Description : The analog signal needs to be sampled at a minimum sampling rate of: (A) 2fs (B) 1/(2fs) (C) fs/2 (D) 2/fs
Last Answer : (A) 2fs
Description : In a PCM system the number of quantization level are 16 and the maximum signal frequency is 4 KHz the transmission bit rate is
Last Answer : In a PCM system the number of quantization level are 16 and the maximum signal frequency is 4 KHz the transmission bit rate is 32 Kbits/sec
Description : As per Nyquist criterion the sampling rate is (A) 2fs (B) (1/2)fs (C) (1/2fs) (D) (2/fs) Where fs is the signal frequency
Description : Two resistors, 20kΩ, and 50kΩ are at ambient temperature. Calculate for a bandwidth equal to 100kHz, the thermal noise voltage for the two resistors connected in parallel. A. 0.4782µV B. 4278 µV C. 4.78 µV D. 47.8 µV
Last Answer : C. 4.78 µV
Description : State the need of signal conditioning and signal processing .List applications of instrumentation amplifier.
Last Answer : * In an instrumentation system, a transducer is used for sensing various parameters. The output of transducer is an electrical signal proportional to the physical quantity sensed such as pressure, ... monitoring and control 5) Light intensity meter 6) Measurement of flow and thermal conductivity
Description : Which of the following is an inherent property of an optical signal and cannot be eliminated even in principle? (1) Thermal noise (2) Shot noise (3) Environmental noise (4) Background Noise
Last Answer : Which of the following is an inherent property of an optical signal and cannot be eliminated even in principle? (1) Thermal noise (2) Shot noise (3) Environmental noise (4) Background Noise
Last Answer : In communication systems, the modulating signal is also called base band signal.
Description : Steps to follow to produce PCM signal. A. Quantizing, sampling, and coding B. Sampling, quantizing, and coding C. Sampling, coding and quantizing D. Coding, quantizing and coding
Last Answer : B. Sampling, quantizing, and coding
Description : Phenomena in which signal transmitted in one circuit creates undesired effect in other circuit is known as A. crosstalk B. signal attenuation C. sampling D. crosslinking
Last Answer : crosslinking
Description : The most common technique to change an analog signal to digitaldata is called __________. A) PAL B) PCM C) sampling D) none of the abov
Last Answer : PCM
Description : Choosing a discrete value that is near but not exactly at the analog signal level leads to a) PCM error b) Quantization error c) PAM error d) Sampling error
Last Answer : b) Quantization error
Description : The signals which are obtained by encoding each quantized signal into a digital word is called as a) PAM signal b) PCM signal c) FM signal d) Sampling and quantization
Last Answer : b) PCM signal
Description : Explain flat top sampling with circuit diagram.Draw flat top sampled signal.
Last Answer : Flat top sampling: In flat top sampling, the top of the samples remains constant and equal to the instantaneous value of the modulating signal at the start of the sampling. Thus the ... the sampled signal and the pulse signal. Flat top sampling is mostly used in digital transmission
Description : The analog signal m(t) is given below m(t) = 4 cos 100 pt + 8 sin 200 pt + cos 300 pt, the Nyquist sampling rate will be: (1) 1/100 (2) 1/200 (3) 1/300 (4) 1/600
Last Answer : The analog signal m(t) is given below m(t) = 4 cos 100 pt + 8 sin 200 pt + cos 300 pt, the Nyquist sampling rate will be: 1/300
Description : A theory that establishes the minimum sampling rate that can be used for a given PCM systems.
Last Answer : Nyquist sampling theorem
Description : A theory that establishes the minimum sampling rate that can be used for a given PCM systems
Description : The Ku frequency band used in satellite communication (for uplink and downlink) is: (1) 14 GHz and 11 GHz (2) 30 GHz and 20 GHz (3) 70 GHz and 50 GHz (4) 60 GHz and 45 GHz
Last Answer : The Ku frequency band used in satellite communication (for uplink and downlink) is: 14 GHz and 11 GHz
Description : The frequency range 30MHz - 300MHz is (A) medium frequency (B) very high frequency (C) super high frequency (D) Infrared frequency
Last Answer : The frequency range 30MHz - 300MHz is very high frequency
Description : In commercial FM broadcasting, the maximum frequency deviation is normally (A) 5 KHz (B) 15 KHz (C) 75 KHz (D) 200 KHz
Last Answer : In commercial FM broadcasting, the maximum frequency deviation is normally 75 KHz
Description : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is (a) > 100 (b) > 500 (c) > 1000 (d) > 20000
Last Answer : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is > 1000
Description : A rectangular waveguide is 4.2 cm by 1.85 cm. The cut-off frequency of the dominant mode through this waveguide is (a) 3.57 GHz (b) 3.75 GHz (c) 3.70 MHz (d) 3.57 MHz
Last Answer : A rectangular waveguide is 4.2 cm by 1.85 cm. The cut-off frequency of the dominant mode through this waveguide is 3.57 GHz
Description : For an antenna to be frequency-independent, it should expand or contract in proportion to the (a) gain (b) directivity (c) wavelength (d) impedance
Last Answer : For an antenna to be frequency-independent, it should expand or contract in proportion to the impedance
Description : The frequency range of FM radio is
Last Answer : The frequency range of FM radio is 88MHz to 108MHz
Description : A tuned circuit has a Q of 100 at its resonant frequency of 500 kHz. Its bandwidth is _____kHz. (A) 50000 (B) 0.2 (C) 600 (D) 5
Last Answer : A tuned circuit has a Q of 100 at its resonant frequency of 500 kHz. Its bandwidth is 5 kHz.
Last Answer : If a wave has frequency of 2 Hz, it has a period of 1/2 s.
Last Answer : In CCIR system B standard, the line frequency 15,625 lines/sec.
Last Answer : The maximum Usable Frequency is dependent on the electron density of the ionospheric layer.
Last Answer : In the telephone, the dial tone has a frequency of 33 Hz.
Description : Highest theoretical frequency that can be processed at a sampling rate without aliasing. A. Folding frequency B. Resonant frequency C. Natural frequency D. Critical frequency
Last Answer : A. Folding frequency
Description : ECE Board Exam March 1996 According to the Nyquist theorem, the sampling rate that can be used in a PCM system is ________ the highest audio frequency. A. once B. eight times C. twice D. thrice
Last Answer : C. twice
Description : The result whenever the sampling rate is less than twice the highest audio frequency.
Last Answer : alias
Description : The Nyquist theorem specifies the minimum samplingrate to be_______. A) equal to the lowest frequency of asignal B) equal to the highest frequency ofa signal C) twice thebandwidth of a signal D) twice thehighest frequencyof a signal
Last Answer : twice thehighest frequencyof a signal
Last Answer : When large amount of power is required, a push pull amplifier is designed for operation as class B.
Description : What is the advantage of PTM over PAM? A. All of these B. Low sampling rate is required C. Much better noise immunity D. Simpler to generate
Last Answer : C. Much better noise immunity
Description : Consider a CSMA/CD network that transmits data at a rate of 100 Mbps (108 bits per second) over a 1 km (kilometre) cable with no repeaters. If the minimum frame size required for this network is 1250 bytes, what is the signal speed (km/sec) in the cable? a. 8000 b. 10000 c. 16000 d. 20000
Last Answer : d. 20000
Description : Which performance parameter is the minimum amount of optical power required to achieve a specific bit-error rate (BER) in digital systems or a given signal-to-noise ratio (SNR) in analog systems?
Last Answer : Receiver sensitivity.
Description : Minimum number of bits required to represent maximum value of given analogue signal with 0.1% accuracy is: a. 8 bits b. 9 bits c. 10 bits d. 12 bits
Last Answer : 10
Description : Suppose a digitized voice channel is made by digitizing 8 kHz bandwidth analog voice signal. It is required to sample the signal at twice the highest frequency (two samples per hertz). What is the bit rate required, if it ... sample requires 8 bits? (A) 32 kbps (B) 64 kbps (C) 128 kbps (D) 256 kbps
Last Answer : (C) 128 kbps
Description : Choose which of following condition is not required for a waveguide to exist. a) The dimensions should be in accordance with desired frequency b) Cut-off frequency should be minimum 6GHz c) The shape should be spherical d) No specific condition is required for waveguide design
Last Answer : c) The shape should be spherical
Description : The minimum frequency required to eject electrons from a metallic surface is called a) Critical frequency b) Peak value of frequency c) Threshold frequency d)Photo frequency
Last Answer : c) Threshold frequency
Description : The minimum energy required to eject an electron from a metal surface is called a) Intensity b) Threshold frequency c) Work function d) Photo energy
Last Answer : c) Work function
Description : Which of the following statements best describes the auditor's responsibility regarding the detection of material errors and frauds? a. The auditor is responsible for the failure to detect material ... unrecorded transactions even if there is no evidence that material errors and frauds may exist
Last Answer : The audit should be designed to provide reasonable assurance that material errors and frauds are detected
Description : Which of the following statements best describes the auditor's responsibility to detect material errors and fraud? a. The auditor is responsible for the failure to detect material errors and ... detect unrecorded transactions even if there is no evidence that material errors and frauds may exis
Last Answer : The audit should be designed to provide reasonable assurance that material errors and fraud are detected.
Description : If you are required to monitor the speed of a device with a stroboscope over an extended period of time, what step should be taken to prolong the life of the flasher tube?
Last Answer : Monitor a submultiple frequency to prolong the flasher-tube life.
Description : A 10A DC Ammeter has a resistance of 0.1 Ω is to be extended to 50 A, the required shunt wire is A) Manganin wire of 20 m Ω B) Constantan wire of 20 m Ω C) Manganin wire of 25 m Ω D) Constantan wire of 25 m Ω
Last Answer : A 10A DC Ammeter has a resistance of 0.1 Ω is to be extended to 50 A, the required shunt wire is Manganin wire of 25 m Ω
Description : Which of the following statements are true? a. The larger the sample size, the greater the sampling error b. The more categories or breakdowns you want to make in your data analysis, the larger ... the larger the sample needed d. As sample size decreases, so does the size of the confidence interval
Last Answer : b. The more categories or breakdowns you want to make in your data analysis, the larger the sample needed
Description : Which of the following statement is false? Modulation is used to: (1) Reduce the bandwidth used (2) Separate differing transmissions (3) Ensure that intelligence may be transmitted over long distances (4) Allow the use of practicable antennas
Last Answer : Which of the following statement is false? Modulation is used to: Reduce the bandwidth used
Description : Indicate which one of the following is NOT an advantage of FM over AM? (1) Better noise immunity is provided (2) Lower bandwidth is required (3) The transmitted power is more useful (4) Less modulating power is required
Last Answer : Indicate which one of the following is NOT an advantage of FM over AM? (1) Better noise immunity is provided (2) Lower bandwidth is required (3) The transmitted power is more useful (4) Less modulating power is required
Description : Theoretical bandwidth requirement for FM system is: (1) Same as that of the modulating signal bandwidth (2) Twice of modulating signal Bandwidth (3) Thrice as of modulating signal Bandwidth (4) Infinite
Last Answer : Theoretical bandwidth requirement for FM system is: Infinite
Description : The disadvantage of CDMA system is: (1) Higher MAI with more user count. (2) That it needs least power consumption. (3) That it needs coherent signal. (4) That it is not suitable with PSK systems
Last Answer : The disadvantage of CDMA system is: Higher MAI with more user count.