Abstracts of Technical Articles From Bell System Sources (01 October 1931)

Proc. I. R. E., July, 1931. Trans. Electrochemical Soc., Vol. LIX, 1931. 684 ABSTRACTS OF TECHNICAL ARTICLES 685 1. For a particular BaO + SrO filament, the conductivity C was given by 1.71 X 104e 1.73 X 104 T + 5.55 X 10 - 3 e 0.62 x io< r 2. The current is proportional to the voltage only so long as the current is small; otherwise the products of electrolysis alter the conductivity. 3. Polarization currents are caused by the Ba and O which are produced by electrolysis. These currents decrease rapidly even at temperatures near 500° K., thus showing that Ba and O diffuse at low temperatures. Recent Developments in the Operation of Overseas Radio Telephone Service.3 F . A. COWAN. 

This paper outlines the status of the present overseas radio telephone services from the United States, discusses the disturbing factors affecting each type of circuit, and outlines the reasons why short waves have come to be considered the probable medium for future extensions. The causes of lost circuit time to these services are given in their order of magnitude as: adverse atmospheric conditions, operating adjustments, radio interference, line and equipment troubles, and unclassified causes. Adverse atmospheric conditions have been partially overcome by the use of directive transmitting and receiving antennas and automatic gain devices on the radio receivers. These arrangements, however, do not eliminate the lost time caused by magnetic disturbances directly in the radio path or by the phenomena known as selective fading.