Injured person alarm and location equipment - has sound generator supplied through resistance short circuited to give loud alarm

摘要

The alarm and location equipment is for a sick or injured person isolated in a building. Each person to be protected carries a radio transmitter functioning automatically after a preset time lag under the effect of a switch sensitive to changes in orientation. Controllable temporary muting and/or initiation devices can be included, each transmitter having an audible alarm controlled by the same switch. Signals from the transmitter control alarm lights and/or bells or a number of fixed receivers with flashing lights connected to a central alarm panel. The audible alarm of each transmitter is a squeaker supplied by the switch either directly of via a short time delay and through a resistance. The resistance is short-circuited on initiations of the radio transmission, so that the squeaker acts first as a soft pre-alarm warning and then as a loud alarm.