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Flashcards in Element 8 Photo Deck (20)
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1

8-7A1  What component of a RADAR receiver is represented by block 46 in Fig. 8A1?

        A.    The ATR box.

        B.    The TR box.

        C.    The RF Attenuator.

        D.    The Crystal Detector.

B.    The TR box.

 

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2

8-7A6  What component of a RADAR receiver is represented by block 47 in Fig. 8A1?

        A.    The ATR box.

        B.    The TR box.

        C.    The RF Attenuator.

        D.    The Crystal Detector.

C.    The RF Attenuator.

 

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3

8-9A2   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 is used for address decoding.

        B.    The Memory and I/O communicate with peripherals.

        C.    The control unit executes arithmetic manipulations.

        D.    The internal bus is used simultaneously by all units.

B.    The Memory and I/O communicate with peripherals.

 

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4

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.

A.    The ALU executes arithmetic manipulations.

 

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5

8-9A5  In the Line-Driver/Coax/Line-receiver circuit shown in Fig. 8A3, what component is represented by the blank box marked "X"?

        A.    25-ohm resistor.

        B.    51-ohm resistor.

        C.    10-microhm inductor.

        D.    20-microhm inductor.

B.    51-ohm resistor.

 

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6

8-10A1  In the circuit shown in Fig. 8A4, U5 pins 1 and 4 are high and both are in the reset state.  Assume one clock cycle occurs of Clk A followed by one cycle of Clk B. What are the output states of the two D-type flip flops?

        A.    Pin 5 low, Pin 9 low.

        B.    Pin 5 high, Pin 9 low.

        C.    Pin 5 low, Pin 9 high.

        D.    Pin 5 high, Pin 9 high.

D.    Pin 5 high, Pin 9 high.

 

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7

8-10A2  If more light strikes the photodiode in Fig. 8A5, there will be:

        A.    Less diode current.

        B.    No change in diode current.

        C.    More diode current.

        D.    There is wrong polarity on the diode.

C.    More diode current.

 

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8

8-10A3  In the circuit shown in Fig. 8A6, which of the following is true?

        A.    With A and B high, Q1 is saturated and Q2 is off.

        B.    With either A or B low, Q1 is saturated and Q2 is off.

        C.    With A and B low, Q2 is on and Q4  is off.

        D.    With either A or B low, Q1 is off and Q2 is on.

B.    With either A or B low, Q1 is saturated and Q2 is off.

 

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9

8-10A4  What is the correct value of RS in Fig. 8A7, if the voltage across the LED is 1.9 Volts with 5 Volts applied and If max equals 40 milliamps?

        A.    4,700 ohms.

        B.    155 ohms.

        C.    77 ohms.

        D.    10,000 ohms.

C.    77 ohms.

 

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10

8-10A5  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 is used for address decoding.

        B.    General registers are used for arithmetic manipulations.

        C.    The control unit executes arithmetic manipulations.

        D.    Address pointers are contained in the general registers.

D.    Address pointers are contained in the general registers.

 

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11

8-10A6  You are troubleshooting a component on a printed circuit board in a RADAR system while referencing the Truth Table in Fig. 8A8. What kind of integrated circuit is the component?

        A.    D-type Flip-Flop, 3-State, Inverting.

        B.    Q-type Flip-Flop, Non-Inverting.

        C.    Q-type Directional Shift Register, Dual.

        D.    D to Q Convertor, 2-State.

A.    D-type Flip-Flop, 3-State, Inverting.

 

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12

8-20C1  The diagram in Fig. 8C9 shows a simplified RADAR mixer circuit using a crystal diode as the first detector. What is the output of the circuit when no echoes are being received?

        A.    60 MHz CW.

        B.    4095 MHz CW.

        C.    4155 MHz CW.

        D.    No output is developed. 

D.    No output is developed.

 

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13

8-20C5  What component of a RADAR receiver is represented by block 49 in Fig. 8A1?

        A.    Discriminator.

        B.    IF amplifier.

        C.    Klystron.

        D.    Crystal detector (the mixer).

D.    Crystal detector (the mixer).

 

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14

8-21C3  What component of a RADAR receiver is represented by block 48 in Fig. 8A1?

        A.    Klystron (local oscillator).

        B.    Discriminator.

        C.    IF amplifier.

        D.    Crystal detector.

A.    Klystron (local oscillator).

 

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15

8-24C6  What component is block 50 in Fig. 8A1?

        A.    IF amplifier.

        B.    AFC amplifier.

        C.    Discriminator.

        D.    Crystal detector.

C.    Discriminator.

 

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16

8-26C3  The circuit shown in Fig. 8C10 is the output of a switching power supply. Measuring from the junction of CR6, CR7 and L1 to ground with an oscilloscope, what waveform would you expect to see?

        A.    Filtered DC.

        B.    Pulsating DC at line frequency.

        C.    AC at line frequency.

        D.    Pulsating DC much higher than line frequency.

D.    Pulsating DC much higher than line frequency.

 

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17

8-26C4  With regard to the comparator shown in Fig. 8C11, the input is a sinusoid. Nominal high level output of the comparator is 4.5 volts. Choose the most correct statement regarding the input and output.

        A.    The leading edge of the output waveform occurs 180 degrees after positive zero crossing of the input waveform.

        B.    The rising edge of the output waveform trails the positive zero crossing of the input waveform by 45 degrees.

        C.    The rising edge of the output waveform trails the negative zero crossing of the input waveform by 45 degrees.

        D.    The rising edge of the output waveform trails the positive peak of the input waveform by 45 degrees.

A.    The leading edge of the output waveform occurs 180 degrees after positive zero crossing of the input waveform.

 

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18

8-26C6  The nominal output high of the comparator shown in Fig. 8C11 is 4.5 volts. Choose the most correct statement which describes the trip points.

        A.    Upper trip point is 4.5 volts. Lower trip point is approximately 0 volts.

        B.    Upper trip point is 2.5 volts. Lower trip point is approximately 2.0 volts.

        C.    Upper trip point is 900 microvolts. Lower trip point is approximately 0 volts.

        D.    Upper trip point is +1.285 volts. Lower trip point is -1.285 volts.

D.    Upper trip point is +1.285 volts. Lower trip point is -1.285 volts.

 

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19

8-45F1  A circuit card in a RADAR system has just been replaced with a spare card. You notice the voltage level at point E in Fig. 8F12 is negative 4.75 volts when the inputs are all at 5 volts. The problem is:

        A.    The 25 K resistor is open.

        B.    The 100 K resistor has been mistakenly replaced with a 50 K resistor.

        C.    The op amp is at the rail voltage.

        D.    The 50 K resistor has been mistakenly replaced with a 25 K resistor.

D.    The 50 K resistor has been mistakenly replaced with a 25 K resistor.

 

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20

8-45F4  In the circuit contained in Fig. 8F12, there are 5 volts present at points B and C, and there are zero volts present at points A and D. What is the voltage at point E?

        A.    -1.5 Volts.

        B.    3.75 Volts.

        C.    23.75 Volts.

        D.    4.5 Volts.

A.    -1.5 Volts.

 

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