Abstract: An integrated precision humidity and temperature control system of research laboratory quality is disclosed in which air flow, water spray and refrigeration apparatuses are sequenced automatically by solid state controls linked in a cooperative manner. Very stable and precise relative humidity and control air temperature constancies are maintainable.

Abstract: An environmental chamber for testing objects, such as electronic components under climatic conditions, in the range of 80.degree. C. to 150.degree. C. and relative humidities in the range of 70% to 95%. The test chamber is pressurized and supplied with moisturized, heated air to obtain the desired climatic condition, the climatic condition being maintained by surrounding the test chamber with an insulated housing. A double door arrangement is provided to effect a pressure seal and for isolation of the test chamber from any appreciable heat loss.

Abstract: A property protection alarm system is disclosed for protecting property against unauthorized intrusion and the like. The alarm system includes a numeric key board and a code combination logic circuit for arming an alarm energization circuit in response to the proper entry of a predetermined numeric code in the numeric keyboard. This predetermined code must be entered within a given period of time determined by the code combination logic circuit. In addition, the numeric key associated with the last digit of the predetermined code must be depressed for a given period of time as also determined by the code combination logic circuit. An exit delay circuit is connected to the output of the code combination logic circuit for delaying the arming of the alarm energization circuit in order to permit an authorized operator to leave the property without energizing the alarm. The alarm energization circuit is connected to a sensing circuit for sensing any intrusion of the property.