches 999, the counter restart; at GOO and sends an overflow pulse. This pulse can be used to add move digit, trigger another circuit, cr sound and alarm. The counter can be reset or halted at any time.