Sense of Time tester circuit.

admin January 18, 2011 No Comments
Description. When S2 is ON ,the circuit here operates as an astable multi vibrator and the LED is lit for about o.1sec,flasing every 1.5 seconds.Since the human reaction time is more than this,you cannot catch it once it is seen o,by pressing S1.If your sense of time interval is good,and you press S1 with in that 0.1 sec,the discharging of C1 stops and then the lamp stays lit.you may change the ON and OFF periods by changing R1 and...
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UJT Organ circuit

admin February 16, 2012 4 Comments
Description. Here is the circuit diagram of a simple yet interesting mini organ based on UJT 2N 4891 (Q1). You can produce the desired sound by pressing each pushbuttons. You have also the option to set each push button to produce the desired tune you want. The circuit is based on a UJT oscillator who’s frequency is determined by the Presets R6 to R13 (one at a time) and capacitor C2. The transistor Q2 drives the speaker to produce...
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Scoring game circuit

jacky January 24, 2012 13 Comments
Description. A simple scoring game circuit that can be used for all occasions when a dice is needed.The circuit is based on a NE555 timer,a 74LS192 counter,a74LS247 decoder and a & segment LED display.The timer IC1 will produce the clock for the counter IC(IC2) whose frequency is determined by R1 and C2.When S2 is pressed the IC2 will count in up mode and when S3 is pressed the IC2 will count in down mode.The IC 3 will decode the...
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Touch Switch Circuit

admin October 30, 2018 33 Comments
In this project guide, we’re building a Touch Switch Circuit using NE 555 IC. As you know, NE/SE 555 is a very popular timer IC with multiple applications in different projects. A touch switch is basically a simple switching circuit activated upon a touch. If you’re new to 555 IC, please take time to read our beginners guide on 555 IC. Also, you can try many of our applications using 555 timer IC Description This is the circuit diagram...
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