This paper describes the receiving electronics built at the Bell Laboratories Crawford Hill facility at Holmdel, New Jersey to use the 19-and 28-GHz beacons on the COMSTAR satellites for propagation ...measurements. The receiving system accurately determines attenuation, differential phase, depolarization, bandwidth limitations and angular scatter of these signals produced by rain. This highly reliable system operates continuously and unattended; it automatically reacquires the beacon signals after dropout due to severe attenuation or momentary power outage. Correlations among strong and weak signal components are used to permit detection of weak cross-polarized signals during severe fading. Receiver noise bandwidths as low as 1.6 Hz are used. A high degree of phase stability is achieved in all circuits and components.
A 1966 compact van, converted to operate on LP-gas and evaluated under the federal exhaust emissions procedure, approached several definitions of a "pollution-free vehicle." Specific pollutant ...results were as follows: 1. The hydrocarbon and carbon monoxide levels of 126 ppm and 0.3%, respectively, were below the 1968 and 1970 emission limits. 2. Certain LP-gas fuel system designs promise to eliminate all evaporative losses. 3. The exhaust hydrocarbons were 70% less reactive than those in gasoline exhaust. 4. Aldehydes, a highly reactive class of exhaust compounds, were low. 5. Oxides of nitrogen were significantly higher with LP-gas because of operation at maximum economy mixtures and maximum power spark advance. 6. The use of a catalytic muffler and rich LP-gas mixtures produced very low oxides of nitrogen levels with other pollutants below the 1968 limits.
