Design & Construction of 8 Channel Buzzer Using Microcontroller

Quiz buzzers are used often at places like educational institutions where it is required for game shows and also in live quiz competitions broadcasted via television. A quiz buzzer allows any user to press the switch quickly in response to a question posed during competitions that are conducted in schools and colleges. The pressed switch gives a buzzing sound or alarm for some duration of time and the reaction time is very small. Buzzer can also be used in different applications such as annunciator panels; electronic metronome microwave oven and other house hold application. 
Conventional systems require human intervention to decide which team has pressed the button and this system can be erroneous and even biased. Another problem arises when two members pressed the button at a negligible interval and it is difficult to guess who has pressed the buzzer first. Here we designed an automatic quiz buzzer system such that when more than one team presses the buzzer, the delay is accurately taken into account and number is displayed.