Description : Which of the following statements represents the important factor that must be considered when replacing a faulty diode in the exciter rectifier assembly? A. Be certain that the replacement diode ... The replacement diode must be dipped in varnish prior to installation to protect against humidity.
Last Answer : Answer: A
Description : An ac voltage is applied across a diode. The tube will conduct when
Last Answer : Positive.
Description : The component labeled 'CR1' in the circuit shown in the illustration __________________. EL-0085 A. varies its anode/cathode polarity depending on 'RL' current B. rectifies the varying voltage from the ... reactance to smooth ripple D. establishes a constant reference voltage for the base of 'Q1'
Last Answer : Answer: D
Description : What is the relative length of the time constant for the diode capacitor combination in a damper (long or short)?
Last Answer : Short time constant.
Description : The device in figure 'B' shown in the illustration will conduct when the ____________. EL-0067 A. base-emitter is forward biased and the collector-base is reverse biased B. anode-cathode is forward ... is reversed biased D. terminal 1-2 is forward biased and the emitter-terminal 1 is reverse biased
Last Answer : Answer: B
Description : The waveform of a certain signal can be studied by – (1) Spectrometer (2) Cathode ray oscilloscope (3) p - n junction diode (4) Sonometer
Last Answer : (4) Sonometer Explanation: A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum. Cathode ray oscilloscope is an electronic display ... electron beam that is used to produce visible patterns or graphs on a phosphorescent screen.
Description : The waveform of a certain signal can be studied by (1) Spectrometer (2) Cathode ray oscilloscope (3) p – n junction diode (4) Sonometer
Last Answer : Sonometer
Description : In replacing a defective transformer with a new one, which of the following actions must be carried out to insure proper operation of the equipment it serves? A. The secondary leads must be grounded ... magnetize it. D. The iron core must be grounded for 10 minutes to remove any residual magnetism.
Description : Relative to the direction of rotation, a D.C. motor commutating pole has the same polarity as the _____________. A. main pole following B. interpole following C. main pole preceding D. interpole preceding
Last Answer : Answer: C
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 : To which polarity does a positive damper with positive bins clamp the most negative extremity of the output waveform (positive or negative)?
Last Answer : Positive potential.
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 : 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 : 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 the polarity of the first alternation of the tank circuit in an emitter-loaded npn pulsed oscillator?
Last Answer : Negative
Description : Using Weber’s molecular theory of magnetism, describe the polarity of the magnetic poles produced by stroking a magnetic material from right to left with the south pole of a magnet.
Last Answer : South pole at the right, north pole at the left.
Description : If logic 1 = -5 vdc and logic 0 = 0 vdc, what logic polarity is being used?
Last Answer : Negative.
Description : If logic 1 = +2 vdc and logic 0 = -2 vdc, what logic polarity is being used?
Description : If logic 1 = -5 vdc and logic 0 = -10 vdc, what logic polarity is being used?
Description : In applying Kirchhoff’s current law, what does the polarity of the current indicate?
Last Answer : Whether the current is entering the junction (+) or leaving the junction (-).
Description : What is the polarity of the currents that feed the V antenna?
Last Answer : Opposite.
Description : Cold-cathode tubes can be used as voltage regulators because of what characteristic?
Last Answer : They have the ability to maintain a constant voltage drop across the tube despite changes in current flow.
Description : What undesirable effect is caused by the inductance of the cathode lead?
Last Answer : Degenerative feedback.
Description : When a circuit uses cathode biasing, the input signal can cause varia
Last Answer : Through the use of a bypass capacitor
Description : What type of bias requires constant current flow through the cathode
Last Answer : Cathode biasing.
Description : What serves as the cathode of a dry cell?
Last Answer : The zinc container.
Description : What type of modulator is the cathode modulator (low- or high-level)?
Last Answer : Low-level.
Description : In a semiconductor diode, p-side is earthed and to n-side is applied a potential of -2 volt; the diode shall (a) Conduct (b) Not conduct (c) Conduct partially (d) Break down
Last Answer : a) Conduct
Description : Auditing standards require a successor auditor to communicate with the predecessor auditor. The Code of Professional Conduct requires confidentiality; therefore, the client's permission must be obtained ... since this is one of the exceptions to confidentiality in the Code of Professional Conduc
Last Answer : The successor auditor
Description : Because an external auditor is paid a fee by a client company, he a. Is absolutely independent and may conduct an audit. b. May be sufficiently independent to conduct an audit. c. Is ... to be independent. d. Must receive approval of the Securities and Exchange Commission before conducting an audit.
Last Answer : May be sufficiently independent to conduct an audit.
Description : When replacing component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its ... provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage
Description : Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range ... of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.
Description : You are using a mechanical voltage tester to check the fuses in a three-phase circuit supplying an electric motor. For which of the following reasons must the motor be stopped during the test? A. ... circuit would be indicated by the voltage tester with the circuit energized. D. All of the above.
Description : When measuring AC current flow, you must always connect the meter _____________. A. in series with the power source and load B. in parallel with the power source and load C. insuring correct polarity D. using the lowest range possible to prevent instrument damage
Description : In troubleshooting a circuit in a console, you find that a resistor may be faulty. Which of the precautions listed must be observed when using an ohmmeter to carry out this test? A. Correct polarity ... D. The resistor's circuit must be de-energized and at least one end of the component isolated.
Description : While troubleshooting a circuit in an engine room central control console, a resistor is suspected of being faulty. Which of the following precautions must be observed if an ohmmeter is to be used to ... of the component isolated. D. The meter case must be grounded prior to attaching the leads.
Description : When changing out component 'B' of the circuit shown in the illustration, it is important to know that ____________. EL-0081 A. it is polarity sensitive and must be inserted as indicated on its ... provide the capacitor's initial charge D. it must match the circuit voltage and component 'C' wattage
Description : When an SCR is forward biased, what is needed to cause it to conduct?
Last Answer : A gate signal.
Description : Does a rectifier tube conduct on the positive or negative alternation of the input signal?
Description : What term describes a device used to conduct heat away from a component?
Last Answer : A thermal shunt.
Description : When testing an SCR with an ohmmeter, the SCR will conduct if what two elements are shorted together?
Last Answer : Gate and anode.
Description : Which of the following statements comparing transistors and vacuum tubes is correct? A. Both transistors and vacuum tubes have a cathode that must be heated to give off electrons. B. A vacuum tube must ... flow. D. The anode of both transistors and vacuum tubes must be heated to give off electrons.
Description : What is the condition of the diode in a series limiter when an output is developed? In a parallel limiter?
Last Answer : Conducting, cutoff.
Description : In the tunnel diode, the tunneling current is at what level when the forbidden gap of the N-type material is at the same energy level as the empty states of the P-type material?
Last Answer : Minimum.
Description : Why is electron flow with the arrow in the symbol of a Zener diode instead of against the arrow as it is in a normal diode?
Last Answer : Because Zener diodes are operated in the reverse bias mode.
Description : During avalanche effect breakdown, what limits current flow through the diode?
Last Answer : an external current-limiting resistor
Description : What is the doping level of an avalanche effect diode when compared to the doping level of a Zener-effect diode?
Last Answer : The doping level of an avalanche effect diode is lower.
Description : What is the name of the simplest type of rectifier which uses one diode?
Last Answer : The half-wave rectifier.