Electronic Circuits and Diagram-Electronics Projects and Design

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 R2 or C1 to suit your convenience. Circuit diagram with Parts list. Notes. Switch S1 can be a pushbutton switch. Switch…

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 reasonable sound output. For each pushbutton press the corresponding preset will be added to the circuit, and the UJT oscillates in…

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 count to display it on the seven segment LED display .Thats about the working of the circuit.The circuit is designed strictly…

Touch Switch Circuit using NE 555 Description This is the circuit diagram of a small touch plate controller using IC NE 555 .This circuit is ideally useful for making touch operated doorbells, buzzers,toys etc which when touched on the touch plate operates the relay for a preset time and the turns off automatically. This circuit is realized by utilizing the high input impedance of trigger pin of the 555 IC.When  the IC is triggered by the induced voltage of human body the output goes high for a time determined by R1 and C1.The transistor is used to drive the relay.The…