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I'd like to make a locked box open when you play a chord on a nearby piano. Any suggestions for the remote-control lock? Answered

All of the remote control locks I've found are too robust. I just need a small lock I can hack into a wooden box.


on the inside of the piano set up a circuit so the outside edge of the hammer (the piece that strikes the wires) has a small amount of conductive tape on all the keys for the chord. Attach the wires so they hit the hamer in mid-swing. then these conect to form a long chain wire and this can be rigged to ether a remote signal generator or to a wired transmiter out side the piano. I can only think this would become an issue on the fastest of songs where the chord isnt ment to be struck.

If you mean an actual chord on an actual piano, you could probably tune a few frequency detectors for whatever number of notes in the chord. Can't whip up a circuit right of the top of my head, but if you look at some DTMF circuitry from the old days you could probably turn up some good ideas. If you mean just detect it physically on the piano, switches and any of the small processors should do.

get an electronic lock(keypad and combination) and a wireless doorbell (you know the ones that go off when a certain tone is played) and find out what tone it needs to go off. then take the speaker(s) out and take the keypad out except the button used to lock the lock and solder the two together so when the doorbell picks up the tone it unlocks the box instead of make noise.

that really is confusing if you need any more help just ask

use 2 arduinos a servo that turns locking mechanism 2 xbee modules a button(s) setup : setup ardsuino so that when button(s) gets press it send a bite of data over the xbees to anthor arduino inside the box ,so when it recives the data the servo turns the lock, to unlock the box

Good idea, but I think Xbees are overkill for this project. Sparkfun (for instance) sells small radio transmitters... you could get a pair for ~$10. Also, you might be able to get away with one Arduino if you can manage to get the radio to transmit, for instance, a pulse, based off of a 555 timer (or maybe a simple capacitor/resistor pair.) Instead of looking for a specific signal, just look for something being transmitted at that frequency. When your receiver gets a signal, the arduino moves the servo.