1-11.   A certain amount of time is required for a duplexer to disconnect the antenna from the receiver and connect it to the transmitter. What is this switching time called? 1.   Receiver recovery time 2.   Fast reaction time 3.   Detection time 4.   Transmitter recovery time 1-12.   What radar subsystem is used to convert RF echoes to a lower frequency? 1.   Superheterodyne receiver 2.   Antenna system 3.   Duplexer 4.   Transmitter 1-13.   Figure 1-5 shows four basic radar displays. Which of the displays uses your own ship as the center of the display? 1.   Type A 2.   Type B 3.   Type P 4.   Type E 1-14.   An automobile headlight is similar, in shape, to what type of radar reflector? 1.   Truncated 2.   Parabolic 3.   Orange peel 4.   Banana peel 1-15.   Radar antennas are designed using well- known optical design techniques.   Which of the following radar characteristics allows a radar antenna to be designed in this way? 1.   Radar operates in the microwave region of the electromagnetic spectrum 2.   Radar operates in the ultraviolet region of the electromagnetic spectrum 3.   Radar operates in the VLF region of the electromagnetic spectrum 4.   Radar operates in the infrared region of the electromagnetic spectrum 1-16.   What general characteristic of a horn radiator is determined by the size of its mouth opening? 1.   Symmetry 2.   Relativity 3.   Conductivity 4.   Directivity 1-17.   Which of the following design actions can be used to eliminate feedhorn shadows? 1.   Making the horn smaller 2.   Putting the horn behind the reflector 3.   Offsetting the horn from the center of the reflector 4.   Making the reflector smaller 1-18.   Which of the following antennas are lens type antennas? 1.   Conducting and dielectric 2.   Optical and electro-optical 3.   Flatplane and spherical plane 4.   Microwave and plane wave 1-19.   In a delay lens, the amount of delay is dependent on what characteristic? 1.   Thickness 2.   Dielectric constant 3.   Angle of reflection 4.   Angle of incidence 1-20.   Which of the following elements can be used in an array antenna? 1.   Slots 2.   Dipoles 3.   Horns 4.   Each of the above 1-21.   In an array antenna, what determines the position of the beam? 1.   The relative phase between the elements 2.   The relative amplitude between the elements 3.   The total amplitude of the elements 4.   The scan motor 1-22.   Which of the following adverse effects in a small radome is caused by reflected power? 1.   Beam deflection 2.   Transmission loss 3.   Antenna mismatch 4.   Secondary effects 1-23.   What level of maintenance do FC’s normally perform on radomes? 1.   Ship’s 2M 2.   Factory repairs 3.   Technical repairs 4.   Preventive maintenance 2