Description : How can a series-positive limiter be modified to limit unwanted negative portions of the input signal?
Last Answer : Biasing.
Description : If frequency of modulated wave is less than frequency of carrier wave, then input signal is A. negative B. positive C. zero D. infinite
Last Answer : negative
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 the ripple frequency of a full-wave rectifier with an input frequency of 60 Hz?
Last Answer : 120 hertz.
Description : What is the Ripple frequency of a half-wave rectifier if the input frequency is 60 Hz?
Last Answer : 60 hertz.
Description : An ac voltage is applied across a diode. The tube will conduct when
Last Answer : Positive.
Description : When used for ac current control, during which alternation of the ac cycle does the TRIAC control current flow?
Last Answer : During both alternations.
Description : What is the polarity of the first alternation of the tank circuit in an emitter-loaded npn pulsed oscillator?
Last Answer : Negative
Description : If the mu of a tube is 85 and the signal at the control grid is 4 volts ac, the plate voltage will vary by what amount?
Last Answer : 340 volts.
Description : The plate voltage of a tube will vary 126 volts when a 3-volt ac signal is applied to the control grid. What is the gain of this tube?
Last Answer : 42.
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 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : How does dc bias added to the input signal correct the distortion in the output signal?
Last Answer : The dc bias moves the input signal away from the step in the magnetism curve. This prevents the input signal from crossing the zero-point of the magnetism curve.
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 : 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 : 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 : The input signal of a travelling wave tube is introduced at A. Cathode B. Anode C. Cathode end of the helix D. Collector end of the helix
Last Answer : C. Cathode end of the helix
Description : A large negative voltage is applied to the plate of a diode, and a largewhat tube parameter has been exceeded?
Last Answer : Peak Inverse Voltage (PIV).
Description : Which portion of a sine-wave input is retained in the output of a series-negative limiter?
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 : Which portion of a sine-wave input is retained in the output of a series-positive limiter?
Last Answer : Negative.
Description : A positive damper clamps which extremity of the output signal to 0 volts?
Last Answer : Most negative.
Description : Negative feedback amplifier has a signal corrupted by noise as its input. The amplifier will (A) Amplify the noise as much as the signal (B) Reduce the noise (C) Increase the noise (D) Not effect the noise
Last Answer : Negative feedback amplifier has a signal corrupted by noise as its input. The amplifier will Reduce the noise
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 : If a voltage (positive or negative) is measured on the "1" output of a flip-flop, what state is it in?
Last Answer : SET state.
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 : 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.