  The increasing rate of crime, attacks by thieves, intruders and vandals,
despite all forms of security gadgets and locks still need the attention of
researchers to find a permanent solution to the well being of lives and
properties of individuals. To this end, we design a cheap and effective
security system for buildings, cars, safes, doors and gates, so as to prevent
unauthorized person from having access to ones properties through the use of
codes, we therefore experiment the application of electronic devices as locks.
However, a modular approach was employed in the design in which the combination
lock was divided into units and each unit designed separately before being
coupled to form a whole functional system. During the design, we conducted
Twenty tests with the first eight combinations being four in number, the next
seven tests being five and the last five combinations being six. This was done
because of the incorporation of 2 dummy switches in the combinations. From the
result obtained, combinations 8, 11, 13 gave the correct output combination.
However, 8 being the actual combination gave the required output. The general
operation of the system and performance is dependent on the key combinations.
The overall system was constructed and tested and it works perfectly.
