Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[REK636]

I'm trying to find somthing to take up my 3.5 panel. I'm looking at this circuit and im thinking about using it to turn on a computer. Would putting in a optocoupler work insted of the relay and can you tell me how it works. I'm goint to use a 9v battery so I dont have to run a second cord.

http://www.free-electronic-circuits.com/circuits/electronic-combination-lock.html


Why is it grounded after the switches?

I have no electrinic experience and I would like to try somthing and learn hopefuly not from a mistake.

[viridius]

That's kind of neat, but it would probably be easier to use a 4017 or something.  An optocoupler would work in your application.  The grounding after the switches is to pull them low and force a logical "0" when they aren't pressed.  Otherwise, you could get false triggering.  I have a working schematic for a combination lock with a dial if you're interested.

[REK636]

sure...dont know whayt you mean by dial. you me a selector dial?

[viridius]

More like a combination lock you'd find on a gym locker or something.

[REK636]

how does that work with one dial and then you select with a button or with multiple dials ?

the one dail  thing might work insted of using several push button switches on the pannel giving me some room.

[viridius]

Sorry I've taken so long, it's been kind of busy around here.  My original prototype had a RC delay circuit that would only "enter" the number after a few seconds had passed.  So: spin the dial to a number, wait a few seconds, spin the dial to another number, wait a few seconds, spin the dial to the last number, wait a few seconds and the output signal of the lock goes high.