The Enigma Puzzle Box


Introduction: The Enigma Puzzle Box

<-----UPDATED 2/3/12----->

I now have added a locking device in the form of a solenoid. When the amber LED lights up, the solenoid pulls in its plunger from the "lock" (a piece of MDF with a hole in it) and the box opens. I have updated the images to show this change.

So first off I apologize for not making a formal instructable. When I started this project all I wanted to do was jump right in and get it done. If you have any questions regarding the box's construction, coin slot construction, or circuit design, please leave a comment and I'll try to assist you as much as possible. Also keep in mind the construction of the coin slot is not necessary, you can remove it if you don't want to make it. Also I suggest you make the box, drill the holes, stain (not really needed, but its a nice touch), then solder in the electronics. Trust me, it will take longer but its worth it. Speaking of taking a long time, don not rush this project, take your time.

Materials Needed:
- 1 Rotary Switch.
- 16 SPST Toggle Switches.
- 1 Power Switch (also SPDT, but anything works).
- 1 Green LED 1.5vDC preferred.
- 6 VDC Solenoid.
- 1 Resistor 100 ohms +/-5% (Black, Brown, Black, Gold)*
    *The resistor was 15 ohms, but I changed it so now the LED's won't burn out. 
- 1 Amber (yellow) LED 1.5vDC preferred.
- 1 Battery Pack for 4 AA Batteries.
- 1 Box

- Plexiglass or other material to make coin slot.
- Stain
- MDF 1/8 for lock latch.

The "codes" are as follows (refer to circuit diagram):

Puzzle Setting 1 (Yellow Line): B1, D2, A3, A4.
Puzzle Setting 2 (Blue Line): A1, B2, D3, D4.
Puzzle Setting 3 (Orange Line): D1, C2, C3, B4.
Puzzle Setting 4 (Green Line): C1, A2, B3, C4.

Once all the correct switches have been flipped, the amber (yellow) LED will turn on.

Thanks for taking the time to read this instructable, all the best in future projects!



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34 Discussions


1 year ago

Would you be willing to make one for me? If so what's your cost?

Just install two of the stiches upside down on the box. That way when they are all switched "on", those two switches would actually look switched on, but they would be switched off.

Well I used the coin slot as a means of needing a certain coin to turn on the power.However I discovered that this can be by-passed quite easily. Your next best option would to use a key switch. Unfortunately, the only real way to ensure a secure locking box would be with a micro controller. Hope this helped.

Can someone offer me some assistance on the wiring of this box? I am having a little trouble. Please email me @ and I can send pics of what I've got and what it is or isn't doing. Maybe I'm just having trouble with the wiring diagram but it is frustrating me. :(

What are the specs for the rotary switch. they are all so confusing. how many pole, how many positions, how many pins?

Where can i buy it!!! please!

Looks nice. Maybe not a real security solution, but it's certainly a cool gift or conversation starter.

how does the key slot work? does it hit a switchor just electrically connect everything?

I will try soon. But onw question is on my mind. What kind of solenoid did you use? Push, Pull, both? How did you get it lock after powering off?

Sorry for my english, i'm french!

Another idea is to use SPDT switches instead. Then for each possibility, some switches need to be down and others up to open the box.

How much energy/voltage is needed to run this box? Considering using a solar panel instead of batteries.

1 reply

It really depends on what voltage the solenoid is. 6V is the standard from what I saw, not sure if you can find something lower than that. A better option would be to find a (or some) solar panels that can put out 9V.

If I would switch every one of them, wouldn't the box just open?

Also would this be a good substitute?