Each sector is of the order of 12° in width. Dot and dash signatures 

 are radiated in alternate sectors . Smoothly varying the phase of antennas A 

 and C with respect to B makes the equi signal lines rotate at an almost uniform 

 rate through one sector during the keying cycle . Rotation ceases at the end of 

 the cycle, and the pattern returns to its original position for the next cycle. 



b. Receiver 



The observer uses a standard communications receiver with an omni- 

 directional antenna and hears the equisignal once during each keying cycle . The 

 angular position in the pattern sector is determined by listening to the signal 

 and counting the dots or the dashes before the equisignal, which always appears 

 as a continuous tone. A continuous signal and an identification code are trans- 

 mitted between the keying cycles . 



At the end of each keying cycle all the equisignal lines momentarily 

 disappear. They reappear in their initial positions at the beginning of the next 

 cycle and resume rotation as described. 



Each transmission cycle lasts for a time period whose length de- , 

 pends on whether the German or English cycle is being used. Some of the 

 important transmission characteristics are listed in Table IV -2 . 



TABLE IV -2 



TRANSMISSION CHARACTERISTICS 



Consol Consol Consolan 



German Cycle English Cycle American Cycle 

 Transmitted Signal Seconds Seconds Seconds 



CaU Sign and DF Signal 55 26 7.5 



Silent Interval 2.5 2 2.5 



Directional Transmission 



(Dots or Dashes A n/sec) n = 60 n = 30 30 ' 



Silent Interval 2.5 2 2.5 



It is evident, for example, that with a sector width of 12° and a German keying 

 cycle utilizing 60 dots or dashes per sector, the resolution per sector is of the 

 order of 1/5°. 



38 



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