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BELL SYSTEM TECHNICAL JOURNAL 



Record "F" is that of a tangential run along the old Matawan- 

 Morganville road. Starting In the town of Matawan, with houses and 

 trees about, the pattern Irregularities subside slowly, as these objects 

 decrease In number, up to 0.95 mile. At 1.26 miles a rise of ground to 

 the left (transmitter side) is covered with an orchard. Apparently the 

 unfavorable slope is more potent than the trees in reducing field in- 

 tensity, as the field falls and rises more in accord with this land rise 

 than with the orchard. At the end of the record some large old maples 

 on the transmitter side of the road roughen up the pattern very 

 markedly. 



Record " 6"' is a short run taken on a private road where the car was 

 run In from a cleared field into woods. 



Field Fluctuations from Moving Bodies 



It is well known that the motion of conducting bodies, such as 

 human beings, In the neighborhood of ultra-short-wave receivers pro- 

 duces readily observable variations in the radio field. This phe- 

 nomenon extends to unsuspected distances at times. Thus, while 

 surveying the field pattern in the field described above, we observed 

 that an airplane flying about 1500 feet (458 meters) overhead and 

 roughly along the line joining us with the transmitter, produced a very 

 noticeable flutter, of about four cycles per second, in the low-frequency 

 detector meter. We then made a trip to the nearby Red Bank, N. J., 

 airport, distant about 5§ miles (8.8 kilometers) and observed even more 



20 

 18 

 16 



Z 



o 



300 200 100 100 200 300 



DISTANCE OF PLANE FROM TRANSMITTER OR RECEIVER - WAVELENGTHS 



Fig. 7 — Beat frequencies produced by reflection from a moving airplane. 



