[ad_1]
We designed a Quiz Buzzer circuit that can be used for eight players/teams in quiz competitions organized by schools or colleges.
Normally, quiz circuits are designed with microcontrollers, but this simple circuit does not use any microcontroller. The heart of this circuit is a priority encoder, 74LS373. The author’s prototype built on a breadboard is shown in Fig. 1.
Components Required
| Parts List | |
| Semiconductors: | |
| IC1 | -LM7805, 5V voltage regulator |
| IC2 | -74LS373 priority encoder |
| T1, T2 | -2N2219 NPN transistors |
| BR1 | -1A bridge rectifier |
| LED1-LED9 | -5mm LEDs |
| Resistors (all 1/4-watt, ±5% carbon): | |
| R1 | -1-kilo-ohm |
| R2-R10 | -5.6-kilo-ohm |
| R11-R18 | -100-ohm |
| Capacitors: | |
| C1 | – 1000μF, 35V electrolytic |
| Miscellaneous: | |
| CON1 | – 2-pin connector |
| S1-S8 | – Push-to-on switches |
| X1 | – 230V AC primary to 9V, G39 500mA secondary transformer |
Quiz Buzzer Circuit
Fig. 2 shows the circuit diagram for the quiz competition buzzer.
WHERE IS THE REST OF THIS ARTICLE’S CONTENT?
This is PREMIUM content, which means that only
REGISTERED users of our website can read it, by logging in.
If you ARE a registered user, CLICK HERE to login.
Else, CLICK HERE to register for FREE!
[ad_2]
Source link
