Description : What are three advantages of adding an ac bias voltage to the input signal instead of adding a fixed dc bias voltage?
Last Answer : a. Reproduces a stronger output signal. b. Greatly improves the SNR. c. Greatly reduces the natural tape hiss.
Description : Why does adding dc vice ac bias voltage to the input signal result in a poor signal-to-noise ratio (SNR)?
Last Answer : With dc bias, the SNR is poor because only a small portion of the magnetism curve is straight enough to use, thus the output signal is weak compared with the natural tape hiss.
Description : Why does using ac vice dc bias voltage result in a stronger output signal?
Last Answer : Because an ac bias voltage of the proper frequency and level places the input signal away from both steps in the magnetism curve. The result is two undistorted output signals that are combined into one strong output.
Description : When measuring harmonic distortion, you set the signal generator to input a 15-kHz test signal. To what frequency should you set the wave analyzer?
Last Answer : 45 kHz.
Description : What would be the output of a negative clamper with a bias potential of −5 volts and an input voltage swing from +50 to −50 volts?
Last Answer : -5 volts.
Description : select the correct response from the choices given in the parentheses. Q-20. In a closed-loop configuration the output signal is determined by (the input signal, the feedback signal, both).
Last Answer : Both the input signal and the feedback signal.
Description : A recorder’s harmonic-distortion specification reads 2% third harmonic of a 100-kHz signal at 60 ips. What does this mean?
Last Answer : The recorder has 2% third-harmonic distortion of a 100-kHz signal at 60 ips.
Description : Which type of optical fiber (multimode or single mode) tends to have lower loss and produces less signal distortion?
Last Answer : Single mode fiber.
Description : In a circuit such as that shown in figure 3-16, if R1 has a value of 50 ohms and R2 has a value of 250 ohms and the input signal has a value of +10 millivolts, what is the value of the output signal?
Last Answer : 60 millivolts.
Description : In a circuit such as that shown in figure 3-15, if R1 has a value of 100 ohms and R2 has a value of 1 kilohm and the input signal is at a value of + 5 millivolts, what is the value of the output signal?
Last Answer : 50 millivolts.
Description : If If the input signals are 180 degrees out of phase with each other and a combined output is taken between the two output terminals, what will the amplitude of the combined output signal be?
Last Answer : 200 millivolts.
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 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 : If the output of a circuit needs to be a complete representation of one-half of the input signal, what class of operation is indicated?
Last Answer : Class B operation.
Description : What type of bias (positive or negative) is added to a negative damper for the most positive extremity of the wave shape to be clamped above 0 volts?
Last Answer : Positive bias.
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 : If the operating point of an NPN transistor amplifier is selected in saturation region, it is likely to result in A) Thermal runaway of transistor B) Clipping of output in the positive half of the ... for high dc collector supply D) Clipping of output in the negative half of the input signal
Last Answer : B) Clipping of output in the positive half of the input signal
Description : What is used to bias a magnetic amplifier so that the control winding remains free to accept control (input) signals?
Last Answer : A bias winding and associated circuitry.
Description : A, when there is an increase in the input voltage, the forward bias of Q1 increases/decreases (which one).
Last Answer : Increases.
Description : When you are testing a piece of equipment for intermodulation distortion, what should the output of the equipment look like?
Last Answer : An exact reproduction of the input.
Description : An FET has a gate source bias of 2 V. The ac input signal is ± 1.2 V. The class of operation is A) A B) B C) C D) AB
Last Answer : D) AB
Description : Each connection link in ANN is associated with ________ which has information about the input signal. A. neurons B. weights C. bias D. activation function
Last Answer : B. weights
Description : An amplifier is said to suffer from distortion when its output is - (1) low (2) different from input (3) noisy (4) larger than its input
Last Answer : (3) noisy Explanation: Amplifier Distortion can take on many forms such as Amplitude, Frequency and Phase Distortion due to Clipping. For a signal amplifier to operate correctly without any distortion to the output signal, it requires some form of DC Bias on its Base or Gate terminal.
Description : A negative damper with negative bias clamps the most positive extremity of the output wave shape to what polarity (positive or negative)?
Last Answer : Negative potential.
Description : What type damper (with bias) clamps the most negative extremity of the output waveform to a negative potential?
Last Answer : Positive clamper with negative bias.
Description : What distortion is not caused by transmission line characteristics? A. Phase distortion B. Pulse shape distortion C. Spacing bias distortion D. Amplitude distortion
Last Answer : C. Spacing bias distortion
Description : In the illustrated circuit, what is the phase relationship of the amplifier output compared to the input? EL-0022 A. 0° in-phase B. 180° out of phase C. phase angle of the input divided by power factor D. unable to determine without the value of the bias voltage
Last Answer : Answer: B
Description : The device in figure 'B' shown in the illustration can be used to control an AC load yet maintain its high gain by ______________. EL-0091 A. connecting the load to the output side of the ... connecting the load to the input side of the bridge D. reversing the current flow through the bias winding
Last Answer : Answer: C
Description : Define: i) Input Offset Voltage ii) Input offset Current iii) Input Bias Current iv) Output offset voltage
Last Answer : Definition of parameters of OPAMP is follows: i) Input Offset Voltage: Input offset voltage is defined as the voltage that must be applied between the two input terminals of an OPAMP to null or ... to ground) and output voltage is obtained non zero such voltage is output offset voltage of opamp.
Description : How can a series-positive limiter be modified to limit unwanted negative portions of the input signal?
Last Answer : Biasing.
Description : What components form the input-signal-developing impedance for the amplifier?
Last Answer : C2 and the secondary of T1.
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 : . When you select the time base to display a signal, should the time base be the same, higher, or lower than the input signal?
Last Answer : Lower.
Description : In applications where electronic waveforms are displayed on a CRT screen, the input signal is normally applied to what CRT element?
Last Answer : The vertical-deflection plate.
Description : In the inverting configuration when the noninverting input is grounded, the inverting input is at (signal, virtual) ground
Last Answer : Virtual.
Description : In the inverting configuration, what is the voltage (for all practical purposes) at the inverting input to the operational amplifier if the input signal is a 1-volt, peak-to-peak sine wave?
Last Answer : 0 volts.
Description : In the inverting configuration, the input signal is applied to the (a) (inverting, noninverting) input and the feedback signal is applied to the (b) (inverting, noninverting) input.
Last Answer : a. Inverting. b. Inverting.
Description : Does a rectifier tube conduct on the positive or negative alternation of the input signal?
Last Answer : Positive.
Description : What type of feedback aids an input signal?
Last Answer : Regenerative or positive
Description : The pump signal frequency must be of what value when compared to the input signal of a simple parametric amplifier?
Last Answer : Exactly double the input frequency.
Description : Two tape recorders have signal-to-noise ratios (SNRs) of 25-dB RMS and 35-dB RMS respectively. Which of the SNRs can record and reproduce the widest range of input signals and why?
Last Answer : 35-dB RMS because the highest SNR can always record and reproduce the widest range of input signals.
Description : rid-leak biasing in effect rectifies the input ac signal. What feature
Last Answer : Unequal charge and discharge paths of the coupling capacitor Cc.
Description : When a circuit uses cathode biasing, the input signal can cause varia
Last Answer : Through the use of a bypass capacitor
Description : Which component in figure 3-7 develops the af signal at the input?
Last Answer : R1.
Description : Does an amplifier actually change an input signal? Why or why not?
Last Answer : No, the input signal is unchanged, the output signal is controlled by the input signal but does not effect the actual input signal.
Description : Which of the following is not true: A) An oscillator is a circuit that converts DC to AC B) An oscillator is an amplifier that supplies its own input signal C) All oscillators generate sine waves D) In phase feedback is called positive Feedback
Last Answer : C) All oscillators generate sine waves
Description : What can be added to the basic two-cavity klystron to increase the amount of velocity modulation and the power output?
Last Answer : Intermediate cavities between the input and output cavities.