Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
ATT COMP: Electronics & Electrical Systems (2026)aviation electronics (Avionics)
Typology: Exams
1 / 12
This page cannot be seen from the preview
Don't miss anything!
Table of Contents
1. AC Waveforms & Oscilloscope Measurements How do you find Peak voltage ($V_p$)? $V_{pp} \times 0.707$ $V_{pp} \div 2$ $V_{rms} \times 1.414$ $V_p \times 2$ Vpp ÷ 2 How do you find $V_{rms}$? $0.707 \times V_p$ $1.414 \times V_p$ $V_{pp} \div 2$ $V_p \times 0.5$ 0.707 X Vp Which quantity cannot be measured directly or derived from an oscilloscope? Voltage Frequency Period Resistance resistance What value of AC voltage does an oscilloscope directly measure? Average Voltage RMS Voltage Peak-to-Peak
Increased secondary voltage No current in the secondary High current in the primary Secondary short circuit produces no current in the secondary A partial short in the primary of a transformer will: Decrease secondary voltage Increase secondary voltage Eliminate secondary voltage Have no effect increase is secondary voltage Which part of a power supply unit changes pulsating DC to smooth DC? The Rectifier The Regulator The Filter The Transformer the filter What part of a power supply unit changes AC to pulsating DC? The Regulator The Rectifier The Filter The Capacitor the rectifier
What section of a power supply unit maintains a constant output voltage? The Filter The Rectifier The Transformer The Regulator the regulator
3. Circuit Troubleshooting & Fault Analysis Which troubleshooting step is used to localize a problem? Visual Inspection Operational Check Calculate and Measure Repair and Verify calculate and measure If you measure a component voltage equal to the applied voltage, it is: Shorted Operational Open Grounded open An open component or wire will measure: Minimum resistance
Step 2 Step 3 Step 4 step four
4. Relays & Maintenance Current flowing through a relay's contacts in only one direction can cause what specific failure? Overheating Coned and cratered contacts Coil burnout Armature sticking coned and cratered contacts How do you clean relay contacts? A wire brush A burnishing tool Compressed air Sandpaper a burnishing tool How do you fix a sealed relay? Open and clean the contacts Replace the coil only Replace the entire relay Lubricate the armature replace the entire relay
5. Frequency, Period, & Wavelength Formulas What is the formula for finding the period ($T$) of a wavelength? $T = f \times 2$ $T = 1 \div f$ $T = V \div R$ $T = \lambda \div f$ T= 1÷f What is the period of a 20 Hertz sine wave? 0.01 seconds 0.05 seconds 0.5 seconds 50 milliseconds 0.05 seconds How do you find wavelength ($\lambda$)? $\lambda = f \div 300 \times 10^6$ $\lambda = 300 \times 10^6 \div f$ $\lambda = T \times f$ $\lambda = 1 \div f$ Lambda = 300 X 10^6 ÷ f What is the wavelength of a 20 kilohertz sine wave? 1,500 meters 15,000 meters 150 meters
16 Milli 16 Mega 16 Giga 16 Mega What is the metric prefix for 0.000006? 6 milli 6 micro 6 nano 6 pico 6 micro
7. Electrical Safety & Protection What is the minimum AC current normally required to cause severe muscular contractions? 1 milliamp 12 milliamps 100 milliamps 5 milliamps 12 milliamps What should you do first if someone has been shocked? Start CPR Call 911 Remove the victim from the source Check for a pulse remove the victim from the source
Which category includes electrical fires? Class A Class B Class C Class D Class C Are capacitors considered circuit protection devices? Yes No no
8. Cooling & Specialized Systems What component changes color to indicate an element change is needed in dry air systems? Desiccant bags Telltale oil filters Sight glass Humidity sensor Telltale oil filters What type of cooling is used in sealed enclosures? Liquid-to-Air Air-to-Air Convection only Immersion cooling air-to-air
