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BELL SYSTEM TECHNICAL JOURNAL 



on certain days for hours shown operative on these curves one or more 

 might be entirely out of service. This chart indicates the tremendous 

 advantage in employing a number of separate wave-lengths varying a 

 good deal in their characteristics and choosing at any one time that 

 wave-length which is giving the best performance. 



Fig. 10 — Showing receiving antenna at Cupar 



Having followed the radio transmission as the waves radiate into 

 space and traverse space to the receiving end, we come to the matter 

 of receiving stations. Fig. 10 shows a view of the wave antenna at 

 Cupar, Scotland, used for receiving long waves. This complete 

 antenna arrangement is made up of two pole lines such as shown, each 

 about 3 miles long; a third may be added. These pole lines are placed 

 parallel to each other with separations of about two miles. A pole 

 line joins the two together and connects them to the receiving stations. 



It is fortunate that in America (and the same is true to a considerable 

 extent in England) the signals come in from a northerly direction and 

 the static tends to come in from almost the directly opposite direction. 

 The directivity brought about by such anlennre has, therefore, a very 

 large effect. It is estimated that under average conditions the present 



