Description : What is the device called that will separate alternating current from direct current, or that will separate alternating current of one frequency from other alternating currents of different frequencies?
Last Answer : A filter.
Description : What effect does inductance have (a) on steady direct current and (b) on direct current while it is changing in amplitude?
Last Answer : a) No effect. (b) Inductance opposes any change in the amplitude of current.
Description : What is a disadvantage of a direct-current system with respect to supply voltage?
Last Answer : the dc voltage must be generated at the level required by the load.
Description : Define alternating current.
Last Answer : An electrical current which is constantly varying in amplitude, and which changes direction at regular intervals.
Description : Which method, vapor phase oxidation or direct-melt process, transforms deposited material into a solid glass preform by heating the porous material without melting?
Last Answer : Vapor phase oxidation.
Description : What is the major difference between direct reproduce electronics and FM reproduce electronics?
Last Answer : FM record electronics must use a limiter and demodulator circuit (figure 5-5) to demodulate the signal intelligence from the carrier frequency.
Description : How do FM record electronics differ from AM (direct record) electronics?
Last Answer : Instead of recording the signal just as it appears at the recorder’s input, FM record electronics records a frequency-modulated carrier signal from a record oscillator (figure 5-4) onto the magnetic tape
Description : The equalization and phase correction circuit in a tape recorder’s direct reproduce electronics (figure 5-2) performs what function?
Last Answer : It generates an equalization signal which corrects any frequency response problems in the input signal from the pre-amplifier circuit.
Description : The head driver circuit in a tape recorder’s direct record electronics component (figure 5-1) performs what function?
Last Answer : It takes the signal from the summing network, amplifies it, and sends it to the record head for recording.
Description : Why is direct accessing of data a big advantage over the sequential accessing of data?
Last Answer : It gives us fast, immediate access to specific data without having to examine each and every record from the beginning.
Description : What is a direct short?
Last Answer : A condition in which some point in the circuit where full system voltage is present comes in contact with the ground or return side of the circuit.
Description : Define the metal solvent action that takes place when copper conductors are soldered together.
Last Answer : The solder dissolves a small amount of the copper, which combines with the solder forming a new alloy; therefore, the joint is one common metal.
Description : Define thermal inertia.
Last Answer : The capacity of the soldering iron to generate and maintain a satisfactory soldering temperature while giving up heat to the joint being soldered.
Description : Define the term "torque."
Last Answer : A measure of how much load a machine can turn.
Description : Define matter and list its three different states.
Last Answer : Anything that occupies space and has weight. Solid, liquid, and gas.
Description : Define the term negative temperature coefficient.
Last Answer : It is the decrease in a semiconductor’s resistance as temperature rises.
Description : Define a fiber optic splice.
Last Answer : A permanent fiber joint whose purpose is to establish an optical connection between two individual optical fibers.
Description : Define the loss in optical power through a connection.
Last Answer : loss = 10log
Description : Semiconductor LEDs emit incoherent light. Define incoherent light
Last Answer : Light waves that lack a fixed-phase relationship
Description : Define responsivity.
Last Answer : The ratio of the optical detector's output photocurrent in amperes to the incident optical power in watts.
Description : Define receiver dynamic range.
Last Answer : The range of optical power levels over which the receiver operates within the specified values. It
Description : List the key operational parameters used to define receiver performance.
Last Answer : Receiver sensitivity, bandwidth, and dynamic range.
Description : Define mutual inductance.
Last Answer : Mutual inductance is the property existing between two coils so positioned that flux from one coil cuts the windings of the other coil.
Description : Define inductancanc
Last Answer : Inductance is the property of a coil (or circuit) which opposes any CHANGE in current.
Description : Define baud.
Last Answer : A unit of modulation rate.
Description : Define cladding diameter.
Last Answer : The cladding diameter is the average diameter of the cladding.
Description : Define modulation.
Last Answer : The process of varying one or more characteristics of an optical signal to encode and convey information.
Description : Extrinsic (OH) absorption peaks define three regions or windows of preferred operation. List the three windows of operation.
Last Answer : The first, second, and third windows of operation are 850 nm, 1300 nm, and 1550 nm, respectively.
Description : Define attenuation.
Last Answer : Attenuation is the loss of optical power as light travels along the fiber.
Description : Skew rays and meridional rays define different acceptance angles. Which acceptance angle is larger, the skew ray angle or the meridional ray angle?
Last Answer : Skew ray angle.
Description : Two methods describe how light propagates along an optical fiber. These methods define two theories of light propagation. What do we call these two theories?
Last Answer : The ray theory and the mode theory.
Description : Define dielectric strength.
Last Answer : The ability of the insulation material to withstand potential difference.
Description : Define the temperature coefficient of resistance.
Last Answer : The amount of increase in the resistance of a 1-ohm sample of the conductor per degree of temperature rise above 0º C
Description : Define specific resistance.
Last Answer : The resistance of a unit volume of a substance.
Description : Define a circular mil.
Last Answer : The cross-sectional area of a circular conductor with a diameter of 1 mil.
Description : Define a square mil as it relates to a square conductor
Last Answer : The cross-sectional area of a square conductor with a side of 1 mil.
Description : Define a mil-foot.
Last Answer : A circular conductor with a diameter of 1 mil and a length of 1 foot.
Description : Define insulation resistance.
Last Answer : The resistance to current leakage through the insulation.
Description : a. Define the term "working voltage" of a capacitor. b. What should be the working voltage of a capacitor in a circuit that is operating at 600 volts?
Last Answer : a. It is the maximum voltage the capacitor can work without risk of damage. b. 900 volts.
Description : Define the term "farad."
Last Answer : A farad is the unit of capacitance. A capacitor has a capacitance of 1 farad when a difference of 1 volt will charge it with 1 coulomb of electrons.
Description : Define loss.
Last Answer : Loss is the decrease in the amount of light reaching the end of the fiber.
Description : Define the heterodyne principle.
Last Answer : An impedance in which the resulting current is not proportional to the applied voltage.