ATT TEST 7 EXAM LATEST 2024 ACTUAL EXAM 150
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
When Q1 is ON, what causes it to turn OFF? (monostable) - ANSWER-
C1 charges enough to turn Q2 ON which turns Q1 off
How is frequency determined in bistable multivibes? - ANSWER-
Output frequency is 1/2 Input frequency
If Q1 conducts first (ON 0V), how is Q2 turned OFF? (bistable) -
ANSWER-Negative volts on Q2 base coupled through capacitor
With Q1 ON, how is Q1 turned OFF? (Bistable) - ANSWER-Negative
pulse from INPUT forward biases D1, negative signal turns Q1 OFF
With Q1 OFF, how is Q2 turned ON? (Bistable) - ANSWER-!2V on Q1
collector coupled to Q2 base by capacitor
What is troubleshooting procedure for astable multivibes? - ANSWER-
Check output, Vcc, transistors, resistance checks
What is troubleshooting procedure for monostable/bistable multivibes? -
ANSWER-Check output, input trigger, Vcc, transistors, resistances
What is the purpose of a schmitt trigger? - ANSWER-Convert ANY
shape waveform into square wave pulses of CONSTANT amplitude
, ATT TEST 7 EXAM LATEST 2024 ACTUAL EXAM 150
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
Schmitt trigger is also called what other names? - ANSWER-Squaring
amp, level detector, threshold detector
What determines upper threshold in schmitt trigger? - ANSWER-
Voltage divider
What happens when upper threshold is reached? - ANSWER-Q1
approaches saturation (ON) and drives Q2 into cutoff (high output)
What ensures very short rise/fall times in schmitt trigger? - ANSWER-
Feedback circuit
What turns Q2 on in schmitt trigger? - ANSWER-Vcc
How is low output formed schmitt trigger? - ANSWER-Volt divider
formed between R6 and R8, 0V on Q2 collector causes low voltage
drops
What is frequency range of AM? - ANSWER-535kHz to 1605 kHz
Voice, music, coded signals are all types of what? - ANSWER-
Intelligence (Information)
, ATT TEST 7 EXAM LATEST 2024 ACTUAL EXAM 150
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
What is modulation? - ANSWER-The process of superimposing
waveform onto RF carrier (low frequency audio signal on high
frequency carrier)
What is a benefit of modulation? - ANSWER-Reduces necessity for
long antennas
What is demodulation? - ANSWER-Process of extracting intelligence
from carrier frequency
What is noise? - ANSWER-Any unwanted disruption/variation that
contaminates modulated carrier
What are three types of noise? - ANSWER-Man-made, atmospheric,
galactic
What is distortion? - ANSWER-Degradation of signal, commonly
resulting from overdriven amps. Clipped or flattened peaks
What is selectivity? - ANSWER-Receivers ability to tune to specific
frequency and reject unwanted frequencies
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
When Q1 is ON, what causes it to turn OFF? (monostable) - ANSWER-
C1 charges enough to turn Q2 ON which turns Q1 off
How is frequency determined in bistable multivibes? - ANSWER-
Output frequency is 1/2 Input frequency
If Q1 conducts first (ON 0V), how is Q2 turned OFF? (bistable) -
ANSWER-Negative volts on Q2 base coupled through capacitor
With Q1 ON, how is Q1 turned OFF? (Bistable) - ANSWER-Negative
pulse from INPUT forward biases D1, negative signal turns Q1 OFF
With Q1 OFF, how is Q2 turned ON? (Bistable) - ANSWER-!2V on Q1
collector coupled to Q2 base by capacitor
What is troubleshooting procedure for astable multivibes? - ANSWER-
Check output, Vcc, transistors, resistance checks
What is troubleshooting procedure for monostable/bistable multivibes? -
ANSWER-Check output, input trigger, Vcc, transistors, resistances
What is the purpose of a schmitt trigger? - ANSWER-Convert ANY
shape waveform into square wave pulses of CONSTANT amplitude
, ATT TEST 7 EXAM LATEST 2024 ACTUAL EXAM 150
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
Schmitt trigger is also called what other names? - ANSWER-Squaring
amp, level detector, threshold detector
What determines upper threshold in schmitt trigger? - ANSWER-
Voltage divider
What happens when upper threshold is reached? - ANSWER-Q1
approaches saturation (ON) and drives Q2 into cutoff (high output)
What ensures very short rise/fall times in schmitt trigger? - ANSWER-
Feedback circuit
What turns Q2 on in schmitt trigger? - ANSWER-Vcc
How is low output formed schmitt trigger? - ANSWER-Volt divider
formed between R6 and R8, 0V on Q2 collector causes low voltage
drops
What is frequency range of AM? - ANSWER-535kHz to 1605 kHz
Voice, music, coded signals are all types of what? - ANSWER-
Intelligence (Information)
, ATT TEST 7 EXAM LATEST 2024 ACTUAL EXAM 150
QUESTIONS AND CORRECT DETAILED (VERIFIED
ANSWERS) |ALREADY GRADED A
What is modulation? - ANSWER-The process of superimposing
waveform onto RF carrier (low frequency audio signal on high
frequency carrier)
What is a benefit of modulation? - ANSWER-Reduces necessity for
long antennas
What is demodulation? - ANSWER-Process of extracting intelligence
from carrier frequency
What is noise? - ANSWER-Any unwanted disruption/variation that
contaminates modulated carrier
What are three types of noise? - ANSWER-Man-made, atmospheric,
galactic
What is distortion? - ANSWER-Degradation of signal, commonly
resulting from overdriven amps. Clipped or flattened peaks
What is selectivity? - ANSWER-Receivers ability to tune to specific
frequency and reject unwanted frequencies
