Description : What is the most common form of coupling for an rf amplifier?
Last Answer : Transformer coupling.
Description : What two methods are used to compensate for the problems that cause low gain in an rf amplifier?
Last Answer : . RF transformers are used and the transistor is neutralized.
Description : If the rf amplifier discussed has an 80 milliwatt input, what would be the maximum output?
Last Answer : 800 watts.
Description : What type coupling is usually used to couple the output from a power amplifier?
Description : Which of the following methods cannot be used to increase the bandwidth for cascaded RF amplifier stages? A) Wave traps in each stage B) Stagger tuning C) A shunt damping resistor across each tuned circuit D) Doubled tuned transformers with tighter coupling
Last Answer : A) Wave traps in each stage
Description : What problem is caused in an rf amplifier by a loosely coupled transformer?
Last Answer : A too-narrow bandpass.
Description : Can a parallel LC circuit be used as the frequency determining network for an rf amplifier?
Last Answer : Yes.
Description : What is the purpose of a frequency-determining network in an rf amplifier?
Last Answer : To provide maximum impedance at the desired frequency.
Description : What is the result of pulsing a pulsed rf amplifier when no rf is present?
Last Answer : Oscillations at an undesired frequency.
Description : For what class of operation is the final rf power amplifier of a plate-modulator circuit biased?
Last Answer : Class C
Description : Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave? A. AF amplifier B. Antenna C. Detector D. Crystal
Last Answer : B. Antenna
Description : Calculate the noise figure of the receiver whose RF amplifier has an input resistance of 1000Ω and an equivalent shot-noise resistance of 2000Ω, a gain of 25 and load resistance of 125 kΩ. Given that the bandwidth is 1. ... to an antenna with an impedance of 75Ω. A. 30.3 B. 3.03 C. 303 D. .303
Last Answer : A. 30.3
Description : If the output impedance of an amplifier circuit is decreased, what is the effect on the gain?
Last Answer : The gain decreases.
Description : What type coupling would be most useful for an audio amplifier between the first and second stages?
Last Answer : RC coupling.
Description : One of the following is a high powered RF ac basic transmitter that has two or more stages, the oscillator stage which determines the frequency opereation and RF amplifier stage orstages that develop the ... to develop a good frequency stability. A. Goldsmith B. MOPA C. Alexanderson D. Hartley
Last Answer : B. MOPA
Description : What are four methods of coupling amplifier stages?
Last Answer : Direct, RC, impedance, and transformer coupling.
Description : What is the purpose of an amplifier-coupling network?
Last Answer : To transfer energy (a signal) from one stage to another.
Description : In a resistance loaded, RC coupled amplifier the dc component is blocked by A) Load resistance RL B) Coupling capacitor, CC C) RB D) The transistor.
Last Answer : B) Coupling capacitor, CC
Last Answer : For an amplifier, the coupling method which gives the highest gain is Transformer coupling.
Description : What component in an amplifier circuit tends to limit the low-frequency response of the amplifier?
Last Answer : The coupling capacitor (C3).
Description : What component is used in a triode amplifier to convert variation in
Last Answer : A plate load resistor RL
Description : If the input-signal-developing impedance of an amplifier is increased, what is the effect on the gain?
Last Answer : The gain increases.
Description : If the unity-gain point of the operational amplifier used in question 24 is 500 kilohertz, what is the bandwidth of the circuit?
Last Answer : 50 kilohertz (Gain = 10; Gain-Bandwidth Product = 500,000) 500,000(Hz)
Description : What happens to the overall gain of a lin-log amplifier as each stage saturates?
Last Answer : Decreases.
Description : The main component responsible for the fall of gain of an RC coupled amplifier in low frequency range is (A) The active device itself (tube, or transistor) (B) stray shunt capacitance Cs (C) the grid leak resistance Rg (D) coupling capacitor Cc
Last Answer : The main component responsible for the fall of gain of an RC coupled amplifier in low frequency range is coupling capacitor Cc
Description : When measuring a transmitter’s frequency against a suitable standard, the frequency to be measured is taken from the A. oscillator stage B. intermediate amplifier C. buffer stage D. final RF stage
Last Answer : D. final RF stage
Description : What is the meaning of forward power? A. The power traveling from the transmitter to the antenna. B. The power radiated from the top of an antenna system. C. The power produced during the positive half of an RF cycle. D. The power used to drive a linear amplifier.
Last Answer : A. The power traveling from the transmitter to the antenna.
Description : What establishes the receiver bandwidth? A. RF amplifier B. Mixer C. Local oscillator D. IF amplifier
Last Answer : D. IF amplifier
Description : What consists the front-end circuit of a VHF TV superheterodyne receiver? A. Mixer, RF amplifier and AFC? B. RF amplifier, Band pass filter and mixer C. Local oscillator, mixer and RF amplifier D. Local oscillator, AGC and antenna
Last Answer : C. Local oscillator, mixer and RF amplifier
Description : One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency ... capacitor in the oscillator D. Loose connections in the oscillator, amplifier, or antenna circuits.
Last Answer : D. Loose connections in the oscillator, amplifier, or antenna circuits.
Description : Refers to one of the front end circuit of a VHF TV superheterodyne receiver which is usually a separate circuit coupled to the mixer. A. Antenna feed B. AGC C. RF amplifier D. Local oscillator
Last Answer : D. Local oscillator
Description : Which of the following is one of the possible causes for a slow drift of frequency in a self exited transmitter oscillator circuits resulting to a poor frequency stability? A. Poor soldered connections ... , or antenna circuits D. DC and RF heating of resistors, causing then to change values.
Last Answer : D. DC and RF heating of resistors, causing then to change values.
Description : After the IF stages have been aligned, the next stage to align in FM receiver is. A. local oscillator B. limiter stage C. RF amplifier D. mixer stage
Last Answer : A. local oscillator
Description : In a Klystron amplifier, the RF voltage produces (a) amplitude modulation (b) frequency modulation (c) phase modulation (d) velocity modulation
Last Answer : In a Klystron amplifier, the RF voltage produces velocity modulation
Description : If C4 were removed from the circuit, what would happen to the output of the amplifier?
Last Answer : The output would decrease. (C4 decouples R2 preventing degenerative feedback from R2.)
Description : In the basic transistor amplifier discussed earlier, what is the relationship between the polarity of the input and output signals?
Last Answer : The signals are opposite in polarity or 180 degrees out of phase with each other.
Description : The input and output signals of a JFET amplifier have what phase relationship?
Last Answer : They are 180 degrees out of phase.
Description : If the single-input, differential-output, differential amplifier has an output signal taken between the two output terminals, what will the peak-to-peak amplitude of this combined output be?
Last Answer : 200 millivolts. A-18. a. Differential amplifier
Description : If the differential amplifier is configured with a single input and differential outputs, what will the output signals be?
Last Answer : Each output will be a sine wave with a peak-to-peak amplitude of 100 millivolts. The output signals will be 180 degrees out of phase with each other.
Description : If the two input signals to a difference amplifier are equal in amplitude but neither in phase nor 180 degrees out of phase, what will the output signal be?
Last Answer : . A different shape than the input signals but larger in amplitude.
Description : If only one input signal is used with a difference amplifier, what will the output signal be?
Last Answer : Equal in shape and frequency to the input signal; larger in amplitude than the input signal; half as large in amplitude as when two input signals were used that were 180 degrees out of phase.
Description : If the two input signals to a difference amplifier are equal in amplitude and 180 degrees out of phase, what will the output signal be?
Last Answer : Equal in shape and frequency to each input signal and larger in amplitude by two times than
Description : . If the two input signals of a difference amplifier are in phase and equal in amplitude, what will the output signal be?
Last Answer : No output (the signals will "cancel out").
Description : What two transistor amplifier configurations are combined in the single-transistor, two-input, single-output difference amplifier?
Last Answer : Common emitter (CE) and common base (CB)
Description : In the power amplifier shown in figure 2-10, what two signals are mixed to produce the output signal?
Last Answer : Local oscillator and coherent oscillator.
Description : In the illustration, the component VR2 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to terminal ... 2 at 9.1 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC
Last Answer : Answer: C
Description : In the illustration, the component VR1 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to ... terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC
Last Answer : Answer: A
Description : An operational amplifier, as used in today's consoles, has a calculated gain of 5. This means that when the input changes _____________. A. 5 volts, the output changes 10 volts B. 10 volts, the output changes 5 volts C. 2 volts, the output changes 10 volts D. 10 volts, the output changes 2 volts
Description : When troubleshooting an amplifier, you measure an output of 30 volts. If the gain of the amplifier is 2, what must the input voltage be for the amplifier to work properly? A. 32 volts B. 30 volts C. 28 volts D. 15 volts
Last Answer : Answer: D
Description : An operational amplifier, as used in today's consoles, may have a calculated gain of 5. This means that as the input changes by ______________. A. 1 volt, the output changes 5 volts B. 5 volts, the output changes 1 volt C. 5 volts, the output changes 10 volts D. 10 volts, the output changes 5 volts