This LED-based message display isbuilt around readily availble, lowcostcomponents. It is easy to fabricateand makes use of 3mm red LEDs. Atotal of 172 LEDs have been arranged todisplay the message “HAPPY NEW YEAR2004.”The arrangement of LED1 throughLED11 is used to display ‘H’ as shown inFig. 1. The anodes of LED1 through LED11are connected to point A and the cathodesof these LEDs are connected to pointB. Similarly, letter ‘A’ is built using LED12through LED21. All the anodes of LED12through LED21 are connected to point A,while the cathodes of these LEDs are connectedto resistor R8 (not shown in thecircuit diagram). Other letters/words canalso be easily arranged to make the requiredsentence.The power supply for the message displaycircuit (Fig. 2) comprises a 0-9V, 2Astep-down transformer (X1), bridge rectifiercomprising diodes D1 through D4,and a filter capacitor (C1). IC 7806 (IC1)

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