Mains-Operated Light Star / Mohamad Fadzil Kamarudin and Mohd Nurul Faizal Jusoh

‘Mains-Operated Light Star’ is a simple circuit and easily constructed even by novice. Actually, this project is very suitable for used when a celebration day likes Hari Raya Aidilfitri, Christmas, Gong Xi Fa Cai and other celebration. Nowadays, it is not just used for celebration day but to make our domicile looks very pleasant. This circuit we present a straightforward fixed pattern flasher for three sets of lights. However this is not your usual 1-2-3 chasing pattern, this unit has six steps, 1 - 1 +2 - 2 - 2+3 - 3 - 3+1, and then repeated. If the three sets of lights are mixed on the tree, it is not that easy to see the pattern! On the prototype the speed was fixed to about three steps per second, but it would be a simple matter to put a control pot on the front panel to set the mood if required.
The triac outputs are driven from zero-crossing opto isolators, which virtually eliminate radio interference. The triacs are hard driven, making the outputs suitable for driving inductive loads such as the modern low voltage transformer driven light star (Christmas light). The outputs can drive loads of up to 3 Amps (or possibly even more if the PCB tracks are reinforced), making the unit suitable for driving higher powered outdoor lights.