Description : What are the three types of line losses associated with transmission lines?
Last Answer : Copper, dielectric, and radiation.
Description : What are the two types of coaxial lines in use today?
Last Answer : Air coaxial (rigid) and solid coaxial (flexible).
Description : . Why are coaxial lines more efficient at microwave frequencies than two-wire transmission lines?
Last Answer : The electromagnetic fields are completely confined
Description : List the two common types of waveguides in use today.
Last Answer : Cylindrical and rectangular.
Description : List five common fiber optic transmitter packages.
Last Answer : TO can, DIP, butterfly lead microcircuits, circuit cards, and stand-alone optical fiber converters.
Description : List five precautions to take when installing fiber optic systems on board naval ships.
Last Answer : a. Never bend an optical fiber or cable at a radius of curvature less than the minimum bend radius. b. Never pull fiber optic cables tight or fasten them over or through sharp corners or ... the hardware. e. Allow only trained, authorized personnel to install or repair fiber optic systems.
Description : List five system design parameters considered when system designers choose the system operational wavelength and link components.
Last Answer : Launch power, connection losses, bandwidth, cost, and reliability
Description : Two types of waves are formed on a transmission line. What names are given to these waves?
Last Answer : Incident waves from generator to load. Reflected waves from load back to generator.
Description : List six types of fiber mismatches.
Last Answer : Core diameter mismatch, cladding diameter mismatch, core ellipticity, core and cladding concentricity differences, NA mismatch, and refractive index profile differences.
Description : List the three types of cable designs being considered by the Navy.
Last Answer : Optical fiber cable component (OFCC), stranded, and ribbon cables designs.
Description : List the types of materials used in fabricating low-loss, long wavelength optical fibers.
Last Answer : Heavy-metal fluorides, chalcogenide glasses, and crystalline materials.
Description : List the main types of receiver noise.
Last Answer : Thermal noise, dark current noise, and quantum noise
Description : List the types of fiber optic components considered part of a fiber optic cable plant.
Last Answer : Optical fiber cables, connectors, splices, mounting panels, jumper cables, and other passive components.
Description : What is the best type of surface or terrain to use for radio wave transmission?
Last Answer : Radio horizon is about 1/3 farther.
Description : Radar altimeters use what type of transmission signal?
Last Answer : Frequency modulated (fm).
Description : What two components make up a simple synchro transmission system?
Last Answer : A synchro transmitter and a synchro receiver.
Description : How does temperature inversion affect radio transmission?
Last Answer : It can cause vhf and uhf transmission to be propagated far beyond normal line-of-sight distances.
Description : What are three ways of controlling radiated emi during transmission?
Last Answer : a) physical separation of the antenna (b) limiting bandwidth of the antenna (c) use of directional antennas
Description : What three factors must be considered in the transmission of a surface wave to reduce attenuation?
Last Answer : (a) electrical properties of the terrain (b) frequency (c) polarization of the antenna
Description : What characteristic is determined by the time required for a voltage wave to travel from the input end of an artificial transmission line to the output end and back again?
Last Answer : Pulse width
Description : The actions of the tr and atr circuits depend on the impedance characteristics of what length of transmission line?
Last Answer : Quarter-wavelength section
Last Answer : Pulse width.
Description : What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?
Last Answer : Pulse-Doppler.
Description : What transmission method does NOT depend on relative frequency or target motion?
Last Answer : Pulse modulation.
Description : Is it possible for a transmission line to operate improperly at certain frequencies and properly at others?
Last Answer : Yes, it is quite common.
Description : What are the two common causes of transmission-line deterioration?
Last Answer : Corrosive effects of salt water and weather extremes.
Description : At what points along a transmission line will a neon lamp glow the brightest?
Last Answer : At standing-wave voltage peaks.
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 : On an open-ended transmission line, the voltage is always zero at what distance from each end of the line?
Last Answer : One-fourth the distance from each end of the line.
Description : All the power sent down a transmission line from a transmitter can be transferred to an antenna under what optimum conditions?
Last Answer : When the characteristic impedance of the transmission line and the load impedance are equal.
Description : Describe the leakage current in a transmission line and in what unit it is expressed.
Last Answer : The small amount of current that flows through the dielectric between two wires of a transmission line and is expressed in micro ohms per unit length.
Description : A transmission line is said to have distributed constants of inductance, capacitance, and resistance along the line. What units of measurement are used to express these constants?
Last Answer : Inductance is expressed in micro henrys per unit length, capacitance is expressed in picofarads per unit length, and resistance is expressed in ohms per unit length.
Description : . What are two of the three physical factors that determine the values of capacitance and inductance of a transmission line?
Last Answer : (1) Type of line used, (2) dielectric in the line, and (3) length of line.
Description : What must the physical length of a transmission line be if it will be operated at 15,000,000 Hz?
Last Answer : . λ = 20 meters
Description : What type of transmission line is often used to connect a television set to its antenna?
Last Answer : Twin lead.
Description : What term is used for the end of the transmission line that is connected to an antenna?
Last Answer : Output end, receiving end, load end and sink.
Description : What term is used for the end of the transmission line that is connected to a transmitter?
Last Answer : Input end, generator end, transmitter end, sending end, and source.
Description : In swept-frequency testing the impedance of a transmission line, what electrical characteristic is actually being measured?
Last Answer : Swr on the transmission line.
Description : What is the main advantage of using a time-domain reflectometer (tdr) to test a transmission line?
Last Answer : Tdr will indicate the nature of and the distance to or location of any faults.
Description : What is the advantage of single-sideband (ssb) transmission over AM transmission?
Last Answer : The same amount of intelligence can be transmitted with one sixth of the output power with less than one-half the bandwidth.
Description : On the diagram below, name the elements of the vacuum tube and their potentials relative to dc ground. time is an example of what type of transmission?
Last Answer : a. Plate, positive. b. Suppressor grid, negative.
Description : What are two advantages of ssb transmission?
Last Answer : It saves power and frequency bandwidth.
Description : Compare the power sources of synchros and step transmission systems.
Last Answer : Synchros use ac; step transmission uses dc.
Description : What are the two emi transmission methods?
Last Answer : . Conduction and radiation.
Description : The transmission of still images over an electrical communications system is known as what?
Last Answer : Facsimile.
Description : Why has the transmission of video using analog techniques been very popular, especially for shorter distances?
Last Answer : Because cost can be minimized and complex multiplexing and timing equipment is unnecessary.
Description : What is the basic optical-material property relevant to optical fiber light transmission?
Last Answer : The index of refraction.
Description : To measure incident power, you must rotate the coupler detector of the wattmeter so that the arrow indicating power flow points toward which end of the transmission line?
Last Answer : Load.
Description : . What is the primary advantage of an fsk transmission system?
Last Answer : Resistance to noise interference.
Description : To ensure the accuracy of a transmission, what is the minimum number of times a modulating wave should be sampled in pulse modulation?
Last Answer : 2.5 times the highest modulating frequency.