Indicate the false statement. Noise figure is defined as A. the ratio of the S/N power supplied at the input terminal of a receiver or amplifier to the S/N power supplied to the output or load resistor B. noise factor expressed in decibels C. an unwanted form of energy tending to interfere with the proper and easy reception and reproduction of wanted signal D. S/N of an ideal system divided by S/N at the output of the receiver or amplifier under test, both working at the same temperature over the same bandwidth and fed from the same source

Indicate the false statement. Noise figure is defined as
A. the ratio of the S/N power supplied at the input terminal of a receiver or amplifier to
the S/N power supplied to the output or load resistor
B. noise factor expressed in decibels
C. an unwanted form of energy tending to interfere with the proper and easy
reception and reproduction of wanted signals
D. S/N of an ideal system divided by S/N at the output of the receiver or amplifier under
test, both working at the same temperature over the same bandwidth and fed from the
same source
by

1 Answer

Answer :

C. an unwanted form of energy tending to interfere with the proper and easy
reception and reproduction of wanted signals
by

Related questions

Calculate the noise figure of the receiver whose RF amplifier has an input resistance of 1000Ω and an equivalent shot-noise resistance of 2000Ω, a gain of 25 and load resistance of 125 kΩ. Given that the bandwidth is 1.0MHz and the temperature is 20˚C, and that the receiver is connected to an antenna with an impedance of 75Ω. A. 30.3 B. 3.03 C. 303 D. .303

Description : Calculate the noise figure of the receiver whose RF amplifier has an input resistance of 1000Ω and an equivalent shot-noise resistance of 2000Ω, a gain of 25 and load resistance of 125 kΩ. Given that the bandwidth is 1. ... to an antenna with an impedance of 75Ω. A. 30.3 B. 3.03 C. 303 D. .303

Last Answer : A. 30.3

Indicate the false statement A. The noise generated in a resistance or the resistive component of any impedance is random. B. Random noise power is proportional to the bandwidth over which is measured C. A random voltage across the resistor does not exist D. All formula referring to random noise are applicable only to the value of such noise.

Description : Indicate the false statement A. The noise generated in a resistance or the resistive component of any impedance is random. B. Random noise power is proportional to the bandwidth over which is measured ... exist D. All formula referring to random noise are applicable only to the value of such noise.

Last Answer : C. A random voltage across the resistor does not exist

What bandwidth is needed to support a capacity of 128 kbps when the signal power to noise power ratio in decibels is 100? A. 19224 Hz B. 3853 Hz C. 19244 Hz D. 3583 Hz

Description : What bandwidth is needed to support a capacity of 128 kbps when the signal power to noise power ratio in decibels is 100? A. 19224 Hz B. 3853 Hz C. 19244 Hz D. 3583 Hz

Last Answer : B. 3853 Hz

The noise output of a resistor is amplified by a noiseless amplifier having a gain of 60 and a bandwidth of 20 kHz. A meter connected at the output of the amplifier reads 1mV RMS. If the bandwidth of the amplifier is reduced to 5kHz, its gain remaining constant, what does the meter read now? A. 0.5 mV B. 0.5 µV C. 5.0 mV D. 5.0 µV

Description : The noise output of a resistor is amplified by a noiseless amplifier having a gain of 60 and a bandwidth of 20 kHz. A meter connected at the output of the amplifier reads 1mV RMS. If the bandwidth of the amplifier is reduced to ... does the meter read now? A. 0.5 mV B. 0.5 µV C. 5.0 mV D. 5.0 µV

Last Answer : A. 0.5 mV

The first stage of a two-stage amplifier has a voltage gain of 10, a 600 Ω input resistor, a 1600Ω equivalent noise resistance and 27kΩ output resistor. For the second stage, these values are 25, 81kΩ, 19kΩ, and 1MΩ, respectively. Calculate the equivalent input-noise resistance of this two stage amplifier. A. 2,518 kΩ B. 2,518 Ω C. 251.8 Ω D. 12,518 Ω

Description : The first stage of a two-stage amplifier has a voltage gain of 10, a 600 Ω input resistor, a 1600Ω equivalent noise resistance and 27kΩ output resistor. For the second stage, these values are 25, 81kΩ, 19kΩ, and 1MΩ, ... this two stage amplifier. A. 2,518 kΩ B. 2,518 Ω C. 251.8 Ω D. 12,518 Ω

Last Answer : B. 2,518 Ω

An amplifier operating over the frequency range of 455 to 460 kHz has a 200 kΩ input resistor. What is the RMS noise voltage at the input to this amplifier if the ambient temperature is 17˚C ? A. 40 µV B. 4.0 µV C. 400 µV

Description : An amplifier operating over the frequency range of 455 to 460 kHz has a 200 kΩ input resistor. What is the RMS noise voltage at the input to this amplifier if the ambient temperature is 17˚C ? A. 40 µV B. 4.0 µV C. 400 µV

Last Answer : B. 4.0 µV

The ratio of the level of the modulated output of a transmitter under conditions of standard test modulation to the level of the demodulated output with no modulation applied both measured with the same bandwidth. A. Reference audio output B. None of these C. Audio frequency response D. Residual noise level

Description : The ratio of the level of the modulated output of a transmitter under conditions of standard test modulation to the level of the demodulated output with no modulation applied both measured with the ... . Reference audio output B. None of these C. Audio frequency response D. Residual noise level

Last Answer : D. Residual noise level

Indicate the false statement. A. HF mixer are generally noisier than HF amplifiers. B. Impulse noise voltage is dependent on bandwidth C. Thermal noise is independent of the frequency at which is measured. D. Industrial noise is usually of the impulse type.

Description : Indicate the false statement. A. HF mixer are generally noisier than HF amplifiers. B. Impulse noise voltage is dependent on bandwidth C. Thermal noise is independent of the frequency at which is measured. D. Industrial noise is usually of the impulse type.

Last Answer : B. Impulse noise voltage is dependent on bandwidth

The square of the thermal noise voltage generated by a resistor is proportional to A. its resistance B. its temperature C. the bandwidth over which it is measured D. All of the above

Description : The square of the thermal noise voltage generated by a resistor is proportional to A. its resistance B. its temperature C. the bandwidth over which it is measured D. All of the above

Last Answer : D. All of the above

In the illustration, the component VR2 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to terminal 1 that controls the input to terminal 10 C. a zener diode that regulates the voltage to terminal 2 at 9.1 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Description : In the illustration, the component VR2 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to terminal ... 2 at 9.1 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Last Answer : Answer: C

In the illustration, the component VR1 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to terminal 9 that controls the input to terminal 10 C. a zener diode that regulates the voltage to terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Description : In the illustration, the component VR1 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to ... terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Last Answer : Answer: A

What signal-to-noise ratio is required for satisfactory television reception? A. 10 dB B. 30 dB C. 40 dB D. 20 dB

Description : What signal-to-noise ratio is required for satisfactory television reception? A. 10 dB B. 30 dB C. 40 dB D. 20 dB

Last Answer : C. 40 dB

The signal to noise ratio that is required for a satisfactory television reception. A. 30 dB B. 40 dB C. 10 dB D. 20 dB

Description : The signal to noise ratio that is required for a satisfactory television reception. A. 30 dB B. 40 dB C. 10 dB D. 20 dB

Last Answer : B. 40 dB

At 17˚ C, the noise voltage generated by 5kΩ resistor, operating over a bandwidth of 20KHz is A. 1.3 nV B. 1.3 µV C. 1.3 pV D. 1.3 mV

Description : At 17˚ C, the noise voltage generated by 5kΩ resistor, operating over a bandwidth of 20KHz is A. 1.3 nV B. 1.3 µV C. 1.3 pV D. 1.3 mV

Last Answer : B. 1.3 µV

Indicate the false statement. A. Industrial noise is usually of the impulse type B. Static is caused by lightning discharges in thunderstorms and other natural electric disturbances occurring in the atmosphere C. Distant stars are another source of man-made noise D. Flourescent lights are another source of man-made noise

Description : Indicate the false statement. A. Industrial noise is usually of the impulse type B. Static is caused by lightning discharges in thunderstorms and other natural electric disturbances occurring in the ... another source of man-made noise D. Flourescent lights are another source of man-made noise

Last Answer : C. Distant stars are another source of man-made noise

What establishes the receiver bandwidth? A. RF amplifier B. Mixer C. Local oscillator D. IF amplifier

Description : What establishes the receiver bandwidth? A. RF amplifier B. Mixer C. Local oscillator D. IF amplifier

Last Answer : D. IF amplifier

A dipole antenna requires to be fed with 20 kW of power to produce a given signal strength to a particular distant point. If the addition of a reflector makes the same field strength available with an input power of 11kW. What is the gain in dB, obtained by the use if the reflector. (Gain referred to this particular dipole). A. 4.75 B. 2.6 C. 1.81 D. 4.24

Description : A dipole antenna requires to be fed with 20 kW of power to produce a given signal strength to a particular distant point. If the addition of a reflector makes the same field strength available with an input power of 11kW ... Gain referred to this particular dipole). A. 4.75 B. 2.6 C. 1.81 D. 4.24

Last Answer : B. 2.6

Calculated the noise figure of the amplifier whose Req equals 2518Ω (RT=600Ω) if its driven by a generator whose output impedance is 50Ω. A. 39.4 B. 3.94 C. 394 D. 0.394

Description : Calculated the noise figure of the amplifier whose Req equals 2518Ω (RT=600Ω) if its driven by a generator whose output impedance is 50Ω. A. 39.4 B. 3.94 C. 394 D. 0.394

Last Answer : A. 39.4

Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150MHz) marine-band receiver? A. Man-made noise B. In the atmosphere C. In the receiver front end D. In the ionosphere

Description : Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150MHz) marine-band receiver? A. Man-made noise B. In the atmosphere C. In the receiver front end D. In the ionosphere

Last Answer : C. In the receiver front end

Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150 MHz) marine-band receiver? A. In the ionosphere B. In the receiver rear end C. In the receiver front end D. In the atmosphere

Description : Where is the noise generated that primarily determines the signal-to-noise ratio in a VHF (150 MHz) marine-band receiver? A. In the ionosphere B. In the receiver rear end C. In the receiver front end D. In the atmosphere

Last Answer : C. In the receiver front end

What is the reliable measurement for comparing amplifier noise characteristics? A. Thermal agitation noise B. Noise factor C. Noise margin D. Signal-to-noise

Description : What is the reliable measurement for comparing amplifier noise characteristics? A. Thermal agitation noise B. Noise factor C. Noise margin D. Signal-to-noise

Last Answer : B. Noise factor

What is the noise voltage across a 300Ω input resistance to a TV set with a 6MHz bandwidth and temperature of 30˚C? A. 2.3 µV B. 3.8µV C. 5.5µV D. 5.4µV

Description : What is the noise voltage across a 300Ω input resistance to a TV set with a 6MHz bandwidth and temperature of 30˚C? A. 2.3 µV B. 3.8µV C. 5.5µV D. 5.4µV

Last Answer : C. 5.5µV

What satellite system parameter represents the quality of a satellite or an earth station receiver? A. Gain-to-Equivalent Noise Temperature Ratio (G/Te) B. Energy of Bit-to-Noise Density Ratio (Eb/No) C. Carrier-to-Noise Density Ratio (C/No) D. Bit energy

Description : What satellite system parameter represents the quality of a satellite or an earth station receiver? A. Gain-to-Equivalent Noise Temperature Ratio (G/Te) B. Energy of Bit-to-Noise Density Ratio (Eb/No) C. Carrier-to-Noise Density Ratio (C/No) D. Bit energy

Last Answer : A. Gain-to-Equivalent Noise Temperature Ratio (G/Te)

ECE Board Exam March 1996 What is the purpose of a beat frequency oscillator (BFO)? A. Aid in the reception of weak voice-modulated signals B. Generates a signal, whose frequency is the same as that of the intermediate frequency C. Generates a 1kHz note for Morse code reception D. Generates an output, whose frequency differs from that of the intermediate frequency by 1 kHz

Description : ECE Board Exam March 1996 What is the purpose of a beat frequency oscillator (BFO)? A. Aid in the reception of weak voice-modulated signals B. Generates a signal, whose frequency is the ... reception D. Generates an output, whose frequency differs from that of the intermediate frequency by 1 kHz

Last Answer : C. Generates a 1kHz note for Morse code reception

Unwanted radio signal on assigned frequency. A. Splatter B. RFI C. Noise D. EMI

Description : Unwanted radio signal on assigned frequency. A. Splatter B. RFI C. Noise D. EMI

Last Answer : C. Noise

What is meant by antenna gain? A. The final amplifier gain minus the transmission line losses (including any phasing lines present) B. The ratio of the amount of power produced by the antenna compared to the output power of the transmitter C. The ratio of the signal in the backward direction D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna

Description : What is meant by antenna gain? A. The final amplifier gain minus the transmission line losses (including any phasing lines present) B. The ratio of the amount of power produced by the antenna ... D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna

Last Answer : D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna

A receiver connected to an antenna whose resistance is 50 Ω has an equivalent noise resistance of 30Ω. Calculate its equivalent noise temperature if the noise figure is equal to 1.6. A. 17.4 K B. 174K C. 1.74K D. 17K

Description : A receiver connected to an antenna whose resistance is 50 Ω has an equivalent noise resistance of 30Ω. Calculate its equivalent noise temperature if the noise figure is equal to 1.6. A. 17.4 K B. 174K C. 1.74K D. 17K

Last Answer : B. 174K

The total noise power present in a 1-Hz bandwidth . A. Noise density B. Noise figure C. Noise limit D. Noise intensity

Description : The total noise power present in a 1-Hz bandwidth . A. Noise density B. Noise figure C. Noise limit D. Noise intensity

Last Answer : A. Noise density

Which circuit contributes most of the noise in a receiver? A. IF amplifier B. Demodulator C. AF amplifier D. Mixer

Description : Which circuit contributes most of the noise in a receiver? A. IF amplifier B. Demodulator C. AF amplifier D. Mixer

Last Answer : D. Mixer

Referred to as the stage in the radio receiver that contributes most of the noise. A. IF amplifier B. Supply stage C. Speaker D. Mixer

Description : Referred to as the stage in the radio receiver that contributes most of the noise. A. IF amplifier B. Supply stage C. Speaker D. Mixer

Last Answer : D. Mixer

What do you call the single booster installed on the antenna dish of satellite receiver? A. Low noise amplifier B. Single amplifier C. Noise amplifier D. Rectifier

Description : What do you call the single booster installed on the antenna dish of satellite receiver? A. Low noise amplifier B. Single amplifier C. Noise amplifier D. Rectifier

Last Answer : A. Low noise amplifier

The difference between the original and reconstructed signal gives rise to A. S factor B. Quantizing noise C. S/N D. Fade margin

Description : The difference between the original and reconstructed signal gives rise to A. S factor B. Quantizing noise C. S/N D. Fade margin

Last Answer : B. Quantizing noise

ECE Board Exam March 1996 The equivalent noise temperature of the amplifier is 25 K. What is the noise figure? A. 1.86 B. 0.1086 C. 1.086 D. 10.86

Description : ECE Board Exam March 1996 The equivalent noise temperature of the amplifier is 25 K. What is the noise figure? A. 1.86 B. 0.1086 C. 1.086 D. 10.86

Last Answer : C. 1.086

What limits the sensitivity of a receiver? A. The power supply of the receiver B. The power output of a transmitter C. The noise floor of the receiver D. The distance between the transmitter and receiver

Description : What limits the sensitivity of a receiver? A. The power supply of the receiver B. The power output of a transmitter C. The noise floor of the receiver D. The distance between the transmitter and receiver

Last Answer : C. The noise floor of the receiver

Three identical circuits having 10 dB signal noise-to-noise ratio each are connected in tandem with each other, what is the overall S/N? A. 5.23 dB B. 14.77dB C. 30 dB D. 40 dB

Description : Three identical circuits having 10 dB signal noise-to-noise ratio each are connected in tandem with each other, what is the overall S/N? A. 5.23 dB B. 14.77dB C. 30 dB D. 40 dB

Last Answer : A. 5.23 dB

Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave? A. AF amplifier B. Antenna C. Detector D. Crystal

Description : Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave? A. AF amplifier B. Antenna C. Detector D. Crystal

Last Answer : B. Antenna

A one-quarter wavelength shunt-fed vertical Marconi antenna A. has maximum radiation in a vertical direction B. must have a horizontal receiving antenna for the best reception C. must use a receiving antenna for the best reception D. must have a vertical receiving antenna for the best reception

Description : A one-quarter wavelength shunt-fed vertical Marconi antenna A. has maximum radiation in a vertical direction B. must have a horizontal receiving antenna for the best reception C. must use a receiving antenna for the best reception D. must have a vertical receiving antenna for the best reception

Last Answer : D. must have a vertical receiving antenna for the best reception

Noise at the input to the receiver can be as high as several A. microvolts B. milivolts C. volts D. kilo volts

Description : Noise at the input to the receiver can be as high as several A. microvolts B. milivolts C. volts D. kilo volts

Last Answer : A. microvolts

Deemphasis in the receiver in effect attenuates modulating signal components and noise in what frequency range? A. dc B. low C. intermediate D. high

Description : Deemphasis in the receiver in effect attenuates modulating signal components and noise in what frequency range? A. dc B. low C. intermediate D. high

Last Answer : D. high

When no signal is being received, the loudspeaker is not entirely silent as a result of the presence of A. parasitic oscillations in some of the receiver stages. B. negative feedback in each stage. C. spurious frequencies as a result of improper neutralization. D. internal receiver noise.

Description : When no signal is being received, the loudspeaker is not entirely silent as a result of the presence of A. parasitic oscillations in some of the receiver stages. B. negative feedback in each stage. C. spurious frequencies as a result of improper neutralization. D. internal receiver noise.

Last Answer : D. internal receiver noise.

ECE Board Exam March 1996 What is the purpose of the receiver’s squelch circuit? A. To overcome fluctuations in the level the RF signal arriving at the receiver antenna B. To prevent fluctuations in the AGC bias level C. To reduce the receiver’s sensitivity to all incoming signals D. To prevent amplified noise from reaching the loudspeaker during the absence of an incoming signal

Description : ECE Board Exam March 1996 What is the purpose of the receiver's squelch circuit? A. To overcome fluctuations in the level the RF signal arriving at the receiver antenna B. To prevent ... signals D. To prevent amplified noise from reaching the loudspeaker during the absence of an incoming signal

Last Answer : D. To prevent amplified noise from reaching the loudspeaker during the absence of an incoming signal

Which noise figure represents the lowest noise in receiver? A. 1.6 dB B. 2.1 dB C. 2.7 dB D. 3.4 dB

Description : Which noise figure represents the lowest noise in receiver? A. 1.6 dB B. 2.1 dB C. 2.7 dB D. 3.4 dB

Last Answer : A. 1.6 dB

In the illustration, the component VR1 on the A1A1 PCB is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply B. a variable resistor diode to control the output to terminal 9 that controls the input to terminal 10 C. a zener diode that regulates the voltage to terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Description : In the illustration, the component VR1 on the A1A1 PCB is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply B. a variable resistor diode to control the output to terminal 9 that controls ... terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Last Answer : Answer: C

What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path? A. Quadruple B. Frequency C. Polarization D. Space

Description : What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path? A. Quadruple B. Frequency C. Polarization D. Space

Last Answer : B. Frequency

One of the following is not a useful quantity for comparing the noise performance receivers. A. Input noise voltage B. Equivalent noise resistance C. Noise temperature D. Noise figure.

Description : One of the following is not a useful quantity for comparing the noise performance receivers. A. Input noise voltage B. Equivalent noise resistance C. Noise temperature D. Noise figure.

Last Answer : A. Input noise voltage

In the illustrated circuit, what is the phase relationship of the amplifier output compared to the input? EL-0022 A. 0° in-phase B. 180° out of phase C. phase angle of the input divided by power factor D. unable to determine without the value of the bias voltage

Description : In the illustrated circuit, what is the phase relationship of the amplifier output compared to the input? EL-0022 A. 0° in-phase B. 180° out of phase C. phase angle of the input divided by power factor D. unable to determine without the value of the bias voltage

Last Answer : Answer: B

The total propagation delay time from transmission to reception of signals from a ground transmitter to ground receiver with angle of elevation at 10 degrees respectively is A. 273 ms B. 239 ms C. 275 ms D. 260 ms

Description : The total propagation delay time from transmission to reception of signals from a ground transmitter to ground receiver with angle of elevation at 10 degrees respectively is A. 273 ms B. 239 ms C. 275 ms D. 260 ms

Last Answer : A. 273 ms

What is the purpose of having input and output capacitors in three terminal IC regulators?

Description : What is the purpose of having input and output capacitors in three terminal IC regulators?

Last Answer : A capacitor connected between the input terminal and ground cancels the inductive effects due to long distribution leads. The output capacitor improves the transient response.

Noise can be reduced by A. widening the bandwidth B. narrowing the bandwidth C. increasing temperature D. increasing transistor current levels

Description : Noise can be reduced by A. widening the bandwidth B. narrowing the bandwidth C. increasing temperature D. increasing transistor current levels

Last Answer : B. narrowing the bandwidth