In the buzzer round of quiz contests, the question is thrown open to all the teams. The person who knows the answer hits the buzzer first and then answers the question. Sometimes two or more players hit the buzzer almost simultaneously and it is very difficult to detect which of them has pressed the buzzer first. In television shows, where the whole event is recorded, the actions are replayed in slow motion to detect the first hit. Such slow motions are possible only where huge funds are available to conduct the show.
For this reason, buzzer rounds beginning for quiz contests held in colleges. This project is useful for a 5-team quiz contest, although it can be modified for more number of teams. This system is sensitive. The circuit can detect and record the first hit contestant among all the contestants that may appear to be simultaneous. We have designed the circuit using an ATmega328P microcontroller, which scans the input from push buttons and displays the corresponding number on a computer display. It is a simple circuit with the minimum number of components and without any complexities. Even though this system is designed for only for 5 teams, more teams can be added.
Step 1: Block Diagram
The project has 3 modules
Power Supply: The power supply is a wall adapter which converts 220VAC to 9VDC. The power supply will provide power to the Quiz buzzer which will have a voltage regulator that supplies 5V for the rest of the circuit. The maximum current draw from entire circuit needs to be less than 1 Amp so that it does not exceed the maximum current that the power supply can provide.
Microcontroller Unit: The microcontroller will be ATMEGA328. It has an operating voltage of 5v. There are six analog input pins and 14 digital input/output pins. The Arduino Uno also has a 16 MHz crystal oscillator and USB a connector to interface with a computer. The microcontroller receives signals through both analog and digital inputs from external buttons. ATMEGA328P is the brain of Quiz buzzer which controls and organizes each and every event. It stores the name and time at which the participant has entered the buzzer in its database.
Arcade Buttons: Quiz Buzzer has 9 Arcade buttons, 5 button’s for opponent’s and there are 4 input button’s on the questioner’s side. The START button which specifies the beginning of the timer. STOP buttons signify the end of the timer, Buzzer pressed between START and STOP will only be considered. Microcontroller stores the player name’s in the same sequence as the buzzer is pressed. The CORRECT button is pressed when the player answer’s the question correctly The INCORRECT button is pressed when the answer is wrong and opportunity to answer the question goes to the next successive player’s and so on. Arcade Button’s work on a simple methodology, when the button is pressed it connects Digital read pin to Vcc else it is connected to GND.
Display Unit:The Computer will run the Quiz Buzzer software coded in Python which will communicate with the microcontroller through the USB interface. It will need to interpret and analyze the data sent from the microcontroller. The reaction time of each player will be displayed on the computer.
Step 2: Implementation
The circuit is designed and tested as soon as the block diagram is implemented. Changes are updated for designing the PCB layout.
Step 3: Demo Video
You can find more about the project here: (includes Arduino Code and PCB layout as well )
Github Link: https://github.com/Prathamanchan/QBuzz