Description : What is added to a sawtooth generator to produce a trapezoidal wave?
Last Answer : A resistor.
Description : Increasing gate length in a sawtooth generator does what to linearity?
Last Answer : Decreases linearity.
Description : Justify the need of current time base generator to obtain the specified sawtooth waveform with one example.
Last Answer : Justification:- * Current Time base generator is a circuit where the output current is a linear function of time over a specified time interval. * Time base circuits are used by radar systems to determine ... the time. * The diode D does not conduct during the sweep, because it is reverse biased.
Description : Which RC network provides better frequency stability, three-section or four-section?
Last Answer : Four-section.
Description : RC time constant characteristics, as shown in the illustration, are important in _____________. EL-0086 A. bridge rectifiers for alternator excitation B. timing and pulse shaping circuits C. transistor power amplifier biasing D. motor controller overload protection
Last Answer : Answer: B
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
Description : Harmonic distortion of the signal is produced in an RC coupled transistor amplifier. The probable component responsible for this distortion is (A) The transistor itself (B) the power supply Vcc (C) the coupling capacitor Cc (D) the biasing resistors
Last Answer : Harmonic distortion of the signal is produced in an RC coupled transistor amplifier. The probable component responsible for this distortion is The transistor itself
Description : Which of the wave shapes shown in the illustration is termed a ramp or sawtooth wave? EL-0088 A. A B. B C. C D. D
Description : Should the capacitance of the photodetector be kept small or large to prevent the RC time constant from limiting the response time?
Last Answer : Small
Description : What is the RC time constant of a series RC circuit that contains a 12-megohm resistor and a 12-microfarad capacitor?
Last Answer : 144 seconds (t=R x C)
Description : What is the difference between an RC and an RL differentiator in terms of where the output is developed? is developed?
Last Answer : . In an RC circuit the output is taken across the resistor. In the RL circuit the output is taken across the inductor.
Description : When is a second RC filter stage used?
Last Answer : When ripple must be held at an absolute minimum.
Last Answer : When ripple must be held at an absolute minimum
Description : Is an RC filter used when a large current or a small current demand is required?
Last Answer : Small.
Description : What is the voltage drop across the resistor in an RC charging circuit when the charge on the capacitor is equal to the battery voltage?
Last Answer : Zero.
Description : At what instant does the greatest voltage appear across the resistor in a series RC circuit when the capacitor is charging?
Last Answer : At the instant of the initiation of the action.
Description : Check in a centrifugal pump is (A) Provided in the discharge line (B) Generally a globe valve (C) Provided to prevent liquid from backing up through the pump when the pump is turned off or accidently stops running (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Which transistor configuration has a current gain of less than 1?
Last Answer : Common base.
Description : What method for checking transistors is cumbersome when more than one transistor is bad in a circuit?
Last Answer : The substitution method.
Description : Normally, the FIRST step in troubleshooting a transistor circuit card is to _____________. A. carefully remove the transistors from the card B. give the circuit an initial test with a signal generator C. test for continuity with a low voltage DC supply D. visually inspect the card
Last Answer : Answer: D
Description : What are the factors that limit the frequency response of a transistor amplifier?
Last Answer : The capacitance and inductance of the circuit and the interelectrode capacitance of the transistor.
Description : When you are using an ohmmeter to test a transistor for leakage, what is indicated by a low, but not shorted, reverse resistance reading?
Last Answer : A leaking transistor
Description : When you are testing the gain of an audio-frequency transistor with an ohmmeter, what is indicated by a 10-to-1 resistance ratio?
Last Answer : Normal gain.
Description : What are two transistor tests that can be done with an ohmmeter?
Last Answer : Gain and junction resistance.
Description : How is the collector lead identified on an oval-shaped transistor?
Last Answer : By the wide space between the collector lead and the other two leads (emitter and base)
Description : What safety precaution must be taken before replacing a transistor?
Last Answer : The power must be removed from the circuit.
Description : Which transistor configuration has the highest input resistance?
Last Answer : Common collector.
Description : What is the greatest danger to a transistor?
Last Answer : Heat.
Description : List three items of information normally included in the general description section of a specification sheet for a transistor.
Last Answer : The kind of transistor, the transistor's common applications, and mechanical data
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 : Name the two current loops in a transistor.
Last Answer : The base current loop and the collector current loop
Description : What is the relationship between the polarity of the voltage applied to the PNP transistor and that applied to the NPN transistor?
Last Answer : The polarity of voltage applied to the PNP transistor is opposite of that applied to the NPN
Description : What are the majority current carriers in a PNP transistor?
Last Answer : Holes.
Description : What percentage of current in an NPN transistor reaches the collector?
Last Answer : 98 percent.
Description : In the NPN transistor, what section is made very thin compared with the other two sections?
Last Answer : The P or base section.
Description : Which transistor configuration provides a phase reversal between the input and output signals?
Last Answer : Common emitter.
Description : What are the three transistor configurations?
Last Answer : Common emitter (CE), common base (CB), and common collector (CC)
Description : To properly bias an NPN transistor, what polarity voltage is applied to the collector, and what is its relationship to the base voltage?
Last Answer : Positive, more positive.
Description : What is one of the most important parts of any transistor manufacturing process?
Last Answer : Quality control.
Description : What was the name of the very first transistor?
Last Answer : Point-contact.
Description : In which direction does the arrow point on an NPN transistor?
Last Answer : Outward.
Description : What electronic function made the transistor famous?
Last Answer : Amplification.
Description : The base of a transistor serves a purpose similar to what element of the FET
Last Answer : Gate.
Description : What is one of the primary advantages of the FET when compared to the bipolar transistor?
Last Answer : High input impedance.
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 : Why is a high-gain transistor used in the phase-shift oscillator?
Last Answer : Because of the losses encountered in the RC networks.
Description : What are the three basic configurations of transistor oscillators?
Last Answer : Common collector (CC), common emitter (CE), and common base (CB).
Description : As a transistor ages, what happens to the leakage current?
Last Answer : It tends to increase
Description : Which junction of the transistor in the common-emitter detector detects the modulation envelope?
Last Answer : Emitter-base junction
Description : What three functions does the transistor in a regenerative detector serve?
Last Answer : Oscillator, mixer, and detector.