The problem of preventing unauthorised persons from accessing specific places has become an interesting research field. This study proposes a warning system to alarm the owner about any unauthorised attempt to access a secure gate. In the proposed system, the classic alarm circuits that use 555 timers or operational amplifiers are replaced with a simpler and more reliable electronic circuit that includes a small microcontroller chip known as a Programmable Intelligent Computer (PIC). The PIC is programmed to perform sense any touch and produce an alarm signal (buzzer sound), or to send a text message and/or phone call. Implementation of the system demonstrates the superiority of PIC-based circuit over rudimentary electronic circuits in terms of cost, size, complexity, reliability, and system updates.

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