Last Christmas I built a Quiz Buzzer System for my mother. She is a big fan of television quizzes and love to organize some with her friends and family. The particularity of this project is that you can choose your team buzzer sound from a list of more than 30 digital sounds.
The system is composed of a main console, 8 buttons, a power supply and a set of telephone cables. The core of the console, built in a plastic project box, is made of an Arduino Duemilanueve micro-controller coupled with an Adafruit wave shield. The 8 buttons are made out of small project boxes and arcade buttons, again from Adafruit. The buttons are connected to the main console using telephone jack and cables.
For this project I am using all the IO available on a standard Arduino board. I even have to use the pins #0 and #1 to achieve my goal. To drive the buttons LEDs I am using a 74HC595 shift register chip. To drive the control panel LEDs without using additional IO pins I am using two 74LS32 OR gate chips. Finally, to drive the cluster of LEDs I am using a L293 driver chip.
To change your team buzzer sound you maintain the main console button pressed and push any button of the team who wants to change it’s buzzer sound. Every tie you push the team button, the next sound in the list is played. When you find the perfect sound for your team you release the main console button and voilà …
You can find the Arduino source code on my Github at https://github.com/pchretien/quiz.