On 2008-07-17, wrote:
On Jul 16, 5:20?pm, Andy Asberry wrote:
This project is for a ?student Quiz Bowl (think Jeopardy). Eight
handheld push button switches that turn on an led indicator (one for
each player) and energize a buzzer. It must also block all other
buttons so there are no simultaneous lights. Oh, and must be battery
powered.

[ ... ]

Use 8 dpdt 1v relays.All relay coils in series through the N.C.
contacts on each. When one button is pushed it energizes its coil
through a separate circuit with one of it's N.O. contacts with an
appropriate resistor as we're using a 12v battery. The other N.O.
contact operates it's LED and buzzer. Another pushbutton can be used
to reset.
Do I win the prize for simplicity?

It depends on just how close in time the contact closures might
happen. Relays are a lot slower than logic circuits, so a tie might
happen with the relays which would not be one on the logic circuit
versions.

Enjoy,
DoN.

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