Initial checkin
This commit is contained in:
Chris
99
logseq/bak/pages/E4E/2025-05-01T20_36_29.891Z.Desktop.md
Normal file
99
logseq/bak/pages/E4E/2025-05-01T20_36_29.891Z.Desktop.md
Normal file
@ -0,0 +1,99 @@
|
||||
E4E Noise and interference: external RF interference; electrical and computer noise; line noise; DSP filtering and noise reduction; common-mode current; surge protectors; single point ground panel
|
||||
|
||||
- [[E4E01]] (A)
|
||||
What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals?
|
||||
- [[A.]] Removal of the CW signal as well as the interfering carrier
|
||||
- [[B.]] Any nearby signal passing through the DSP system will overwhelm the desired signal
|
||||
- [[C.]] Excessive ringing
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E02]] (D)
|
||||
Which of the following types of noise can often be reduced by a digital noise reduction?
|
||||
- [[A.]] Broadband white noise
|
||||
- [[B.]] Ignition noise
|
||||
- [[C.]] Power line noise
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E03]] (B)
|
||||
Which of the following types of noise are removed by a noise blanker?
|
||||
- [[A.]] Broadband white noise
|
||||
- [[B.]] Impulse noise
|
||||
- [[C.]] Hum and buzz
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E04]] (D)
|
||||
How can conducted noise from an automobile battery charging system be suppressed?
|
||||
- [[A.]] By installing filter capacitors in series with the alternator leads
|
||||
- [[B.]] By installing a noise suppression resistor and a blocking capacitor at the battery
|
||||
- [[C.]] By installing a high-pass filter in series with the radio’s power lead and a low-pass filter in parallel with the antenna feed line
|
||||
- [[D.]] By installing ferrite chokes on the charging system leads
|
||||
--
|
||||
- [[E4E05]] (B)
|
||||
What is used to suppress radio frequency interference from a line-driven AC motor?
|
||||
- [[A.]] A high-pass filter in series with the motor’s power leads
|
||||
- [[B.]] A brute-force AC-line filter in series with the motor’s power leads
|
||||
- [[C.]] A bypass capacitor in series with the motor’s field winding
|
||||
- [[D.]] A bypass choke in parallel with the motor’s field winding
|
||||
--
|
||||
- [[E4E06]] (C)
|
||||
What type of electrical interference can be caused by computer network equipment?
|
||||
- [[A.]] A loud AC hum in the audio output of your station’s receiver
|
||||
- [[B.]] A clicking noise at intervals of a few seconds
|
||||
- [[C.]] The appearance of unstable modulated or unmodulated signals at specific frequencies
|
||||
- [[D.]] A whining-type noise that continually pulses off and on
|
||||
--
|
||||
- [[E4E07]] (B)
|
||||
Which of the following can cause shielded cables to radiate or receive interference?
|
||||
- [[A.]] Low inductance ground connections at both ends of the shield
|
||||
- [[B.]] Common-mode currents on the shield and conductors
|
||||
- [[C.]] Use of braided shielding material
|
||||
- [[D.]] Tying all ground connections to a common point resulting in differential-mode currents in the shield
|
||||
--
|
||||
- [[E4E08]] (B)
|
||||
What current flows equally on all conductors of an unshielded multiconductor cable?
|
||||
- [[A.]] Differential-mode current
|
||||
- [[B.]] Common-mode current
|
||||
- [[C.]] Reactive current only
|
||||
- [[D.]] Magnetically-coupled current only
|
||||
--
|
||||
- [[E4E09]] (C)
|
||||
What undesirable effect can occur when using a noise blanker?
|
||||
- [[A.]] Received audio in the speech range might have an echo effect
|
||||
- [[B.]] The audio frequency bandwidth of the received signal might be compressed
|
||||
- [[C.]] Strong signals may be distorted and appear to cause spurious emissions
|
||||
- [[D.]] FM signals can no longer be demodulated
|
||||
--
|
||||
- [[E4E10]] (D)
|
||||
Which of the following can create intermittent loud roaring or buzzing AC line interference?
|
||||
- [[A.]] Arcing contacts in a thermostatically controlled device
|
||||
- [[B.]] A defective doorbell or doorbell transformer inside a nearby residence
|
||||
- [[C.]] A malfunctioning illuminated advertising display
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E11]] (B)
|
||||
What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands?
|
||||
- [[A.]] One or more of the broadcast stations is transmitting an over-modulated signal
|
||||
- [[B.]] Nearby corroded metal connections are mixing and reradiating the broadcast signals
|
||||
- [[C.]] You are receiving skywave signals from a distant station
|
||||
- [[D.]] Your station receiver IF amplifier stage is overloaded
|
||||
--
|
||||
- [[E4E12]] (A)
|
||||
What causes interference received as a series of carriers at regular intervals across a wide frequency range?
|
||||
- [[A.]] Switch-mode power supplies
|
||||
- [[B.]] Radar transmitters
|
||||
- [[C.]] Wireless security camera transmitters
|
||||
- [[D.]] Electric fences
|
||||
--
|
||||
- [[E4E13]] (C)
|
||||
Where should a station AC surge protector be installed?
|
||||
- [[A.]] At the AC service panel
|
||||
- [[B.]] At an AC outlet
|
||||
- [[C.]] On the single point ground panel
|
||||
- [[D.]] On a ground rod outside the station
|
||||
--
|
||||
- [[E4E14]] (D)
|
||||
What is the purpose of a single point ground panel?
|
||||
- [[A.]] Remove AC power in case of a short-circuit
|
||||
- [[B.]] Prevent common-mode transients in multi-wire systems
|
||||
- [[C.]] Eliminate air gaps between protected and non-protected circuits
|
||||
- [[D.]] Ensure all lightning protectors activate at the same time
|
||||
99
logseq/bak/pages/E4E/2025-05-01T20_36_51.622Z.Desktop.md
Normal file
99
logseq/bak/pages/E4E/2025-05-01T20_36_51.622Z.Desktop.md
Normal file
@ -0,0 +1,99 @@
|
||||
E4E Noise and interference: external RF interference; electrical and computer noise; line noise; DSP filtering and noise reduction; common-mode current; surge protectors; single point ground panel
|
||||
|
||||
- [[E4E01]] (A)
|
||||
What problem can occur when using an automatic notch filter (ANF) to remove interfering carriers while receiving CW signals? #card
|
||||
- [[A.]] Removal of the CW signal as well as the interfering carrier
|
||||
- [[B.]] Any nearby signal passing through the DSP system will overwhelm the desired signal
|
||||
- [[C.]] Excessive ringing
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E02]] (D)
|
||||
Which of the following types of noise can often be reduced by a digital noise reduction? #card
|
||||
- [[A.]] Broadband white noise
|
||||
- [[B.]] Ignition noise
|
||||
- [[C.]] Power line noise
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E03]] (B)
|
||||
Which of the following types of noise are removed by a noise blanker? #card
|
||||
- [[A.]] Broadband white noise
|
||||
- [[B.]] Impulse noise
|
||||
- [[C.]] Hum and buzz
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E04]] (D)
|
||||
How can conducted noise from an automobile battery charging system be suppressed? #card
|
||||
- [[A.]] By installing filter capacitors in series with the alternator leads
|
||||
- [[B.]] By installing a noise suppression resistor and a blocking capacitor at the battery
|
||||
- [[C.]] By installing a high-pass filter in series with the radio’s power lead and a low-pass filter in parallel with the antenna feed line
|
||||
- [[D.]] By installing ferrite chokes on the charging system leads
|
||||
--
|
||||
- [[E4E05]] (B)
|
||||
What is used to suppress radio frequency interference from a line-driven AC motor? #card
|
||||
- [[A.]] A high-pass filter in series with the motor’s power leads
|
||||
- [[B.]] A brute-force AC-line filter in series with the motor’s power leads
|
||||
- [[C.]] A bypass capacitor in series with the motor’s field winding
|
||||
- [[D.]] A bypass choke in parallel with the motor’s field winding
|
||||
--
|
||||
- [[E4E06]] (C)
|
||||
What type of electrical interference can be caused by computer network equipment? #card
|
||||
- [[A.]] A loud AC hum in the audio output of your station’s receiver
|
||||
- [[B.]] A clicking noise at intervals of a few seconds
|
||||
- [[C.]] The appearance of unstable modulated or unmodulated signals at specific frequencies
|
||||
- [[D.]] A whining-type noise that continually pulses off and on
|
||||
--
|
||||
- [[E4E07]] (B)
|
||||
Which of the following can cause shielded cables to radiate or receive interference? #card
|
||||
- [[A.]] Low inductance ground connections at both ends of the shield
|
||||
- [[B.]] Common-mode currents on the shield and conductors
|
||||
- [[C.]] Use of braided shielding material
|
||||
- [[D.]] Tying all ground connections to a common point resulting in differential-mode currents in the shield
|
||||
--
|
||||
- [[E4E08]] (B)
|
||||
What current flows equally on all conductors of an unshielded multiconductor cable? #card
|
||||
- [[A.]] Differential-mode current
|
||||
- [[B.]] Common-mode current
|
||||
- [[C.]] Reactive current only
|
||||
- [[D.]] Magnetically-coupled current only
|
||||
--
|
||||
- [[E4E09]] (C)
|
||||
What undesirable effect can occur when using a noise blanker? #card
|
||||
- [[A.]] Received audio in the speech range might have an echo effect
|
||||
- [[B.]] The audio frequency bandwidth of the received signal might be compressed
|
||||
- [[C.]] Strong signals may be distorted and appear to cause spurious emissions
|
||||
- [[D.]] FM signals can no longer be demodulated
|
||||
--
|
||||
- [[E4E10]] (D)
|
||||
Which of the following can create intermittent loud roaring or buzzing AC line interference? #card
|
||||
- [[A.]] Arcing contacts in a thermostatically controlled device
|
||||
- [[B.]] A defective doorbell or doorbell transformer inside a nearby residence
|
||||
- [[C.]] A malfunctioning illuminated advertising display
|
||||
- [[D.]] All these choices are correct
|
||||
--
|
||||
- [[E4E11]] (B)
|
||||
What could be the cause of local AM broadcast band signals combining to generate spurious signals on the MF or HF bands? #card
|
||||
- [[A.]] One or more of the broadcast stations is transmitting an over-modulated signal
|
||||
- [[B.]] Nearby corroded metal connections are mixing and reradiating the broadcast signals
|
||||
- [[C.]] You are receiving skywave signals from a distant station
|
||||
- [[D.]] Your station receiver IF amplifier stage is overloaded
|
||||
--
|
||||
- [[E4E12]] (A)
|
||||
What causes interference received as a series of carriers at regular intervals across a wide frequency range? #card
|
||||
- [[A.]] Switch-mode power supplies
|
||||
- [[B.]] Radar transmitters
|
||||
- [[C.]] Wireless security camera transmitters
|
||||
- [[D.]] Electric fences
|
||||
--
|
||||
- [[E4E13]] (C)
|
||||
Where should a station AC surge protector be installed? #card
|
||||
- [[A.]] At the AC service panel
|
||||
- [[B.]] At an AC outlet
|
||||
- [[C.]] On the single point ground panel
|
||||
- [[D.]] On a ground rod outside the station
|
||||
--
|
||||
- [[E4E14]] (D)
|
||||
What is the purpose of a single point ground panel? #card
|
||||
- [[A.]] Remove AC power in case of a short-circuit
|
||||
- [[B.]] Prevent common-mode transients in multi-wire systems
|
||||
- [[C.]] Eliminate air gaps between protected and non-protected circuits
|
||||
- [[D.]] Ensure all lightning protectors activate at the same time
|
||||
Reference in New Issue
Block a user