Which of the reception problems below that is not due to multipath?
Which of the reception problems below that is not due to multipath?
Coupling into and out of a traveling-wave tube can be accompanied by a
Coupling into and out of a traveling-wave tube can be accompanied by a
A magnetron is operated at a duty cycle of 0.001. It has a peak power output of 100 kilo-watts. Its average power is
A magnetron is operated at a duty cycle of 0.001. It has a peak power output of 100 kilo-watts. Its average power is
In a pulsed radar set, the STC circuit is used to
In a pulsed radar set, the STC circuit is used to
The aquadag coating on the inside of PPI tube is used
The aquadag coating on the inside of PPI tube is used
Oscillators of a klystron tube are maintained
Oscillators of a klystron tube are maintained
Which of the following permits a microwave signal to travel in one direction with virtually no loss, but severely attenuates any signal attempting to travel in the reverse direction?
Which of the following permits a microwave signal to travel in one direction with virtually no loss, but severely attenuates any signal attempting to travel in the reverse direction?
Rainfall is an important factor for fading of radio waves at frequencies above
Rainfall is an important factor for fading of radio waves at frequencies above
A high-power microwave pulse of the order of megawatts can be generated by a
A high-power microwave pulse of the order of megawatts can be generated by a
As the electron beam moves through a klystron’s intercavity drift space
As the electron beam moves through a klystron’s intercavity drift space
The resonant frequency of a cavity resonator depends upon
The resonant frequency of a cavity resonator depends upon
Theoretically electromagnetic radiation field strength varies in inverse proportion to the square of the distance, but when atmospheric attenuation effects and the absorption of the terrain are taken into account the attenuation can be as high as the inverse ___________ power of the distance.
Theoretically electromagnetic radiation field strength varies in inverse proportion to the square of the distance, but when atmospheric attenuation effects and the absorption of the terrain are taken into account the attenuation can be as high as the inverse ___________ power of the distance.
What ferrite device can be used instead of duplexer of isolate microwave transmitter and receiver when both are connected to the same antenna?
What ferrite device can be used instead of duplexer of isolate microwave transmitter and receiver when both are connected to the same antenna?
Which of the following operating frequencies is used for the modern loran navigational system?
Which of the following operating frequencies is used for the modern loran navigational system?
If the instantaneous RF potentials on the two sides of a magnetron cavity are of opposite polarity, the operation is in the
If the instantaneous RF potentials on the two sides of a magnetron cavity are of opposite polarity, the operation is in the
If k-factor is greater than 1, the array beam is bent
If k-factor is greater than 1, the array beam is bent
__________ is the progressive decrease of signal strength with increasing distance.
__________ is the progressive decrease of signal strength with increasing distance.
The frequency of the oscillation generated by a magnetron, is mainly determined by
The frequency of the oscillation generated by a magnetron, is mainly determined by
What allow microwave to pass in only one direction?
What allow microwave to pass in only one direction?
In a pulsed radar set, the function of the duplexer is to
In a pulsed radar set, the function of the duplexer is to
The cavity resonator
The cavity resonator
The coarse frequency adjustment of a reflex klystron is accomplished by
The coarse frequency adjustment of a reflex klystron is accomplished by
What is the purpose of the electromagnetic field which surrounds a traveling-wave tube?
What is the purpose of the electromagnetic field which surrounds a traveling-wave tube?
In an SHF pulsed radar set, a reflex klystron can be used as a
In an SHF pulsed radar set, a reflex klystron can be used as a
Klystron oscillators are most often used in the frequency range of
Klystron oscillators are most often used in the frequency range of
It is possible to increase the maximum range of a radar equipment by
It is possible to increase the maximum range of a radar equipment by
If the duration of the radar transmitted pulse, on a particular range of operation, is increased, the required bandwidth of the receiver’s IF amplifiers
If the duration of the radar transmitted pulse, on a particular range of operation, is increased, the required bandwidth of the receiver’s IF amplifiers
The main frequency determining element of a klystron is
The main frequency determining element of a klystron is
A shipboard equipment which measures the distance between the ship’s bottom and the ocean floor.
A shipboard equipment which measures the distance between the ship’s bottom and the ocean floor.
Calculate the effective earth’s radius if the surface refractivity is 301.
Calculate the effective earth’s radius if the surface refractivity is 301.
The antenna separations (in meters) required for optimum operation of a space diversity system can be calculated from:
where R = effective earth radius (m) and L = path length (m)
The antenna separations (in meters) required for optimum operation of a space diversity system can be calculated from:
where R = effective earth radius (m) and L = path length (m)
The highest frequency which a conventional vacuum tube oscillator can generate is not limited by the
The highest frequency which a conventional vacuum tube oscillator can generate is not limited by the
In a radar-set receiver, the usual mixer stage is
In a radar-set receiver, the usual mixer stage is
Microwave frequencies are normally regarded as those in the range of
Microwave frequencies are normally regarded as those in the range of
Which of the following is used as a high power microwave oscillator?
Which of the following is used as a high power microwave oscillator?
The Gunn diode oscillator
The Gunn diode oscillator
A thin layer of dirt and grime coverts the reflecting surface of the parabolic dish of a radar set. The particular effect on the performance of the radar will be
A thin layer of dirt and grime coverts the reflecting surface of the parabolic dish of a radar set. The particular effect on the performance of the radar will be
To achieve good bearing resolution when using a pulsed-radar set, an important requirement is
To achieve good bearing resolution when using a pulsed-radar set, an important requirement is
In microwave transmission using digital radio, what causes most intersymbol interference?
In microwave transmission using digital radio, what causes most intersymbol interference?
When it is desired that short-range targets be clearly seen on a pulsed-radar set, it is important that the receiver and display system have
When it is desired that short-range targets be clearly seen on a pulsed-radar set, it is important that the receiver and display system have
Which of the following is used as an oscillator device in the SHF band?
Which of the following is used as an oscillator device in the SHF band?
A reflex klystron is oscillating at the frequency of its resonant cavity. If the reflector voltage is made slightly less negative, the
A reflex klystron is oscillating at the frequency of its resonant cavity. If the reflector voltage is made slightly less negative, the
When used in conjunction with a radar set, the purpose of an echo box is to provide an artificial target.
When used in conjunction with a radar set, the purpose of an echo box is to provide an artificial target.
Which causes multipath or frequency selective fading?
Which causes multipath or frequency selective fading?
A Class-S Emergency Position-Indicating Radio Beacon (E.P.I.R.B)
A Class-S Emergency Position-Indicating Radio Beacon (E.P.I.R.B)
The maximum usable range of the usual radar set (on any particular range setting) is determined by
The maximum usable range of the usual radar set (on any particular range setting) is determined by
What do you call an attenuation that occurs over many different wavelengths of the carrier?
What do you call an attenuation that occurs over many different wavelengths of the carrier?
A PPI cathode-ray tube as used on a radar set
A PPI cathode-ray tube as used on a radar set
A traveling-wave tube (TWT) amplifies by virtue of
A traveling-wave tube (TWT) amplifies by virtue of
At what position is the input signal inserted into a traveling-wave tube?
At what position is the input signal inserted into a traveling-wave tube?
