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Electronic Box Lock Help!? Answered

OK so I would like to use a solenoid to unlock a box from the inside, problem is the electronic circuit I designed inside the box operates on 3 vdc and as far as I can tell most solenoids operate on a voltage of 6-24 vdc. Is there any way to make a simple driver circuit for a solenoid so it can operate on 3 vdc? 

Below is a copy of the box's circuit so far. I would like the solenoid to be in parallel with the "puzzle solved LED."


There's no reason why this couldn't work with 6V. You also MUST PUT A RESISTOR IN SERIES WITH THE LEDs.


OK, thanks. what Ohm rating should the resistor be? The LEDs draw about 3 volts.

Things don't "draw" volts, they "draw" current...How many milliamps do they need to light up.

That's quite a high voltage for yellow/green leds. I would have expected more like 1.8V, and around 20mA of forward current. On 6V, 150 Ohms should work OK


It looks to me like you could unlock it just bu turning all of the switches to on.

Yea its is possible to open it by flipping all switches. I've built in a key slot so that it will only turn on if a certain key is inserted.

Turn some of the switches so that up is off and some so that up is on and then you have to know the combination to open it up.

Ah I see, good idea, I am not sure if I can do it though,,,Some of the wires connecting the switches are tight as it is.