Abstract: A portable alarm useful for indicating unauthorized entry at doors and windows includes a housing and a bell casing mounted in the housing with a clacker arm rotatably mounted within the casing and adapted to create an audible signal. A trigger arm is mounted within the housing, extending into to the bell casing and is biased against the clacker arm in a first direction. An actuator including an L-shaped arm and a pressure plate is pivotably mounted along an edge of the housing such that the lever arm extends outside the housing and with the pressure plate dimensioned so as to exert a pressure against the trigger arm in a second direction opposing the first direction responsive to a movement of the lever arm. The pressure plate is biased away from the trigger arm, until such time as a substantial force against the pressure plate overcomes the bias and forces the other end of the trigger arm out of engagement with the clacker arm, thereby effecting the audible signal.