Museum Watchdog

The Museum Watchdog is an analog security circuit powered by a standard 9V battery, designed to monitor the presence of a valuable display item. At the heart of the system is the CD4060 IC, which serves as a timing and logic controller, alongside a reed switch (S2) paired with a neodymium magnet. When the protected item is in place on display, the magnet is held in close proximity to the reed switch, keeping its internal contacts in a specific state. If an unauthorized person removes the item, the neodymium magnet moves away from the reed switch, causing its contacts to open or close. This physical shift changes the state of the input signal going into the CD4060 IC. Once triggered, the circuit activates its integrated audio-visual alert generator, supplying power to both a buzzer for an audible alarm and an LED (LED1) for a visual warning. Resistors and capacitors are integrated throughout the circuit to regulate voltage levels, set timing parameters, and ensure stable operation of the IC and indicator components. The entire circuit is assembled on a single-side PCB and housed neatly within an enclosure box, making it a compact, self-contained unit ready to be placed discreetly beneath or inside a display pedestal.