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magic key

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Dr_Doggy

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hi, i want to be able to activate a circuit with a relay attached to a switch, but i don't want the relay to close until the second or third time i press the button (within X amount of time), whats the easiest way to do this?
 
Easy is relative, what's your experience? You can do this with discrete digital logic and a simple timer, a micro controller, or analog timer components.. If you have no knowledge of any of this from the start there is no easy way to do it, it's going to take effort =)
 
Your question is not real clear. Second or third time? Is it 2 or 3 or a random choice between 2 and 3? One approach might be break it into two parts. A counter (to count the 2 or 3 toggles/presses) and a delay circuit to delay and close your relay, then tie them together. Myself, I would use microcontroller. But this applies to my knowledge (as Sceadwain states) and being lazy. :D
 
Here's a circuit:

CombinationLock4013.gif
**broken link removed**
 
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amazing circuit, i wondered how those things worked, but i noticed that keying " 2,3,3,6,6,6,9" would work and so would keying 2 36363636 9 would also work, i could use a few AND or OR gates though to fix that issue right??

but that delay circuit at the end i think could help alot, but how would i arrange D1,D3,C2,R12 and the solenoid to use with a NPN transistor?
 
What does it matter if two combinations work out of a possibility of a few hundred. You would have to see if you can get an "opposite output" for an NPN transistor.
 
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that part would be easy though with a NOT gate, but how would that delay circuit circuit look if it were for NPN?
 
The 4013 already has an inverted output as Q bar (pin 2) so use this. Just mirror-image the output transistor and use an NPN. The delay components come off pin 1
 
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