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Small circuit for new guy

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Pysiek

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Hi folks
I want to build a small system that will detect which circuit was closed first. I'm not a electrical guy so I will try to explain as best as possible :).
Lets says I have two pair of hands and a box with 9V battery in it and two bulbs. One pair of hands is connected to one bulb and second pair to the other. Now when the pointing fingers from each hand does not touch each other the bulb is not illuminating , but if you touch a those fingers the circuit will close and the bulb will light. Did I explain that good???
How to make one?
 

You need a flip-flop circuit that can trigger by one or the other input.
There are many versions, try google one you prefer.
 

This kind will not work. What I need is a circuit with one ground connection and two positive connections. I will put one circuit on top and one on the bottom. If the bottom contact touch each other Top LED will light up but if the bottom contacts touch each other first bottom LED will light up. This will be used to make sure both top and bottom are getting to touch at exactly same time.
 

Could you further explain your system? I think you could use simple switch on one of the fingers which would get pressed when the other finger is touching. But it would be quite easier to give a better suggestion if you could throw some more light on it.

Thanks,
MSBR
 

Pysiek said:
If the bottom contact touch each other Top LED will light up but if the bottom contacts touch each other first bottom LED will light up.
Click to expand...

Can you better explain this statement?

Maybe you should post a simple diagram of what is needed.
 

Please explain little more...For what application you are going to use this?
 

I'm really sorry for the late response. Email notification went to spam folder.
Let me try to explain it that way. Two LED lights. One marked "TOP" second one "BOTTOM. Two probes "-" and "+" for TOP LED and two probes "-" and "+" for BOTTOM LED.
Negative probes are stationary. Both positive probes moves together toward negative probes whichever the positive probe touch it negative probe first the LED will light up.
This is a circuit to make sure both positive probes are touching at exact same time to theirs negative probes.
Hopefully this is little bit more explaining :)
 

You can try this circuit:
The idea is that SW1/2 are the two probes. The one that makes contact first, fires and latches one of the SCR devices (U1/2) and robs current away from the remaining one so that will not be able to trigger You may have to experiment with the ratio values of (R2/3 and R4/5) depending on the type of SCR used to get the trigger thresholds correct.
 

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