Abstract :
Following a general discussion of radio vs. submarine cable telegraphy, the work of the Radio Division of the Dutch East Indian Service is described. A chain of stations installed for this Service are considered; their location, equipment, and operation being described in considerable detail. The failure of the original contractor to furnish stations covering the requisite distances (which would have required six to eight times the actual available power) is critically considered. The choice of station location and certain details; e.g., precautions against earthquakes, are then treated. A description of the origin and nature of strays and their classification is given; together with a number of methods for their elimination. In this connection, the Eccles´ theory of a tropical thunder storm origin of all strays is disproven. There are described, in addition, some special methods of reducing strays, methods intended especially, however, for the elimination of undesired, powerful, and interfering signals. Strays fall into three classes, the origin, character, and mode of elimination of which are as follows: Type 1: Strays originating in nearby thunder storms, of short range, of periodic electrical character, audible as sudden and loud widely separated clicks, and eliminated by radio or audio frequency compensation circuits. Type 2: Strays associated with low-lying rain clouds, of very short range, of intermittent uni-directional electric character, audible as a constant hissing sound, and eliminated by the Dieckmann electrostatic shielding cage.
