Key Topic 44: Equipment Faults-1

Question 1

8-44F1: When you examine the RADAR you notice that there is no target video in the center of the CRT. The blank spot gets smaller in diameter as you increase the range scale. What operator front panel control could be misadjusted?

A. TUNE.
B. Sensitivity Time Control (STC).
C. Anti-Clutter Rain (ACR).
D. False Target Elimination (FTE).

Answer 1

B. Sensitivity Time Control (STC).

Question 2

8-44F2: Range rings on the PPI indicator are oval in shape. Which circuit would you suspect is faulty?

A. Timing circuit.
B. Video amplifier circuit.
C. Range marker circuit.
D. Sweep generation circuit.

Answer 2

D. Sweep generation circuit.

Question 3

8-44F3: What would be the most likely defective area when there is no target video in the center of the CRT and the blank spot gets smaller in diameter as your range scale is increased?

A. The TR (TRL) Cell.
B. The local oscillator is misadjusted.
C. Video amplifier circuit.
D. The IF amplifier circuit.

Answer 3

A. The TR (TRL) Cell.

Question 4

8-44F4: While the vessel is docked the presentation of the pier is distorted near the center of the PPI with the pier appearing to bend in a concave fashion. This is a primary indication of what?

A. The deflection coils need adjusting.
B. The centering magnets at the CRT neck need adjusting.
C. The waveguide compensation delay line needs adjusting.
D. The CRT filaments are weakening.

Answer 4

C. The waveguide compensation delay line needs adjusting.

Question 5

8-44F5: In a RADAR using digital video processing, a bright, wide ring appears at a fixed distance from the center of the display on all digital ranges. The transmitter is operating normally. What receiver circuit would you suspect is causing the problem?

A. VRM circuit.
B. Video storage RAM or shift register.
C. Range ring generator.
D. EBL circuit.

Answer 5

B. Video storage RAM or shift register.

Question 6

8-44F6: The raster scan RADAR display has missing video in a rectangular block on the screen. Where is the most likely problem area?

A. Horizontal sweep circuit.
B. Power supply.
C. Memory area failure.
D. Vertical blanking pulse.

Answer 6

C. Memory area failure.