8-11B: Transmitting Systems

Question 1

8-11B1

The magnetron is used to:
A. Generate the output signal at the proper operating frequency
B. Determine the shape and width of the transmitted pulses
C. Modulate the pulse signal.
D. Determine the pulse repetition rate.

Answer 1

ANSWER A
The magnetron is a thermionic vacuum tube with a large permanent magnet surrounding the tube and is found in the power output stage of a RADAR. Whe properly assembled, the magnetron will generate a stable output signal at the proper operating frequency.

Question 2

8-11B3

Which of the following statements about most modern RADAR
transmitter power supplies is false?

A. High voltage supplies may produce voltages in excess of 5,000 volts AC.
B. There are usually separate low voltage and high voltage supplies.
C. Low voltage supplies use switching circuits to deliver multiple voltages.
D. Low voltage supplies may supply both AC and DC voltages.

Answer 2

ANSWER A
Here they ask which statement is FALSE. Most RADARs may feed the modulator with a high-voltage, DC (NOT AC) pwer supply, using half wave, full wave, or bridge rectification. These power supplies MUST be cooled by an airflow system.

Question 3

8-11B6

Which of the following is not part of the transmitting system?

A. Magnetron.
B. Modulator.
C. Pulse Forming Network.
D. Klystron.

Answer 3

ANSWER D
The klystron may be found in the RADAR receiver local oscillator, using 30 MHz or 60 MHz intermediate frequency.