Description : How do uhf tubes counter the effects of transit time?
Last Answer : By reducing the spacing between tube elements.
Description : How does transit time affect the relationship of the grid voltage and the plate current at high frequencies?
Last Answer : Transit time causes the grid voltage and plate current to be out of phase
Description : In what range of frequencies are most omnidirectional horizontally polarized antennas used? A. VHF, UHF B. VLF, LF C. SH, EHF D. MF, HF
Last Answer : A. VHF, UHF
Description : Troposheric scatter uses the frequencies in the ________ band. A. VLF B. UHF C. VHF D. UF
Last Answer : B. UHF
Description : What range of frequencies are usually referred to as the Ultra High Frequency (UHF) Band? w) 3 to 30 Mega Hertz x) 30 to 300 Mega Hertz y) 300 to 3,000 Mega Hertz z) 30,000 to 300,000 Mega Hertz
Last Answer : ANSWER: Y -- 300 to 3,000 MEGA HERTZ
Description : What range of frequencies are usually referred to as the UHF Band? w) 3 to 30 Megahertz x) 30 to 300 Megahertz y) 300 to 3,000 Megahertz z) 30,000 to 300,000 Megahertz
Last Answer : ANSWER: Y -- 300 TO 3,000 MEGAHERTZ
Last Answer : Frequencies in the UHF range propagate by means of space wave.
Description : A triode amplifier similar to the one shown in figure 1-19 has an Ebb -conditions, 1.5 milliamperes of current conducts through the tube. What w
Last Answer : +275 volts
Description : Why the control grid of a triode amplifier is negatively biased?
Last Answer : To prevent them from drawing grid current.
Description : What component is used in a triode amplifier to convert variation in
Last Answer : A plate load resistor RL
Description : What is the primary difference between a diode and a triode?
Last Answer : The triode contains a third element called the control rid.
Description : Trade-offs between competing effects are necessary for high speed response. Which competing effect (fast transit time, low capacitance, or high quantum efficiency) requires a thin active area?
Last Answer : Fast transit time.
Description : Which of the following types of noise becomes of great importance at frequencies? A. Shot noise B. Random noise C. Impulse noise D. Transit-time noise
Last Answer : D. Transit-time noise
Description : What type of uhf tube was developed to handle large amounts of power?
Last Answer : Planar
Description : 267 .Double knives movers offers advantage over conventional mower are a)Double knife are dynamically balanced b) They can be operated at higher forward speeds then conventional mower c)They produce more uniform stubble height d)All of the above
Last Answer : d)All of the above
Description : What causes dc bias energy to be absorbed by avalanche electrons and given up to the microwave field applied to an avalanche transit-time diode?
Last Answer : The negative-resistance property.
Description : What is the junction arrangement of the original avalanche transit-time diode?
Last Answer : Pnin.
Description : What characteristic of a gunn oscillator is inversely proportional to the transit time of the domain across the semiconductor?
Last Answer : The frequency.
Description : Who invented the triode ?
Last Answer : Scientist The Forest Triode discovers the triode.
Description : What is a vacuum triode ? What is a vacuum triode ?
Last Answer : A vacuum tube with three electrodes is called a triode.
Description : Which one among the following components can not be developed within an "integrated circuit"? (1) Diode (2) Triode (3) Transformer (4) Transistor
Last Answer : (3) Transformer Explanation: Some components like transformers and inductors cannot be integrated into an IC except for very specialized high frequency applications. They have to be ... circuit boards as separate components and cannot be integrated into semiconductor based integrated circuits.
Description : A triac thyristor functions as a control device and is basically ________________. A. two NPN transistors in parallel with a common base lead B. a diode in series with a temperature sensitive capacitor C. two ... -back SCR's with a common gate lead D. a triode tube with an extra heavy grid element
Last Answer : Answer: C
Description : Which one among the following components can not be developed within an “integrated circuit”? (1) Diode (2) Triode (3) Transformer (4) Transistor
Last Answer : Transformer
Last Answer : The voltage gain of triode depends on plate voltage.
Description : What type of insulator works well at very high frequencies?
Last Answer : A shorted quarter-wave section called a metallic insulator.
Description : At very high frequencies, what characteristics are displayed by ordinary insulators?
Last Answer : The characteristics of the dielectric of a capacitor.
Description : . Why are coaxial lines more efficient at microwave frequencies than two-wire transmission lines?
Last Answer : The electromagnetic fields are completely confined
Description : A cavity that vibrates at its natural frequency produces a louder sound than at other frequencies. What term is used to describe this phenomenon?
Last Answer : Resonance.
Description : What type filter is used to block the passage of current for a narrow band of frequencies, while allowing current to flow at all frequencies above or below this band?
Last Answer : . Band-reject.
Description : What type filter is used to allow a narrow band of frequencies to pass through a circuit and attenuate all other frequencies above or below the desired band?
Last Answer : Bandpass.
Description : What term is used to describe the frequency at which the filter circuit changes from the point of rejecting the unwanted frequencies to the point of passing the desired frequencies?
Last Answer : Frequency cutoff (fco).
Description : What is the filter called that passes low frequencies but rejects or attenuates high frequencies?
Last Answer : Low-pass filter, high-frequency discriminator or high-frequency attenuator.
Description : What is the filter called in which the low frequencies do not produce a useful voltage?
Last Answer : High-pass filter, low-frequency discriminator, or low-frequency attenuator.
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 is the band of frequencies called that is included between the two points at which current falls to 70 percent of its maximum value in a resonant circuit?
Last Answer : Bandwidth of the circuit
Description : How does fog affect radio waves at frequencies above 2 gigahertz?
Last Answer : It can cause attenuation by absorbtion.
Description : When a wide band of frequencies is transmitted simultaneously, each frequency will vary in the amount of fading. What is this variable fading called?
Last Answer : Selective fading.
Description : Receiver bandwidth is defined as those frequencies spread between what two points of the receiver response curve?
Last Answer : Half-power points.
Description : What IF frequencies are normally used in radar receivers
Last Answer : Thirty or sixty megahertz.
Description : What transmitter component allows the radiation of a large number of discrete frequencies over a wide band?
Last Answer : . Frequency synthesizer.
Description : Why do 2D air-search radars use relatively low carrier frequencies and low pulse-repetition rates?
Last Answer : Increased maximum range.
Description : Is it possible for a transmission line to operate improperly at certain frequencies and properly at others?
Last Answer : Yes, it is quite common.
Description : What device sweeps a band of frequencies to determine frequencies and amplitudes of each frequency component?
Last Answer : Spectrum analyzer.
Description : At frequencies above 100 megahertz, the intrinsic (i) region causes a pin diode to act as what?
Last Answer : Variable resistance.
Description : The cavities of a multicavity klystron are tuned to slightly different frequencies in what method of tuning?
Last Answer : Stagger tuning.
Description : When using frequencies above 30 megahertz, you are normally limited to using what range?
Last Answer : Line of sight.
Description : What frequencies are provided through the back-panel BNC?
Last Answer : 1 MHz and 10 MHz.
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 : What is an advantage of using horizontal polarization at high frequencies?
Last Answer : Less interference is experienced by man-made noise sources
Description : What type of polarization should be used at medium and low frequencies?