36 



OCEAN ELECTRONIC NAVIGATIONAL AIDS 



I'iGUKE 3-2. — Views of Kadar reflector-equipped buoys. 



tially a continuously pulsing microwave transmitter at some known location. 

 It may be picked up by any navigational Radar whose receiver is capable of 

 being retuned slightly to the established beacon frequency, as the Ramark 

 frequency differs slightly from that of the normal search frequency. When 

 the navigator's Radar receiver is so tuned, the Ramark appears as a con- 

 tinuous azimuth line on the Radar scope, while reflections from objects are 

 obliterated from it. (See fig. 3-4.) Also, this beacon may be utilized by 

 vessels having only a microwave receiver and directional antenna. 



At the recent ITU conference in Atlantic City, Radar beacon frequencies 

 of 3256 megacycles (S-band) and 9310 megacycles (X-band) were allo- 

 cated. These frequencies differ from the normal search frequencies in these 



