Description : In a TV receiver the raster is normal but there is no sound and quality of picture is poor. The defective part is
Last Answer : AGC, video IF amplifier, RF amplifier
Description : The sound IF in a TV receiver is
Last Answer : 41.25 MHz
Description : A 4.5-MHz signal which is equal to the difference between the picture and sound RF carrier frequencies in a 6-MHz TV channel.
Last Answer : Intercarrier frequencY
Description : It is the ratio of the largest possible magnitude to the smallest possible magnitude that can be decoded by the digital-to-analog converter in the receiver.
Last Answer : Dynamic range
Description : Involves compression in the transmitter after the input sample has been converted to a linear PCM code and then expansion in the receiver prior to PCM coding:
Last Answer : Digital companding
Description : To a conventional narrowband receiver, a spread spectrum signal appears to be
Last Answer : Noise
Description : In PAM demultiplexing, the receiver clock is derived from
Last Answer : the PAM signal itself
Description : In a radio receiver with simple AGC:
Last Answer : an increase in signal strength produces more AGC
Description : Message _______ means that the receiver is ensured that the message is coming from the intended sender, not an imposter
Last Answer : authentication
Description : Photodiodes operate properly with:
Last Answer : reverse bias
Description : Both LEDs and ILDs operate correctly with:
Last Answer : Forward bias
Description : A special type of transmission line that consist of conducting metallic tube through which high frequency electromagnetic energy is propagated
Last Answer : waveguide
Description : The modulated picture carrier wave includes the composite video signal as the:
Last Answer : Symmetric envelope of amplitude variations
Description : A system where the modulated RF picture and sound carrier signals are distributed in a cable network, instead of wireless system.
Last Answer : CATV
Description : How long does it take to scan 2 picture elements when 400 are scanned in 50 microseconds?
Last Answer : 0.25 microsec
Description : Picture frames are repeated at the rate of ___ per second
Last Answer : . 30
Last Answer : 30
Description : An image uses 512 x 512 picture elements. Each element can take any of eight distinguishable levels. The maximum entropy in the above image will be:
Last Answer : 786432 bits
Description : It is used to encode the minimum amount of speech information necessary to reproduce a perceptible message with a fewer bits that those needed by a conventional encoder/decoder
Last Answer : vocoders
Description : A carrier recovery is needed with:
Last Answer : DPSK
Description : In an AM transmitter with 100% modulation, the voltage of the final RF stage will be
Last Answer : approximately four times the DC supply voltage
Description : A transmission of binary data which involves the transmission of two non – zero voltage level
Last Answer : Bipolar
Description : What is a device that provides a method of sampling energy from within a waveguide for measurement or use in another circuit?
Last Answer : Directional Coupler
Description : An integrated circuit that performs the PCM encoding and decoding functions
Last Answer : Codec
Description : Which circuit is most common to both frequency-hopping and direct-sequence spread spectrum transmitters?
Last Answer : PSN code generator
Description : A virtual circuit which is logically equivalent to a two-point dedicated private-line circuit except slower
Last Answer : Permanent Virtual Circuit
Description : The main circuit in a PSN generator is ____.
Last Answer : Shift register
Description : ____ is a virtual-circuit wide-area network that was designed in response to demands for a new type of WAN in the late 1980s and early 1990s.
Last Answer : . Frame Relay
Description : The total bandwidth of an NTSC TV signal is:
Last Answer : . 6 MHz
Description : The width of the vertical sync pulse in the Philippine TV system is
Last Answer : 3H
Description : The number of frames per second in the Philippine TV system is
Last Answer : 6 MHz
Description : To avoid objectionable noise in a microwave TV link, the SNR should be about:
Last Answer : 25 or more
Description : In a TV studio the illuminance is about:
Last Answer : 1000 lux
Description : What phenomenon will result if the glass fiber is exposed to long periods of high humidity?
Last Answer : stress corrosion
Description : “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted”
Last Answer : Plank’s law
Description : Voltage required to operate a neon-sign tube depends upon
Last Answer : Voltage required to operate a neon-sign tube depends upon length of the tube
Description : In the illustrated motor controller circuit, which statment is true? EL-0023 A. The high and low speed lights operate at less than line voltage with a resistor in series. B. This controller can be ... . The wattage of the high speed light must be greater than the wattage of the low speed light.
Last Answer : Answer: A
Description : The magnetic field of an antenna is perpendicular to the earth. The antenna’s polarization ___
Last Answer : is horizontal
Description : It is the ratio of the power density radiated in a particular direction to the power density radiated to the same point by a reference antenna, assuming both antennas are radiating the same amount of power
Last Answer : directive gain
Description : The property of interchangeability for the transmitting and receiving operations is known as ____
Last Answer : reciprocity
Description : The fields surrounding the antenna do not collapse their energy back into the antenna but rather radiate it out in space
Last Answer : radiation field
Description : It is the ratio of the radiated to the reflected energy:
Last Answer : Radiation efficiency
Description : It is the resistance that, if it replaced the antenna, would dissipate exactly the same amount of power that the antenna radiates
Last Answer : . Radiation resistance
Description : Plots of field strength or power density with respect to the value at a reference point.
Last Answer : relative radiation pattern