Does anybody know how to make secret knock detecting lock circuit.

For your (helper) information...I don't want to use the arduino.
It it possible to create this project without using the arduino?
If yes,can someone tell me how the circuit look like???
Really want to do this project. FYI, I know the arduino cannot be built (handmade)...that's why I really need to know whether this project can be created without using arduino???