ABSTRACTS 751 



and by hand tailoring (special filters, etc.). With the general increase in 

 the usage of radio communication, however, the amount of potential inter- 

 ference is greatly increased. This paper will be concerned principally with 

 the v.h.f. problem. 



There is generally a large difference between transmitting and receiving 

 power levels. As a result, spurious radiations, spurious responses, and lack 

 of sufficient receiver selectivity may in many instances cause interference. 

 Situations are described in which such interferences are likely. 



In mobile systems interference can occur if the interfering station is close 

 enough to ''capture" it from the desired signal. This, in turn, depends upon 

 the selectivity and spurious response of the receiver and the amount of 

 spurious radiation from the transmitter. The problem can be approached 

 in a statistical manner. 



The types of spurious radio behavior which are common causes of inter- 

 ference are discussed. Sample measurements are given to illustrate the 

 relative magnitude of the various modes of behavior. Formulas are given 

 which permit computation of the frequency of the disturbances. A method 

 is described for making charts suitable for a given type of equipment from 

 which the spurious frequencies can be read directly as a function of the 

 operating frequency. 



