8-9A: Circuits 1 Flashcards
RADAR Principles (4 cards)
8-9A2
The block dlagram of a typical RADAR system microprocessor is shown in Fig. 8A2. Choose the most correcl statement regarding this system.
A. The ALU is used for address decoding.
B. The Memory and l/O communicate with peripherals.
C, The control unit executes arithmetic manipulations
D. The internal bus is used simultaneously by all units
ANSWER B
The two memory systems, along with the CPU (Central Processing Unit), provide the operating instructions to the RADAR system. The l/O (lnput/Output) device is primarily responsible for data transfers between the CPU and all other supporting circuits outside the CPU. lt can be seen from the diagram that the memory and l/O buss will receive lnput from GPS, LORAN, GYN and boat speed in a marine system.
8-9A3
The phantastron circuit is capable of:
A. Stabilizing the magnetron.
B. Preventing saturation of the RADAR receiver.
C. Being used to control repeller voltage in the AFC system.
D. Developing a linear ramp voltage when triggered by an external source.
ANSWER D
The phantastron circuit is a variable-length sawtooth generator which develops a linear ramp voltage when triggered by an external source. The phantastron is found in the sweep circuit, feeding a steep sawtooth to the sweep amplifier, dependent on the range selected by the RADAR operator.
8-9A4
The block diagram of a typical RADAR system microprocessor is shown in Fig. 8A2. Choose the most correct statement regarding this system.
A. The ALU executes arithmetic manipulations.
B. The ALU is used for address decoding.
C. General registers are used for arithmetic manipulations.
D. Address pointers are contained in the control unit.
ANSWER A
The ALU (Arithmetic Logic Unit) is the computer’s “brain” capable of adding and subtracting binary numbers that a microprocessor executes according to its program. The ALU can be tought of as the thinking part of a computer system.
8-9A6
Choose the most correct statement:
A. The magnetron anode is a low voltage circuit.
B. The anode of the magnetron carries high voltage.
C. The filament of the magnetron carries dangerous voltages.
D. The magnetron filament is a low voltage circuit.
ANSWER C
The filament is bombarded by electrons from the output of a magnetron, which travels in a loop. Plate voltage and field strength must be monitored to prevent destructive filament bombardment. The filament of the magnetron will carry a dangerous voltage.
