Simple Electronic Lock Project

There are six (or more) push switches. To 'unlock' you must press all the correct ones at the same time,
but not press any of the cancel switches. Pressing just one cancel switch will prevent the circuit
unlocking. When the circuit unlocks it actually just turns on an LED for about one second, but it is
intended to be adapted to turn on a relay which could be used to switch on another circuit.
Please Note: This circuit just turns on an LED for about one second when the correct switches are
pressed. It does not actually lock or unlock anything!
Parts Required
• resistors: 470, 100k ×2, 1M • red LED
• capacitors: 0.1μF, 1μF 16V radial • 555 timer IC
• on/off switch • 8-pin DIL socket for IC
• push-switch ×6 (or more) • battery clip for 9V PP3
• stripboard 12 rows × 25 holes