On Wed, 16 Jul 2008 19:20:35 -0500, 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.

Just to clue you in on my capabilities, the last course I took in
electronics was for tube radios. I can solder.
....

This is a fairly common question and you can see some really weird
solutions if you google for Jeopardy switches lights circuit.

If you don't want to use a PLC like Karl suggested, or a microprocessor,
as many would suggest, then see http://i18.tinypic.com/4uenm6a.jpg
a simple and straightforward circuit as discussed in following URL:
http://sci.tech-archive.net/Archive/.../msg03089.html
This solution uses about 9 parts per station, plus a bunch for the main
panel. It depends on SCR operation to interlock the stations, so only
the first-button-pressed station lights and stays lit.

Also see relays methods http://www.flickr.com/photos/65791337@N00/498510014/
and http://www.desmith.net/NMdS/Electronics/Jeopardy.html . The former
link is mentioned in informative thread about jeopardy-game-design-requests,
http://www.cervo.biz/ElectronicsDesi...est-66487.aspx
which is copied from the sci.electronics.design newsgroup where
jeopardy-game-design-requests are a FAQ.

Two of the weird ways:
http://electronicdesign.com/Articles...rticleID=10854
uses flipflops etc to arbitrate every pair of stations, so would
require about 28 FF's for 8 stations, and a mess of wiring.

http://www.discovercircuits.com/H-Co...cnprogress.htm (near
the middle) says "... they press the button ... a powerful xenon
flash is produced by the box ... A light detector in each of the
boxes detects the light flash and temporarily disables the [other
boxes]..."

-jiw