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Need circuit design for quiz show


New Member
I am a primary school teacher organising a spelling bee, of which the final round is hopefully going to be like a quiz show on stage. 3 contestants must be able to hit a "button". The first person to hit, must switch on a light and a buzzer, and cut off the other 2. The light and buzzer must stay on just long enough so that the facilitator can see who is first. The design must be as simple and cheap as possible, and parts must please be labelled so that I will know what to buy (I am a language teacher, my science background is extremely limited). We plan to build a wooden box as container. About 100-150 children will attend the show.
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Well-Known Member
Game Circuits
This is about the simplest I've found. I've built several versions, but this basic one should do the trick for you.
The SCR's in mine are S401E...much smaller, but work well.
x4 Switches: Mini SPDT 3-Amp Momentary Pushbutton Switch - RadioShack.com
x4 Lamps: 6.3V/250mA Incandescent Flashlight Bulb (2-Pack) - RadioShack.com
x4 Lamp sockets: E10 Vertical-Mount Bulb Holder (4-Pack) - RadioShack.com
x1 Resistor: 1K ohm 1/2W 5% Carbon Film Resistor pk/5 - RadioShack.com
x3 SCR: S401E Littelfuse Thyristors - Diacs, Sidacs, SCRs & Triacs
x1 Zener Diode: 1N5234B Fairchild Semiconductor Zener Diodes
x1 Buzzer (across the upper left lamp): 85dB Piezo Buzzer - RadioShack.com
x1 Battery: 12V DC or Wall plug transformer rated at 12vDC and maximim current greater than 500mA

I think you will need to find a staff or faculty member, or parent that has the requisite skills to assemble it for you. If they understand the schematic and parts list they will probably qualify.

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