Description : The number of half-wave patterns in the "b" dimension of rectangular waveguides is indicated by which of the two descriptive subscripts?
Last Answer : Second.
Description : The field arrangements in waveguides are divided into what two categories to describe the various modes of operation?
Last Answer : Transverse electric (TE) and transverse magnetic (TM).
Description : What term is used to identify each of the many field configurations that can exist in waveguides?
Last Answer : Mode of operation.
Description : Compared to the velocity of propagation of waves in air, what is the velocity of propagation of waves in waveguides?
Last Answer : Slower.
Description : What is the primary lower-frequency limitation of waveguides?
Last Answer : Physical size.
Description : What is used as a dielectric in waveguides?
Last Answer : Air.
Description : List the two common types of waveguides in use today.
Last Answer : Cylindrical and rectangular.
Description : What mechanisms in the fiber waveguides weaken and distort the optical signal?
Last Answer : Scattering, absorption, and dispersion.
Description : What type of material is used in the construction of bolometers and thermistors?
Last Answer : Temperature-sensitive material that exhibits a large negative temperature coefficient.
Description : What is considered the most efficient mode in terms of energy transfer in waveguides? A. Dominant mode B. Normal mode C. Conventional mode D. Vertical mode
Last Answer : A. Dominant mode
Description : Best reason for pressurizing waveguides with dry air A. To maintain propagation B. To maintain temperature of the waveguide C. To reduce the possibility of internal arcing D. To increase the speed of propagation
Last Answer : C. To reduce the possibility of internal arcing
Description : The velocity of a wave travelling in the air medium without transmission lines or waveguides(wireless) is a) 6 x 10 8 b) 3 x 10 8 c) 1.5 x 10 8 d) 9 x 10 8
Last Answer : b) 3 x 10 8
Description : In waveguides, which of the following conditions will be true? a) V > c b) V < c c) V = c d) V >> c
Last Answer : a) V > c
Description : Curl cannot be employed in which one of the following? a) Directional coupler b) Magic Tee c) Isolator and Terminator d) Waveguides
Last Answer : d) Waveguides
Description : Spherical systems are employed in waveguides. State True/False a) True b) False
Last Answer : b) False
Description : Rectangular waveguides dominate the circular waveguides. Find the reason. a) Low cut-off frequency b) Easy to design c) More wave propagation d) The statement is false
Last Answer : b) Easy to design
Description : Cylindrical system is employed in waveguides. State True/False. a) True b) False
Last Answer : a) True
Description : What is the major difference in grid construction between power pentodes and conventional pentodes?
Last Answer : Conventional pentodes have a staggered grid arrangement, while power pentodes have a shielded grid arrangement.
Description : What is the main difference in construction between normal PN junction diodes and tunnel diodes?
Last Answer : The amount of doping.
Description : What is the primary difference in construction between the basic magnetron and the negativeresistance magnetron?
Last Answer : The negative-resistance magnetron has a split plate
Description : How do the two types of monolithic IC construction differ?
Last Answer : Diffusion penetrates substrate; epitaxial does not
Description : Name the two types of monolithic IC construction discussed.
Last Answer : Diffusion; epitaxial growth
Description : What is a major advantage of modular construction?
Last Answer : Rapid repair of systems and improved efficiency
Description : The way a magnetic head will be used determines how it is constructed. Name three factors that determine the final construction of a magnetic head.
Last Answer : a. Type of head (record, reproduce, or erase). b. Frequencies it will record or reproduce. c. Whether it will be used on a single or multitrack recorder.
Description : Other than the type of cell used, what is the major difference between the construction of the leadacid and nicad battery?
Last Answer : The cells in the nicad battery can be replaced.
Description : How can loss be reduced during construction (or fabrication) of optical fibers?
Last Answer : By removing the impurities from optical fiber.
Description : What type of flux must be used in all electrical and electronic soldering?
Last Answer : Noncorrosive, nonconductive rosin fluxes.
Description : Why must items to be soldered be cleaned just prior to the soldering process?
Last Answer : Solder will not adhere to dirty, greasy, or oxidized surfaces.
Description : A waveguide bend must have what minimum radius?
Last Answer : Greater than 2 wavelengths.
Description : When a waveguide is terminated in a resistive load, the load must be matched to what property of the waveguide?
Last Answer : . Characteristic impedance.
Description : For an electric field to exist at the surface of a conductor, the field must have what angular relationship to the conductor?
Last Answer : The field must be perpendicular to the conductors.
Description : . What primary condition must magnetic lines of force meet in order to exist?
Last Answer : Magnetic lines of force must form a continuous closed loop.
Description : What safety precaution must be taken before replacing a transistor?
Last Answer : The power must be removed from the circuit.
Description : What must be done to a circuit before you can use an ohmmeter for testing?
Last Answer : It must be de-energized.
Description : An instrument thAn instrumAn instrument that must be calibrated in place requires what type of calibration label?
Last Answer : SPECIAL CALIBRATION label.
Description : What calibration label is used when actual measurement values must be known to use the test equipment?
Last Answer : CALIBRATED—REFER TO REPORT.
Description : To increase the magnitude of a number by 23, you must shift the number how many times and in what direction?
Last Answer : Three to the left.
Description : What logic levels must exist for the FF to be toggled by the clock?
Last Answer : Both J and K must be HIGH.
Description : What condition must occur to have a change in the output of a D FF?
Last Answer : A positive-going clock pulse.
Description : For an R-S FF to change output conditions, the inputs must be in what states?
Last Answer : 1 and 0, or opposite states.
Description : To sort a data file, what must you tell the sort program?
Last Answer : What data field or fields to sort on.
Description : The output of the sum point must contain information that controls what two factors of load movement in a position servo?
Last Answer : Amount and direction of rotation.
Description : What must be used to test an activated circuit?
Last Answer : Approved meters or other indicating devices
Description : What safety precaution must you observe when soldering or hot-wire stripping fluoroplastic insulated wire?
Last Answer : Adequate ventilation.
Description : Why must a wiring diagram be used in conjunction with a schematic to troubleshoot a system?
Last Answer : To find the test points.
Description : Why must cables and wires be identified?
Last Answer : To provide the technician with a means to trace the wires when troubleshooting and repairing electrical and electronic systems.
Description : What are the two main sources of emi with which radio waves must compete?
Last Answer : Natural and man-made interference.
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 : 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 : To propagate energy down an arm of a hybrid ring duplexer, the two fields at the junction of the arm and the ring must have what phase relationship?
Last Answer : 180 degrees out of phase