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Stupidly simple circuit question - answered.
OK, so I accidentally volunteered to make an X-factor type buzzer board for a school event.
Three switches. Throw each switch, in any order, a light comes on.
Throw the third switch, in any order, and a buzzer and/or fourth light comes on.
It's a simple circuit. Must be. Just a few transistors, LEDs and batteries.
But, I just cannot work it out!
I should be able to sketch it out in my sleep, but my brain will simply not cooperate.
I'd prefer to use a single DC power supply, up to 12V (multiple LEDs to make the lights brighter), but I have several I can use if required.
Dimensions are not important, I'll just change the lengths of wires.
But, can you help with the circuit?
>K<
Comments
11 years ago
Right, I've never watched X-Factor, but I think you want:
Each of three switches to light their own light independently.
All three switches to power a buzzer / 4th light?
Get three double-pole double throws, and wire like this.
L
Reply 11 years ago
>gives lemonie a vicious kick for coming up with a better idea and schematic before I was about to post another<
Reply 11 years ago
I was all ready to go for a set of self-latching relays...
Reply 11 years ago
I made it all pretty, with a three way AND gate and everything.
>mourns<
Reply 11 years ago
Hey, you can still post it, especially if it's all pretty.
Reply 11 years ago
If the switches trip the timer (monostable multivibrator) which trip the buzzer, you can set the duration of the buzz time.
Reply 11 years ago
Don't forget a monostable otherwise that buzzer's going to be going off FOR EVER and be really annoying :D
Reply 11 years ago
That's a very good suggestion.
Reply 11 years ago
If you want something with big red plastic single-push non-latching buttons that light-up and a master-reset, the question is still open...
L
Reply 11 years ago
I'm now waiting to find out my budget - latching DPDT push-switches are available on ebay.
Reply 11 years ago
Ooof! Urrrgh... (ow)
L
Reply 11 years ago
Can I recommend armor,pretty useful...
Reply 11 years ago
Of the pop-tab-maille variety?
(Let's have a discussion about the protective quality of aluminum as medieval armor!) :-P
Reply 11 years ago
That's one "age" missing from History... But the topic is around here somewhere (a person objecting to the armour on grounds of irresponsibility)
L
Reply 11 years ago
Gah, beat me by 3 mins, and with a schematic too!
Reply 11 years ago
I would have been a bit quicker, but I had to be sure of what the thing is supposed to do first...
DPDT - we think alike
L
Reply 11 years ago
Egad! The man's a genius!
I could even make that with clothes pages!
I knew it was simple, I just could not make it work in my head.
11 years ago
I just have to say that the competition is getting very stiff. Yall make a great committee.
Reply 11 years ago
Huh?
Expand, please?
Reply 11 years ago
So many people with good answers all trying to be there first.
11 years ago
I'm a little confused by the description - you mean like this (yes, I know it's messy, I did it in a hurry :P )?
Reply 11 years ago
Three judges, each with a switch.
When they have had enough of a contestant, they hit a switch and a light comes on.
When the third judge hits their switch, in addition to their light coming on, a fourth event (such as a buzzer) indicates that the contestant is no longer welcome on the stage.
So - three switches, each working one light.
A fourth device gets triggered once all three lights come on (the three lights can be lit in any order).
Is that clearer?
Reply 11 years ago
I know Lemonie already answered, but wouldn't it be easier to have switch one control a light, switch two control an other light, and switch three control a light and a buzzer? As in only switch three needs to be "switched on" for the buzzer to go off? As long as judge three goes last, it seemingly works the say way as Lemonie's suggestion.
Also, what's the school event? Talent show, spelling bee, science fair?
Reply 11 years ago
It's a talent show, hence the X-factorisation.
Reply 11 years ago
Ah, I see. I never watched the show, so I wouldn't know. Thanks.
Reply 11 years ago
Need three double pole single throw switch.
Use one pole from each switch to actuate each light, connect the second pole of each switch in series to actuate the fourth light.
Reply 11 years ago
Thanks!
Unfortunately, Lemonie beat you to it by three minutes.
Reply 11 years ago
Ahhhh, much, yes. :D Thanks.
11 years ago
Do you get the sense of being on the same level as students who also have homework to do this weekend before they go back...? (Like my brother who's got a load of marking to do)
I'll think
L
Reply 11 years ago
I've got a few weeks, but I have a terrible habit of getting distracted by new projects. I know that I have two other large projects on the horizon, plus I have a bit of a learning curve to climb at work in the next two terms.
Oh, and there's the marking...
Reply 11 years ago
Marking... having a few teachers in the family: I know.
L
11 years ago
Sorry, the instructables community doesn't like answering homework questions. :p
Reply 11 years ago
Ok... so you need:
AND gates