I'L 1 RA -SHORT- 1 1 '.I I 'E 1 R. 1 XSMISSIOX PHENOMENA 



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level; the bench slope, and a strip of woods lay immediately in front 

 of the field and on the transmitter side. Covering the entire field was 

 an irregular "fringe" system, the fringe spacing varying something like 

 one to four times the wave-length (4.6 meters). By driving the re- 

 ceiver car back and forth across the field a particularly high field 

 intensity line was located and marked for perhaps a hundred yards 

 (91.5 meters). The car was then placed exactly on the line and the 

 receiving set meter carefully watched for any change in the location of 

 this line. No noticeable shift occurred, and the line was checked on 

 the following day and again several days later. A car movement of 

 one foot (30.5 centimeters) was immediately detected by the receiving 

 set meter. It was necessary each time to drive the car in straight 



Fig. 4 — Map of Holmdel region. 



parallel lines since the polar receiving characteristic of the combination 

 of metal car body and radio receiver was not a circle. Opening a car 

 door immediately altered this characteristic. This high field intensity 

 line was not a straight line, being a bit "snaky," and it suffered a shift 

 varying from 2 to 15 feet (0.6 to 4.6 meters) when the transmitting 

 wave-length was changed from 4.6 to 3.7 meters. 



These standing wave patterns subside on cleared hilltops and need 

 not therefore seriously affect actual ultra-short-wave channels. They 

 have not been studied by us at distances much exceeding 10 miles (16 



