Building a Competition Buzzer Set, described the construction of a contest buzzer set. Additional reference material and parts are available, as described below: A kit includes an etched, undrilled printed circuit board, a programmed PLD, a 556 timer, miscellaneous mounting hardware, and a more detailed assembly manual. The kit costs $35.
Click here to download the full size of the above Circuit.
You will need about $25 to $30 in additional parts, available from standard electronics supply stores. I estimate about ten hours total assembly time is required, using this kit. If you are good at fairly simple electronics projects (or can talk to an electronics teacher or student into helping you) this is a good way to save money. The fully assembled and tested unit is just like the one pictured here. It comes with assembly and operations manuals. The unit looks good, is well constructed, and is durable (even when used by high school students). While it is not a commercial unit (we assemble and test it ourselves), it is a nice unit at an attractive price of $250. We do not keep these units in stock, so there is a delay in filling orders. This delay can be from a couple of weeks to a couple of months, depending on the availability of good student labor here to assemble them. A detailed assemble manual is available for plans for a modification to the contest buzzer set to add a large LED wall display to make the display visible to a large group. A schematic is also available. This was developed by Richard Levergood at Londonerry High School.
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