Transistor as a switch.. Please help

[sTImpY2487]

Hello... Im new here, i just want to know how can i make a transistor connection with 3 LED as an output and three switch input? Wherein if a person press one switch the one LED will light up and the other will be disabled even if the person press another switch the output LED of that switch will not light up. and theres a master reset button.

 

[duffy]

Google "game show indicator lights", there are several circuits for it on the web.

 

[duffy]

The light's running on DC. Comes from that bridge at the upper-right. You can run a filament bulb on AC or DC.

The "lockout" effect comes from the load developing a voltage across that 5 watt series resistor at the bottom (which also provides the voltage for that relay). That sends all the SCR cathodes up to 5V which is the same as the trigger voltage. At this point the other triggers become useless because there's no differential voltage between gate and cathode.

 

[sTImpY2487]

....

Thanks for the reply duffy, ill work on it right away... Just wanna ask, whats the other symbol. not really that good at familliarization of schematic symbols, always rely on datasheets. LOL.. ^_^ please see the image below.

ImageShack - Image Hosting :: elecs4.jpg

 

[KMoffett]

sTImpY2487,

A low voltage DC version of the concept in Duffy's post : Game Circuits

Ken

 

[sTImpY2487]

K moffet

thanks.. ill try this one first.. its more simple, but i think its almost the the same with duffy. But yet the circuit diagram you gave have no specifications of the components, i mean the product code of each component. but thanks anyway.

 

[KMoffett]

The manufacturers Part# are listed on the first schematic:
SCR: S2006L
Bulb: KPR112
Zener diode: 1N4739
resistor: OK, none there, but any 100Ω 1/2W will work.

These are ones I've used, hope this helps:

Mouser electronics:
SCR's: S401E
Zener diode: 1N4739A-TR

Radio Shack:
Resistors: 100 ohm 1/2W 5% Carbon Film Resistor pk/5 - RadioShack.com
Bulbs: 6.3V 250mA Incandescent Falshlight Bulb (2-Pack) - RadioShack.com

ken

 

[duffy]

Thanks for the reply duffy, ill work on it right away... Just wanna ask, whats the other symbol. not really that good at familliarization of schematic symbols, always rely on datasheets. LOL.. ^_^ please see the image below.

ImageShack - Image Hosting :: elecs4.jpg

That's just the relay contacts. You can leave that whole relay and it's diode out of the circuit if you don't have a use for it. It's in there to trigger a bigger light or something that goes on when any player hits a switch.

 

[duffy]

Would that relay be able to also reset the game if you wanted. Let's say DbpDt and use both contacts ?

I'm not try to high jack. if so, I'll remove this one.

kv

Wait, kv, this isn't hijacking, don't remove your post. You could use it to reset the device, yes, but it would just click on and off so fast it might not even blink the light.