DIY ultra cheap combination lock

Today I am back with another project called DIY ULTRA CHEAP COMBINATION LOCK CIRCUIT. A combination lock is a type of locking device in which a sequence of numbers or symbols is used to open the lock. There are two types of combination lock available, Analog and digital. In analog type the sequence may be entered using a single rotating dial which interacts with several discs or cams, by using a set of several rotating discs with inscribed numerals which directly interact with the locking mechanism. On other hand digital locks are using keypads to enter the code. Now we are going to make a digital combination lock circuit using simple components. yes I know I can use an AUDINO. But my goal is different”

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