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Quiz Game Circuit

Quiz Game Circuit

Quiz Game Circuit

Hi there!

i was wondering if anyone had a complex circuit diagram for a Quiz Game.  who ever presse the buzzer first, the opponents buzzer/light is blocked, and is then automatically reset.  i would like it if the circuit was used with logic, rather than micro-electronics.  

can anyone help me?


RE: Quiz Game Circuit

I designed a 4-player system that used a 74LS125 tri-state buffer. Input the momentary pushbutton switch signals into the '125. The output of the '125 that activates can toggle a flip-flop that drives a buzzer/light to indicate which player is trying to answer, and is also used to disable the '125 so no other player can buzz in. Use the appropriate 4-input logic gate to create a signal that disables the '125 from a single '125 output. Don't forget to decouple the Vcc and include a clear momentary pushbutton switch to restore the system to normal. This is expandable to work for two teams of four players each by doubling the '125s and using an eight-input logic gate to disable both of them. Of course, if you don't want the fun of building the circuit from my verbal descriptions, you can always follow the schematics in the link above. I enjoyed the project because I did the work myself from a few reference books.

RE: Quiz Game Circuit

Thank you guys.....

RE: Quiz Game Circuit

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