Abstract: In a system and process for heating and cooling a house, circulated and/or intake air is passed through a system which utilizes low intensity and readily available geothermal heat capacity to heat or cool such air. The ducts of the system have an internal configuration and size that provides for relatively low velocity and correspondingly low pressure drop through such ducts yet provides air flow patterns that have sufficiently high air velocities adjacent the interior surface of the duct to provide extremely good heat exchange between such air and the interior surfaces of the ducts to utilize the low intensity temperature differentials provided by the earth mantle at only moderate depths adjacent a house in any of a great variety of areas.

Abstract: A master control unit is placed for operation at each of several radio stations covering large area zones. A distinct audio triggering frequency is provided for each of several defined smaller zones in the large area zones. On notice from the National Weather Bureau or other appropriate agency, as Sheriff's Office, the operator of the master control unit selectively triggers radio frequency receiver assemblies to automatically connect to disconnected loudspeakers in such radio frequency receiver assemblies in any one small area zone, any combination of such zones, or all zones in its watch area to then automatically cause audible notice of any immediately needed warning affecting only that small area zone or any combination of such smaller area zones.