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There are many complicated electronic head or tail circuits have already been published. But this is a very simple circuit which uses a CMOS CD4017 counter IC.
This circuit is operated by touching the plate. To make the circuit more attractive, it can be modified to display a letter ‘h’ or‘t’ on the 7-segment common cathode LED display As e, f and g segments of the display are hard wired to the positive of the supply, high value resistors are used to maintain same intensity of all the segments. For LEDs and Segment’s protection used a 470R (ohm) resistor in series.
Components-
IC = CD4017
Resistor = 68ohm, 470ohm, 1K, 10M
D1 – D8 = 1N4148
LEDs (Different color)
7-Segment (Common-cathode)
9v Battery
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