Description : What are the two teletypewriter modes of operation?
Last Answer : Synchronous and nonsynchronous
Description : What are the two main sources of emi with which radio waves must compete?
Last Answer : Natural and man-made interference.
Description : Which radio frequency bands use the tropospheric scattering principle for propagation of radio waves?
Last Answer : Vhf and above
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 : 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 : How is the term "temperature inversion" used when referring to radio waves?
Last Answer : It is a condition where layers of warm air are formed above layers of cool air.
Description : How does fog affect radio waves at frequencies above 2 gigahertz?
Last Answer : It can cause attenuation by absorbtion.
Description : How do raindrops affect radio waves?
Last Answer : They can cause attenuation by scattering.
Description : What happens to the radio wave if the luf is too low?
Last Answer : When luf is too low it is absorbed and is too weak for reception.
Description : What is the skip zone of a radio wave?
Last Answer : A zone of silence between the ground wave and sky wave where there is no reception.
Description : There is a maximum frequency at which vertically transmitted radio waves can be refracted back to Earth. What is this maximum frequency called?
Last Answer : Critical frequency.
Description : What factor determines whether a radio wave is reflected or refracted by the ionosphere?
Last Answer : Thickness of ionized layer.
Description : What is the primary difference between the radio horizon and the natural horizon?
Last Answer : Sea water.
Description : What is the determining factor in classifying whether a radio wave is a ground wave or a space wave?
Last Answer : Whether the component of the wave is travelling along the surface or over the surface of the earth.
Description : Which layer of the atmosphere has relatively little effect on radio waves?
Last Answer : Stratosphere.
Description : What is the term used to describe the basic frequency of a radio wave?
Last Answer : Fundamental frequency.
Description : What is one of the major reasons for the fading of radio waves which have been reflected from a surface?
Last Answer : Shifting in the phase relationships of the wave.
Description : What is the term used to describe a whole number multiple of the basic frequency of a radio wave?
Last Answer : Harmonic frequency or harmonics.
Description : What connecting link is used to transfer energy from a radio transmitter to its antenna located on
Last Answer : Transmission line.
Description : What type of amplifier would be used to amplify the signal from a radio antenna?
Last Answer : An rf voltage amplifier.
Description : What type of junctions are formed where the arms of a hybrid ring meet the main ring?
Last Answer : Basic E-type junctions.
Description : What are the two main categories of maintenance?
Last Answer : Preventive and corrective maintenance.
Description : What is the main reason for using a multispeed synchro system instead of a single-speed synchro system?
Last Answer : Greater accuracy without the loss of self-synchronous operation.
Description : Which of the two main types of rotors can have either a single winding or three Y-connected windings?
Last Answer : The drum or wound rotor.
Description : What are the three main parts of CRT?
Last Answer : a. Electron gun. b. Deflection system
Description : What is the main disadvantage of parallel transfer?
Last Answer : Requires more circuitry.
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 main reason for grounding the return side of the transformer to the chassis?
Last Answer : To eliminate shock hazard.
Description : What are the two main disadvantages of an LC capacitor filter?
Last Answer : Cost and size of the inductor.
Description : What main advantage does a bridge rectifier have over a conventional full-wave rectifier?
Last Answer : The bridge rectifier can produce twice the voltage with the same size transformer.
Description : What is the main disadvantage of a conventional full-wave rectifier?
Last Answer : Peak voltage is half that of the half-wave rectifier.
Description : What is the main difference in the energy arrangement between an isolated atom and the atom in a solid?
Last Answer : The energy levels of an atom in a solid group together to form
Description : What are the four main classes of regular variation which affect the extent of ionization in the ionosphere?
Last Answer : Daily, seasonal, 11-year, and 27-days variation
Description : What is the main difference between these two types of variations?
Last Answer : . Regular variations can be predicted but irregular variations are unpredictable
Description : What three main factors determine the amount of refraction in the ionosphere?
Last Answer : (a) density of ionization of the layer (b) frequency (c) angle at which it enters the layer
Description : What is the major difference between the electronics dry-air branch and the vital service lp air main?
Last Answer : Degree of dehydration.
Description : What is the main cause of intermodulation distortion?
Last Answer : Close spacing of transmitters and receivers.
Description : What is the main difference between a vu and a dB meter?
Last Answer : DB meters are used for measuring sine waves. Vu meters are used to measure the average value of complex waveforms.
Description : . What are the two main disadvantages of an LC capacitor filter?
Last Answer : Cost of the inductor and size of the inductor.
Last Answer : Reduce the cost of manufacturing equipment.
Last Answer : The bridge rectifier can produce double the voltage with the same size transformer.
Description : What is the main disadvantage of the conventional full wave rectifier?
Last Answer : The peak voltage is half that of a half-wave rectifier.
Description : What is the main difference between the Armstrong oscillator and the Hartley oscillator?
Last Answer : Feedback coil. Armstrong uses a separate coil. Hartley uses a tapped coil.
Description : What are the main causes of coupling loss?
Last Answer : Poor fiber end preparation and poor fiber alignment.
Description : What is the main factor that determines receiver sensitivity?
Last Answer : Noise
Description : List the main types of receiver noise.
Last Answer : Thermal noise, dark current noise, and quantum noise
Description : What are four main causes of tape failure?
Last Answer : Normal wear, accidental damage, environmental damage, and winding errors.
Description : The control electronics component of a floppy or hard disk drive performs what three main functions?
Last Answer : a. Spins the disk at the correct speed. b. Moves the heads across the recording surface. c. Tells the write/read heads when to write data and when to read it.
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 main advantage of radiotelegraph communications?
Last Answer : Reliability.