1.
In a permanent magnet moving coil, the pointer is returned to its original position by ___________.
Correct Answer
A. The use of a hairspring.
Explanation
The pointer in a permanent magnet moving coil is returned to its original position by the use of a hairspring. A hairspring is a thin, coiled strip of metal that provides a restoring force to bring the pointer back to its starting position after it has been deflected. This ensures that the pointer always returns to zero when there is no current flowing through the coil.
2.
What type of meter uses the principle of magnetic repulsion between like poles?
Correct Answer
B. Moving-vane Meter Movement
Explanation
The moving-vane meter movement uses the principle of magnetic repulsion between like poles. In this type of meter, a vane is suspended between two magnets, and when a current flows through the coil, it creates a magnetic field that interacts with the magnetic field of the magnets. The like poles repel each other, causing the vane to move. By measuring the deflection of the vane, the current can be determined.
3.
An ammeter must never be connected ________ the power supply.
Correct Answer
B. In parallel with
Explanation
An ammeter must never be connected in parallel with the power supply because it will result in a short circuit. Connecting the ammeter in parallel would create a low-resistance path for the current to bypass the intended circuit, causing an excessive current flow that could damage the ammeter and potentially other components in the circuit. Therefore, it is important to always connect the ammeter in series with the circuit to accurately measure the current flowing through it.
4.
If the range of current to be measured is greater than the full scale current of the meter, a __________ must be installed in ____________ with the meter.
Correct Answer
C. Shunt resistor, parallel
Explanation
If the range of current to be measured is greater than the full scale current of the meter, a shunt resistor must be installed in parallel with the meter. This is because a shunt resistor provides an alternate path for the excess current to flow, allowing only the desired current to pass through the meter. Installing the shunt resistor in parallel ensures that the current is divided between the meter and the shunt resistor, allowing accurate measurement of the higher current range.
5.
What device works on effect of sensed DC magnetic field on a self transmitted AC magnetic field to measure current flow?
Correct Answer
C. Current Transformer
Explanation
A current transformer is a device that works on the effect of sensed DC magnetic field on a self-transmitted AC magnetic field to measure current flow. It consists of a primary winding that carries the current to be measured and a secondary winding that is connected to a measuring instrument. The current flowing through the primary winding creates a magnetic field, which induces a proportional current in the secondary winding. This secondary current can then be measured to determine the magnitude of the primary current.
6.
Which device is categorized by 50:5, 100:5, 300:5, etc. as ratio of the current between the conductor and the meter reading?
Correct Answer
A. Current transformer
Explanation
A current transformer is a device that is categorized by ratios such as 50:5, 100:5, 300:5, etc. These ratios represent the relationship between the current flowing through the conductor and the current measured by the meter. Current transformers are commonly used in electrical systems to step down high currents to a level that can be safely measured by ammeters or other measuring devices. They are designed to provide accurate and proportional current measurements, making them an essential component in various applications, including power distribution systems and electrical equipment monitoring.
7.
What type of meter is used to measure the pressure being applied to the circuit?
Correct Answer
C. Voltmeter
Explanation
A voltmeter is used to measure the voltage, or potential difference, across a circuit. In this context, the pressure being applied to the circuit refers to the voltage. Therefore, a voltmeter is the appropriate meter to measure the pressure being applied to the circuit.
8.
To measure voltage in a circuit, the voltmeter should be connected in ________.
Correct Answer
B. Parallel
Explanation
To measure voltage in a circuit, the voltmeter should be connected in parallel. This is because connecting the voltmeter in parallel allows it to measure the potential difference across a specific component or set of components in the circuit. If the voltmeter were connected in series, it would disrupt the circuit and affect the voltage being measured. Therefore, connecting the voltmeter in parallel ensures accurate measurements of voltage without interfering with the circuit's operation.
9.
What will happen if an analog voltmeter is reverse connected into an energized circuit?
Correct Answer
C. The needle might be damaged.
Explanation
If the voltmeter is reverse connected into an energized circuit, the needle might be damaged. When the voltmeter is connected in reverse, it will measure the voltage in the opposite direction. This can cause the needle to move beyond its maximum range, potentially causing damage to the needle or the internal components of the voltmeter.
10.
What device is connected to the d'Arsonval meter to allow measurement of AC current?
Correct Answer
B. Rectifier
Explanation
A rectifier is a device that converts alternating current (AC) to direct current (DC). In the context of the d'Arsonval meter, which is a type of analog meter used to measure current, a rectifier is necessary to convert the AC current being measured into DC current. This allows the meter to accurately measure the magnitude of the current flowing through the circuit. Therefore, a rectifier is connected to the d'Arsonval meter to enable the measurement of AC current.
11.
What is the process of "smoothing-out" the oscillation of the pointer in the d'Arsonval meter?
Correct Answer
B. Damping
Explanation
Damping is the process of reducing or eliminating the oscillation of the pointer in a d'Arsonval meter. It involves adding a damping mechanism such as a fluid or magnetic system that provides resistance to the movement of the pointer. This resistance helps to slow down the movement of the pointer, preventing it from oscillating rapidly and allowing for more accurate readings.
12.
Which method is used in damping othe vibrations due to rectifiers in an d'Arsonval meter?
Correct Answer
C. By the induced magnetic field in the coil.
Explanation
All answers are correct.
13.
Which device is commonly known as of an electrodynamic type?
Correct Answer
C. Wattmeter
Explanation
A wattmeter is commonly known as an electrodynamic type device. This is because it uses the principle of electromagnetic induction to measure the power or energy consumption in an electrical circuit. It measures the product of voltage and current, which is power, and displays it in watts. The device consists of a current coil and a potential coil, both of which are connected to the circuit being measured. The interaction between the magnetic fields produced by these coils and the current flowing through the circuit allows the wattmeter to accurately measure power.
14.
A wattmeter is rated in ______.
Correct Answer
B. Volts
Explanation
Volts and Amperes; not Watts
15.
When using an ohmmeter, the needle pointer will deflect to what direction if it reads high resistance?
Correct Answer
C. Will not move.
Explanation
When using an ohmmeter, the needle pointer will not move if it reads high resistance. This is because high resistance indicates a lack of continuity in the circuit, meaning that there is little to no current flowing through it. As a result, the needle pointer remains stationary, indicating that there is no path for the current to flow and complete the circuit.
16.
What is the purpose of the mirror on the scale of an analogue meter?
Correct Answer
A. To remove parallax error.
Explanation
The purpose of the mirror on the scale of an analogue meter is to remove parallax error. Parallax error occurs when the observer's line of sight is not directly perpendicular to the scale, causing the pointer to appear at a different position than it actually is. By using a mirror, the observer can align their line of sight with the reflection of the pointer, eliminating parallax error and allowing for more accurate readings.
17.
Which of the following is true about an ohmmeter?
Correct Answer
B. Full scale deflection reads minimum resistance.
Explanation
An ohmmeter is a device used to measure electrical resistance. When using an ohmmeter, it should be connected in series with the component or circuit being measured. The full scale deflection of an ohmmeter occurs when the resistance being measured is at its minimum value. This means that when the needle of the ohmmeter reaches the maximum position on the scale, it indicates that the resistance being measured is at its lowest possible value. Therefore, the statement "Full scale deflection reads minimum resistance" is true about an ohmmeter.
18.
An ohmmeter with sensitivity of 10,000 per volt means that
Correct Answer
A. 1000 ohms resistance is needed to 1 milliamp of current at FSD
Explanation
An ohmmeter with a sensitivity of 10,000 per volt means that for every volt applied, the ohmmeter will read 10,000 ohms. Therefore, if 1 milliamp of current is applied at full scale deflection (FSD), the ohmmeter will read 10,000 ohms. So, 1000 ohms resistance is needed to produce 1 milliamp of current at FSD.
19.
What device is used to measure the resistance of the insulation while subjecting it to a high voltage?
Correct Answer
C. Megger
Explanation
A Megger is a device that is specifically designed to measure the resistance of insulation while subjecting it to a high voltage. It is commonly used in electrical testing and maintenance to ensure the integrity of insulation in various electrical systems and equipment. The device applies a high voltage to the insulation and measures the resulting current flow, allowing technicians to assess the quality and effectiveness of the insulation. Therefore, the Megger is the correct device for measuring insulation resistance under high voltage conditions.
20.
When testing for insulation resistance, it is necessary to test at a voltage approximately
Correct Answer
A. 1.5 times the operating voltage
Explanation
When testing for insulation resistance, it is necessary to test at a voltage approximately 1.5 times the operating voltage. This is because testing at a higher voltage helps to ensure that the insulation can withstand the normal operating voltage without any breakdown or failure. By testing at a higher voltage, any potential weak points or defects in the insulation can be identified and addressed before they cause any issues during normal operation. Therefore, testing at 1.5 times the operating voltage provides a margin of safety and helps to ensure the reliability and performance of the insulation.
21.
What device is a low reading ohmmeter and measures resistance in milliohms that tests the bonding of aircraft components and structure?
Correct Answer
C. Bonding Meter
Explanation
A bonding meter is a device specifically designed to measure resistance in milliohms, making it a low reading ohmmeter. It is used to test the bonding of aircraft components and structures, ensuring that they are properly connected and grounded for safety purposes. The other options, Safety Ohmmeter and Milliohmmeter, do not specifically mention testing bonding in aircraft components and structure, making them less suitable for this specific application.
22.
Which device are specifically designed for ultra safe resistance on explosive devices and in hazardous environments?
Correct Answer
B. Safety Ohmmeter
Explanation
Safety Ohmmeters are specifically designed for ultra-safe resistance measurements on explosive devices and in hazardous environments. These devices are built with robust safety features to ensure that they can be used in potentially dangerous situations without causing any harm. They are often used in industries such as mining, oil and gas, and chemical plants, where there is a high risk of explosions or other hazardous conditions. Safety Ohmmeters are essential tools for maintaining safety standards and preventing accidents in these environments.
23.
If the arrow is toward the load, a RF Directional Wattmeter is measuring the
Correct Answer
A. Forward Power
Explanation
A RF Directional Wattmeter measures the power flowing in the forward direction. When the arrow is toward the load, it indicates that the power is flowing from the source to the load. Therefore, the RF Directional Wattmeter is measuring the Forward Power.
24.
What device is used to measure forward and reflected power of RF radio devices?
Correct Answer
B. RF Directional Wattmeter
Explanation
An RF Directional Wattmeter is used to measure both forward and reflected power of RF radio devices. This device is designed to measure the power flow in a specific direction, allowing users to accurately measure the power being transmitted by the device as well as any power that is being reflected back. It is commonly used in RF and microwave systems to ensure the efficiency and performance of the radio devices. The other options, Time Domain Reflectometer and ATC/DME Meter, are not specifically designed for measuring forward and reflected power in RF radio devices.
25.
What device is used to determine the digital state of an electronic circuit?
Correct Answer
C. Logic Probe
Explanation
A logic probe is a device used to determine the digital state of an electronic circuit. It is commonly used by technicians and engineers to troubleshoot and test digital circuits. The logic probe detects and indicates whether a voltage level is high (logic 1) or low (logic 0) in the circuit being tested. It is a simple and convenient tool for checking the logic levels and diagnosing problems in digital circuits.
26.
What device is used to determine the shape of a video pulse or signal appearing at a selected test points?
Correct Answer
C. Oscilloscope
Explanation
An oscilloscope is a device used to determine the shape of a video pulse or signal appearing at a selected test point. It is a tool that displays voltage signals as a two-dimensional graph, allowing users to analyze and measure various electrical waveforms. Oscilloscopes are commonly used in electronics, telecommunications, and engineering fields to troubleshoot and diagnose problems in circuits and signals. They provide visual representations of waveforms, helping technicians and engineers understand the characteristics of the signal and identify any abnormalities or distortions.
27.
Using an oscillosope, the voltage at selected test point is measured as 100V. What is the equivalent RMS voltage?
Correct Answer
C. 70V
Explanation
The question asks for the equivalent RMS voltage when the voltage at the selected test point is measured as 100V using an oscilloscope. The RMS voltage is the root mean square value of the voltage, which represents the effective voltage. Since the question does not provide any additional information or context, it can be assumed that the equivalent RMS voltage is the same as the measured voltage, which is 100V. Therefore, the correct answer is 70V.
28.
What device is used to attenuate a signal without distorting the waveform?
Correct Answer
B. Attenuator
Explanation
An attenuator is a device used to reduce the amplitude of a signal without distorting its waveform. It is commonly used in audio and telecommunications systems to control signal levels and prevent overloading of downstream components. Unlike an amplifier, which increases the signal strength, an attenuator decreases the signal power while maintaining the shape and characteristics of the original waveform. This allows for precise control and adjustment of signal levels without introducing any distortion or unwanted artifacts. Therefore, an attenuator is the correct device for attenuating a signal without distorting the waveform.
29.
Before using an attenuator probe, you must
Correct Answer
A. Adjust the compensating capacitor
Explanation
When using an attenuator probe, it is necessary to adjust the compensating capacitor. This is because the compensating capacitor helps to maintain the accuracy of the measurement by compensating for any capacitance introduced by the probe. By adjusting the compensating capacitor, the probe can be properly calibrated and the measurements obtained on the oscilloscope will be accurate. Adjusting the voltage shown in the oscilloscope or the output of a signal generator are not relevant steps when using an attenuator probe.
30.
What device is used in analyzing the magnitude and shape of reflected waveform in a coaxial signals?
Correct Answer
B. Time Domain Reflectometer
Explanation
A Time Domain Reflectometer (TDR) is a device used to analyze the magnitude and shape of reflected waveforms in coaxial signals. It sends a pulse down the coaxial cable and measures the time it takes for the pulse to return after being reflected by any impedance mismatches or faults in the cable. By analyzing the time and amplitude of the reflected waveform, the TDR can determine the location and severity of any issues in the coaxial cable. Therefore, the TDR is the correct device for analyzing the magnitude and shape of reflected waveforms in coaxial signals.
31.
What device is used to subtitute loads in an electrical system?
Correct Answer
B. Decade Boxes
Explanation
Decade boxes are devices used to substitute loads in an electrical system. They allow the user to manually adjust the resistance, capacitance, or inductance to simulate different loads. This is useful for testing and troubleshooting electrical circuits without the need for actual loads. Attenuators are used to reduce the amplitude of a signal, while capacitors store and release electrical energy. Therefore, the correct answer is decade boxes.
32.
What device is used to generate alternating current of desired frequencies and amplitudes?
Correct Answer
B. Signal Generator
Explanation
A signal generator is a device used to produce electrical signals of desired frequencies and amplitudes. It is commonly used in various applications such as testing and troubleshooting electronic circuits, calibrating equipment, and generating signals for research purposes. Unlike an oscilloscope, which is used to visualize and measure electrical waveforms, a signal generator is specifically designed to generate electrical signals. A time domain reflectometer, on the other hand, is used for measuring the length and impedance of transmission lines. Therefore, the correct answer is Signal Generator.
33.
What device is used to regulate the voltage output in a signal generator?
Correct Answer
C. Attenuator
Explanation
An attenuator is a device used to reduce the amplitude or power of a signal without significantly distorting its waveform. In the context of a signal generator, an attenuator is used to regulate the voltage output by attenuating or reducing the signal strength to a desired level. This helps in controlling the voltage output accurately and ensuring that the generated signal matches the required specifications. Amplifiers, on the other hand, are used to increase the amplitude of a signal, while a decade box is a device used for precise resistance or capacitance measurements, not voltage regulation.
34.
A signal generator used for testing LOC, G/S, VOR, MKR and communication systems is called ________.
Correct Answer
B. Nav-Comm Ramp Tester
Explanation
A signal generator used for testing LOC, G/S, VOR, MKR, and communication systems is called a Nav-Comm Ramp Tester. This device is specifically designed to test and simulate signals for navigation (LOC, G/S, VOR) and communication systems. It is used to ensure the proper functioning and accuracy of these systems during testing and maintenance procedures. The Nav-Comm Ramp Tester provides a comprehensive solution for testing multiple systems in one device, making it an essential tool for aviation professionals.
35.
What device interrogates the ATC transponder and tests the validity of the returned signal?
Correct Answer
B. ATC Transponder Test Set
Explanation
ATC Transponder Test Set and DME Tester are both correct.
36.
What device is used for testing altitude and airspeed indications?
Correct Answer
A. Pitot-Static Test Set
Explanation
A Pitot-Static Test Set is used for testing altitude and airspeed indications. This device is specifically designed to measure and calibrate the Pitot and Static systems of an aircraft. The Pitot system measures the dynamic pressure of the airspeed, while the Static system measures the static pressure for altitude indication. By using a Pitot-Static Test Set, technicians can ensure that the aircraft's altitude and airspeed instruments are accurately calibrated and functioning properly.
37.
What device is capable of measuring system lead resistance, insulation, and performing indicator run-outs of a temperature measuring system?
Correct Answer
B. Digital Turbine Temperature Tester
Explanation
A digital turbine temperature tester is capable of measuring system lead resistance, insulation, and performing indicator run-outs of a temperature measuring system. This device is specifically designed to test and analyze the temperature measurement system in turbines, ensuring accurate and reliable readings. It can assess the resistance of the system's leads, check for any insulation issues, and evaluate the performance of the temperature indicators. This tester is a valuable tool for maintaining the efficiency and functionality of temperature measuring systems in various applications.
38.
Fuel Quantity Indication Tester works in the principle of
Correct Answer
C. Capacitance
Explanation
The Fuel Quantity Indication Tester works based on the principle of capacitance. Capacitance is the ability of a system to store an electric charge. In this case, the tester measures the capacitance of the fuel quantity indication system to determine the amount of fuel present. This is done by measuring the change in capacitance as the fuel level changes. By using capacitance, the tester can accurately indicate the quantity of fuel in the tank.
39.
The method of connecting conductors using a crimped connector is called ________.
Correct Answer
B. Splicing
Explanation
The method of connecting conductors using a crimped connector is called splicing. Splicing involves joining two or more conductors together by stripping the insulation from the ends, twisting them together, and securing them with a crimped connector. This method ensures a secure and reliable electrical connection. Soldering, on the other hand, involves melting solder onto the conductors to create a permanent bond, while crimping refers to the act of compressing a connector onto the conductors to create a mechanical connection.
40.
Which of the following is a temporary splice type?
Correct Answer
C. Knife splice
Explanation
A knife splice is a temporary splice type used to join two wires together. It involves stripping the insulation from the ends of the wires, overlapping them, and then wrapping them tightly with electrical tape. This type of splice is typically used when a permanent connection is not required, such as during testing or troubleshooting. It can easily be undone by removing the tape and separating the wires, making it a temporary solution. Butt splice and ring terminal, on the other hand, are permanent splice types used for secure and long-lasting connections.
41.
Identify the type of splice shown.
Correct Answer
C. Butt splice
Explanation
The correct answer is "Butt splice". A butt splice is a type of electrical connection where two wires are joined end-to-end by aligning the ends and securing them together. This type of splice is commonly used when extending or repairing wires, as it provides a secure and reliable connection. It is made by stripping the insulation from the wire ends, overlapping them, and then soldering or crimping them together. The resulting connection is strong and maintains the electrical continuity between the wires.
42.
What is the purpose of this knob?
Correct Answer
C. To adjust the needle for calibration.
Explanation
The purpose of the knob is to adjust the needle for calibration. This suggests that the knob is used to align the needle with the correct measurement or reference point, ensuring the accuracy of the meter. By adjusting the needle, the user can calibrate the meter to provide precise readings.
43.
What type of meter is shown?
Correct Answer
B. Permanent magnet moving-coil movement
Explanation
The correct answer is "Permanent magnet moving-coil movement." This type of meter movement uses a permanent magnet to create a magnetic field, which interacts with a coil of wire that moves when current flows through it. The movement of the coil is proportional to the current being measured, allowing the meter to display the current value. This type of meter is commonly used in ammeters and voltmeters.
44.
What type of equipment is used to check the resistanse of fire extinguisher squib of aircraft fire extinguishing system?
Correct Answer
B. Safety Ohmmeter
Explanation
A safety ohmmeter is used to check the resistance of a fire extinguisher squib in an aircraft fire extinguishing system. This type of equipment is specifically designed to measure electrical resistance in a safe and controlled manner. It ensures that the squib is functioning properly and has the correct resistance within the system. This is important for the overall safety and effectiveness of the fire extinguishing system in an aircraft.
45.
Crimp types for 22-18 AWG size is identified with what color code?
Correct Answer
A. Red
Explanation
The crimp types for 22-18 AWG size are identified with the color code red. This means that when working with wires of this size, crimps or connectors with a red color code should be used. The color coding system helps to ensure that the correct crimp type is selected for the specific wire size, allowing for a secure and reliable connection.
46.
What is the purpose of partially filling the terminal with anti-oxidant paste?
Correct Answer
B. To seal it.
Explanation
The purpose of partially filling the terminal with anti-oxidant paste is to seal it. This paste helps to protect the terminal from moisture, dirt, and other contaminants that can cause corrosion. By creating a barrier, the paste prevents these elements from entering the terminal and causing damage. Sealing the terminal also helps to ensure a secure and stable electrical connection, as it prevents any loose or weak connections that may occur due to corrosion.
47.
Identify the defect with this crimped terminal.
Correct Answer
C. Incorrect crimping lug
Explanation
The given answer states that the defect with the crimped terminal is an incorrect crimping lug. This means that the lug used for crimping is not the appropriate or correct one for this specific terminal. This could lead to a faulty connection or improper functioning of the terminal.
48.
Identify the problem in the crimped ring terminal.
Correct Answer
B. Conductors are not crimped.
Explanation
The problem in the crimped ring terminal is that the conductors are not properly crimped. This means that the conductors are not securely attached to the terminal, which can lead to a poor electrical connection and potential failure. Crimping is a process of compressing the metal terminal around the wire, creating a strong and reliable connection. If the conductors are not crimped, it is likely that they are loose or can easily detach from the terminal, causing issues with the electrical circuit.
49.
Which side is used for removal of contacts?
Correct Answer
B. White
Explanation
The explanation for the correct answer is that the white side is used for the removal of contacts. This implies that the red side is not used for contact removal, and both sides cannot be used for removal.
50.
What is the purpose of a loom comb?
Correct Answer
B. To ensure wires lies parallel to each other.
Explanation
All answers are correct.