Description : What is the purpose of the absorbent material in a directional coupler?
Last Answer : Absorb the energy not directed at the pick-up probe and a portion of the overall energy
Description : What is the primary purpose of a directional coupler?
Last Answer : Sampling energy within a waveguide.
Description : Which one is an antenna coupling unit? A. Coupler B. Diplexer C. Lecher wire D. Duplexer
Last Answer : B. Diplexer
Description : Not a reason for the use of an antenna coupler. A. To make the antenna look resistive B. To provide the output amplifier with the correct load impedance C. To discriminate against harmonics D. To prevent re-radiation of the local oscillator
Last Answer : D. To prevent re-radiation of the local oscillator
Description : Referred to as a ferrite device that can be used in lieu of a duplexer to isolate a microwave transmitter and receiver when both are connected to the same antenna. A. Isolator B. Circulator C. Coupler D. Diode.
Last Answer : B. Circulator
Description : One ofthe followingis not a reason forthe use of anantenna coupler: a. To make the antenna look resistive b. To provide the output amplifier with the correct load impedance c. To discriminate against harmonics d. To prevent reradiation of the local oscillator
Last Answer : d. To prevent reradiation of the local oscillator
Description : What happens to reflected energy that enters a directional coupler that is designed to sample incident energy?
Last Answer : . The reflected energy adds at the absorbent material and is absorbed.
Description : in a directional coupler that is designed to sample the incident energy, what happens to the two portions of the wavefront when they arrive at the pickup probe?
Last Answer : The wavefront portions add.
Description : How far apart are the two holes in a simple directional coupler?
Last Answer : 1/4 wavelength.
Description : Describe a directional coupler.
Last Answer : A fiber optic coupler that prevents the transfer of power between input fibers.
Description : Which type of optical splitter (Y-coupler or T-coupler) splits only a small amount of power from the input fiber to one of the output fibers?
Last Answer : T-coupler
Description : Which fiber optic component (splice, connector, or coupler) makes a permanent connection in a distributed system?
Last Answer : Splice.
Description : Why is the coupler pressurized with nitrogen?
Last Answer : To aid in heat transfer and prevent corona and arcing
Description : What are the tuning modes for the coupler group discussed?
Last Answer : Automatic, semiautomatic, and manual.
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 : A horizontally truncated paraboloid antenna is used for what purpose?
Last Answer : Determine elevation.
Description : What is the purpose of antenna stubs?
Last Answer : To produce desired phase relationship between connected elements.
Description : What composite field (composed of E and H fields) is found stored in the antenna?
Last Answer : Induction field.
Description : Which two composite fields (composed of E and H fields) are associated with every antenna?
Last Answer : Induction field and radiation field.
Description : If a transmitting antenna is placed close to the ground, how should the antenna be polarized to give the greatest signal strength?
Last Answer : Vertically polarized.
Description : The power gain of an antenna is directly related to what other antenna property?
Last Answer : Directivity.
Description : What radar component permits the use of a single antenna for both transmitting and receiving?
Last Answer : Duplexer.
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 : 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 : 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 connecting link is used to transfer energy from a radio transmitter to its antenna located on
Last Answer : Transmission line.
Description : What determines the beam elevation angle of an antenna that is electronically scanned in elevation?
Last Answer : Frequency or phase of radiated energy.
Description : What type of antenna has all elements connected to the same energy source?
Last Answer : Driven Array.
Description : What is a set of antenna elements called?
Last Answer : Antenna Array.
Description : What characteristic allows the same antenna to both transmit and receive?
Last Answer : Reciprocity.
Description : What is the term that is used to describe narrowness in the radiated beam of an antenna?
Last Answer : Antenna directivity.
Description : What type of antenna radiates in and receives energy from all directions at once?
Last Answer : Omnidirectional.
Description : What term is used to express the efficiency of an antenna?
Last Answer : Power gain or power ratio
Description : What precautions must be taken when sweeping a transmitting antenna?
Last Answer : You must ensure that power induced from any adjacent transmitting antennas does not damage your test equipment.
Description : What is the function of an antenna patch panel?
Last Answer : To connect an antenna/transmission line to a receiver/transmitter.
Description : What is the radiation pattern of a quarter-wave antenna?
Last Answer : A circular radiation pattern in the horizontal plane, or same as a half wave.
Description : What is the simplest method of feeding power to the half wave antenna?
Last Answer : To connect one end through a capacitor to the final output stage of the transmitter.
Description : In which plane will the half-wave antenna be operating if it is mounted horizontally?
Last Answer : Vertical plane.
Description : . If a basic half-wave antenna is mounted vertically, what type of radiation pattern will be produced?
Last Answer : Nondirectional.
Description : The Yagi antenna is an example of what type of array?
Last Answer : Multielement parasitic array.
Description : What is the primary reason for the development of the turnstile antenna?
Last Answer : For omnidirectional vhf communications.
Description : What is the main disadvantage of the rhombic antenna?
Last Answer : It requires a large antenna site.
Description : What is the polarity of the currents that feed the V antenna?
Last Answer : Opposite.
Description : What is another name for the Beverage antenna?
Last Answer : Wave antenna.
Description : To radiate power efficiently, a long-wire antenna must have what minimum overall length?
Last Answer : One-half wavelength.
Description : The parasitic array can be rotated to receive or transmit in different directions. What is the name given to such an antenna?
Last Answer : Rotary array.
Description : What is the radiation resistance of a half-wave antenna in free space?
Last Answer : 73 ohms.
Description : What type of polarization should be used if an antenna is mounted on a moving vehicle at frequencies below 50 megahertz?
Last Answer : Vertical polarization.
Description : The various properties of a transmitting antenna can apply equally to the same antenna when it is used as a receiving antenna. What term is used for this property?
Last Answer : Reciprocity of antennas.