Description : Which amplifier stage (the preamplifier or the postamplifier) is a dominant contributor of noise and significantly influences the sensitivity of the receiver?
Last Answer : The preamplifier.
Description : List the key operational parameters used to define receiver performance.
Last Answer : Receiver sensitivity, bandwidth, and dynamic range.
Description : What is the main factor that determines receiver sensitivity?
Last Answer : Noise
Description : Fiber optic connectors can reduce system performance by increasing what two types of noise?
Last Answer : Modal and reflection.
Description : What are two types of noise that manifest themselves as shot noise?
Last Answer : Dark current and quantum noises.
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
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
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
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
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
Description : 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 ... under test, both working at the same temperature over the same bandwidth and fed from the same source
Last Answer : C. an unwanted form of energy tending to interfere with the proper and easy reception and reproduction of wanted signals
Description : The front-end of a television receiver, having a bandwidth of 7Mhz, and operating at a temperature of 27˚C , consists of an amplifier having a gain of 15 followed by a mixer whose gain is 20. The ... equivalent noise resistance for this television receiver. A. 8760 Ω B. 875Ω C. 8.76Ω D. 0.876Ω
Last Answer : B. 875Ω
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
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
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
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)
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.
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
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
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
Description : What is the mixing process? A. Distortion caused by auroral propagation B. The combination of two signals to produce sum and difference frequencies. C. The elimination of noise in wideband receiver by phase differentiation D. The elimination of noise in a wideband receiver by phase comparison
Last Answer : B. The combination of two signals to produce sum and difference frequencies.
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
Description : ECE Board Exam March 1996 A receiver connected to an antenna whose resistance is 50 ohms has an equivalent noise resistance of 30 ohms. What is the receiver’s noise temperature? A. 754 K B. 464 K C. 174 K D. 293 K
Last Answer : C. 174 K
Description : During the decoding process, the A)intensity of the transmission becomes stronger. B)receiver attempts to convert signs into concepts and ideas. C)source attempts to convert signs into concepts and ideas. D)receiver filters noise from the feedback.
Last Answer : B)receiver attempts to convert signs into concepts and ideas.
Description : What is the disadvantage of using a double receiver instead of two individual receivers?
Last Answer : If one of the receivers goes bad the entire unit must be replaced.
Description : When is a synchro receiver (TR) properly zeroed?
Last Answer : A TR is zeroed when electrical zero voltages exist across its stator windings at the same time its rotor is on zero or on its mechanical reference position.
Description : What is the most likely problem if the transmitter shaft reads 0º when the receiver shaft indicates 180º?
Last Answer : The rotor leads on either the transmitter or the receiver are reversed.
Description : What two receiver leads are reversed to reverse the rotor's direction of rotation?
Last Answer : 1 and S3.
Description : What is the relationship between the transmitter and receiver stator voltages when their rotors are in correspondence?
Last Answer : The voltages are equal and oppose each other.
Description : What is the physical difference between a synchro transmitter and a synchro receiver?
Last Answer : A synchro receiver uses some form of damping to retard excessive oscillations or spinning.
Description : Receiver bandwidth is defined as those frequencies spread between what two points of the receiver response curve?
Last Answer : Half-power points.
Description : When measuring receiver sensitivity, what quantities must you add to the dBm reading obtained on the signal generator or test set?
Last Answer : Attenuations of the directional coupler and the connecting cable.
Description : You determine receiver sensitivity by measuring the power level of what signal?
Last Answer : Minimum discernible signal (mds).
Description : A loss of receiver sensitivity has the same effect on range performance as what other loss?
Last Answer : Transmitter power loss.
Description : Where should the transmitter spectrum be located with respect to the receiver response curve?
Last Answer : In the center.
Description : A monopulse receiver has how many separate channels?
Last Answer : Three.
Description : How does ftc affect receiver gain, if at all?
Last Answer : FTC has no effect on receiver gain
Description : Immediately after the transmitter fires, stc reduces the receiver gain to what level?
Last Answer : Zero.
Description : Which receiver component converts the IF pulses to video pulses?
Last Answer : Detector.
Description : What receiver circuit actually produces the IF frequency?
Last Answer : Mixer.
Description : Which component of the receiver produces the signal that is mixed with the received signal to produce the IF signal?
Last Answer : Local oscillator.
Description : What type of receiver is most often used in radar systems?
Last Answer : Superheterodyne.
Description : What tube in a duplexer has the primary function of disconnecting the receiver?
Last Answer : Tr tube.
Description : what causes the initial and final pulses on the receiver output signal?
Last Answer : Leakage from the duplexer.
Description : What is the result of an impedance mismatch between a receiver or transmitter and its transmission line or antenna?
Last Answer : High vswr, which equates to poor reception or a loss of power output.
Description : Define receiver dynamic range.
Last Answer : The range of optical power levels over which the receiver operates within the specified values. It
Description : . Which part of the receiver amplifies the electrical signal to a level suitable for further signal processing?
Last Answer : Amplifier.
Description : What is a fiber optic receiver?
Last Answer : An electro-optic device that accepts optical signals from an optical fiber and converts them into electrical signals
Description : What is the function of a crystal filter in a receiver?
Last Answer : It is used to achieve maximum selectivity.
Description : What does a tone control circuit in a receiver do to the audio signal?
Last Answer : It controls the amount of bass and treble response.