单项选择题
A.persistence
B.pulse repetition rate
C.pulse length
D.rotation rate
单项选择题 The number of pulses of energy transmitted per second is call the（）.
单项选择题 The radar component that generates the radio-frequency energy in the form of short powerful pulses is which of the following?（）.
单项选择题 The radar component that produces the synchronizing signal and triggers the indicator sweep is which of the following?（）.