Miniature Meteorological Balloonsonde.
Curtis D. Motchenbacher · 1977
The purpose of this program was to demonstrate that it is possible to build a light-weight miniature meteorological sonde (minisonde) which can be borne aloft by a 30-gram latex balloon. During this program, 85-gram minisondes were built and successfully launched with 30-gram balloons. The program was broken down into two parts- the assembly of five minisondes and the launching/data reduction for these minisondes. The construction of a small, light-weight minisonde requires that new miniature sensors and high-efficiency electronics be used. For temperature measurements, the standard rod thermistor was selected. For humidity measurement, the conventional VIZ carbon hygristor was used. For pressure measurement, a Honeywell silicon diaphragm barometer was used. To commutate between the temperature, pressure, and humidity sensors and encode the meteorological data measurements, a set of meteorological electronics was developed using commerically available integrated circuits. A special light-weight telemetry transmitter providing an output of 1/2 watt at 400 to 406 megahertz was designed and constructed. Power for the transmitter and minisonde electronics was provided by a small flat disc battery using lithium electrochemical technology. Three minisondes were launched using 30-gram latex balloons and rose to an altitude of greater than 15,000 feet at a rise rate of approximately 600 feet per minute. During the flight, temperature, pressure, and humidity data were successfully telemetered back to an FM receiver located on the ground. (Author)