Key Topic 38: Miscellaneous

Question 1

8-38D1: The heading flash is a momentary intensification of the sweep line on the PPI presentation. Its function is to:

A. Alert the operator when a target is within range.
B. Alert the operator when shallow water is near.
C. Inform the operator of the dead-ahead position on the PPI scope.
D. Inform the operator when the antenna is pointed to the rear of the ship.

Answer 1

C. Inform the operator of the dead-ahead position on the PPI scope.

Question 2

8-38D2: The major advantage of digitally processing a RADAR signal is:

A. Digital readouts appear on the RADAR display.
B. Enhancement of weak target returns.
C. An improved operator interface.
D. Rectangular display geometry is far easier to read on the CRT.

Answer 2

B. Enhancement of weak target returns.

Question 3

8-38D3: In order to ensure that a practical filter is able to remove undesired components from the output of an analog-to-digital converter, the sampling frequency should be:

A. The same as the lowest component of the analog frequency.
B. Two times the highest component of the analog frequency.
C. Greater than two times the highest component of the sampled frequency.
D. The same as the highest component of the sampled frequency.

Answer 3

C. Greater than two times the highest component of the sampled frequency.

Question 4

8-38D4: Bearing resolution is:

A. The ability to distinguish two adjacent targets of equal distance.
B. The ability to distinguish two targets of different distances.
C. The ability to distinguish two targets of different elevations.
D. The ability to distinguish two targets of different size.

Answer 4

A. The ability to distinguish two adjacent targets of equal distance.

Question 5

8-38D5: The output of an RC integrator, when driven by a square wave with a period of much less than one time constant is a:

A. Sawtooth wave.
B. Sine wave.
C. Series of narrow spikes.
D. Triangle wave.

Answer 5

D. Triangle wave.

Question 6

8-38D6: How do you eliminate stationary objects such as trees, buildings, bridges, etc., from the PPI presentation?

A. Remove the discriminator from the unit.
B. Use a discriminator as a second detector.
C. Calibrate the IF circuit.
D. Calibrate the local oscillator.

Answer 6

B. Use a discriminator as a second detector.