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Transcript
Technician Licensing Class
T 4 A - T4B
Valid July 1, 2014
Through
June 30, 2018
1
T4A
• Some microphone connectors on amateur transceivers
include push-to-talk and voltages for powering the
microphone.
T4A01
2
T4A
• Computers might be used as part of an amateur radio
station:
 For logging contacts and contact information
 For sending and/or receiving CW
 For generating and decoding digital signals
All of these choices are correct
T4A02
3
T4A
• A good reason to use a regulated power supply for
communications equipment is that it prevents voltage
fluctuations from reaching sensitive circuits.
T4A03
• To reduce harmonic emissions
from your station install a filter
between the transmitter and
the antenna.
T4A04
4
T4A
• An in-line SWR meter should be connected to monitor
the standing wave ratio of the station antenna system in
series with the feed line, between the transmitter and
antenna.
T4A05
5
T4A
• A terminal node controller
would be connected between
a transceiver and computer
in a packet radio station.
T4A06
• When conducting digital communications using a
computer the sound card provides audio to the
microphone input and converts received audio to digital
form.
6
T4A07
T4A
• The flat strap type of conductor is the best to use for RF
grounding.
T4A08
• Use a ferrite choke to
cure distorted audio
caused by RF current
flowing on the shield
of a microphone cable.
T4A09
7
T4A
• A source of a high-pitched
whine that varies with
engine speed in a mobile
transceiver’s receive audio
is the alternator.
T4A10
• The negative return connection of a mobile transceiver
power cable should be connected at the battery or engine
block ground strap.
T4A11
• If another operator reports a variable high-pitched whine
on the audio from your mobile transmitter there is noise
on the vehicle’s electrical system being transmitted along
with your speech audio.
8
T4A12
T4B
• If a transmitter is operated with the microphone gain set
too high the output signal might become distorted
• A keypad or VFO knob can be used to enter the
operating frequency on a modern transceiver.
T4B01
T4B02
KeyPad
VFO
• The squelch control on a transceiver will mute the
receiver output noise when no signal is being received.9
T4B03
Run Some Interference Protection
• Storing popular frequencies in a memory channel is a
way to enable quick access to favorite frequencies on
your transceiver.
T4B04
• To reduce ignition interference to a receiver turn on the
noise blanker.
T4B05
Not on common
FM handheld or
mobile FM
radios.
On bigger highfrequency, multimode
transceiver.
PreAmp built in
NB – Noise Blanker
10
T4B
• The receiver RIT or clarifier controls could be used if the
voice pitch of a single-sideband signal seems too high or
low.
T4B06
• “RIT” means Receiver Incremental Tuning.
T4B07
11
T4B
• The advantage of having multiple receive bandwidth
choices on a multimode transceiver is that it permits
noise or interference reduction by selecting a bandwidth
matching the mode.
T4B08
12
T4B
• 2400 Hz is an appropriate receive filter bandwidth to
select in order to minimize noise and interference for
SSB reception. T4B09
13
T4B
• 500 Hz is an appropriate receive filter bandwidth to
select in order to minimize noise and interference for
CW reception.
T4B10
14
T4B
• The difference between the repeater’s transmit and
receive frequencies is called “repeater offset”.
T4B11
Frequency Range
145.200-145.495 MHz
146.610-146.995 MHz
147.000-147.395
Mhz
442.000-444.995 Mhz
447.000-449.995
Mhz
Shift Direction
Negative
Positive
Positive
Positive
Negative
• The function of automatic gain control or AGC is to keep
received audio relatively constant.
T4B12
15
Element 2 Technician Class
Question Pool
T 4 A –T 4 B
Valid July 1, 2014
Through
June 30, 2018
16
T4A01
Which of the following is true concerning the
microphone connectors on amateur transceivers?
A. All transceivers use the same microphone
connector type
B. Some connectors include push-to-talk and
voltages for powering the microphone
C. All transceivers using the same connector
type are wired identically
D. Un-keyed connectors allow any microphone
to be connected
17
T4A02
How might a computer be used as part of an
amateur radio station?
A. For logging contacts and contact
information
B. For sending and/or receiving CW
C. For generating and decoding digital signals
D. All of these choices are correct
18
T4A03
Which is a good reason to use a regulated power
supply for communications equipment?
A. It prevents voltage fluctuations from reaching
sensitive circuits
B. A regulated power supply has FCC approval
C. A fuse or circuit breaker regulates the power
D. Power consumption is independent of load
19
T4A04
Where must a filter be installed to reduce
harmonic emissions from your station?
A.
B.
C.
D.
Between the transmitter and the antenna
Between the receiver and the transmitter
At the station power supply
At the microphone
20
T4A05
Where should an in-line SWR meter be connected
to monitor the standing wave ratio of the station
antenna system?
A. In series with the feed line, between the
transmitter and antenna
B. In series with the station’s ground
C. In parallel with the push-to-talk line and the
antenna
D. In series with the power supply cable, as
close as possible to the radio
21
T4A06
Which of the following would be connected
between a transceiver and computer in a packet
radio station?
A.
B.
C.
D.
Transmatch
Mixer
Terminal node controller
Antenna
22
T4A07
How is the computer’s sound card used when
conducting digital communications using a
computer?
A. The sound card communicates between the
computer CPU and the video display
B. The sound card records the audio frequency
for video display
C. The sound card provides audio to the
microphone input and converts received audio
to digital form
D. All of these choices are correct
23
T4A08
Which type of conductor is best to use for RF
grounding?
A.
B.
C.
D.
Round stranded wire
Round copper-clad steel wire
Twisted-pair cable
Flat strap
24
T4A09
Which of the following could you use to cure
distorted audio caused by RF current flowing on
the shield of a microphone cable?
A.
B.
C.
D.
Band-pass filter
Low-pass filter
Preamplifier
Ferrite choke
25
T4A10
What is the source of a high-pitched whine that
varies with engine speed in a mobile transceiver’s
receive audio?
A.
B.
C.
D.
The ignition system
The alternator
The electric fuel pump
Anti-lock braking system controllers
26
T4A11
Where should the negative return
connection of a mobile transceiver’s
power cable be connected?
A.
B.
C.
D.
At the battery or engine block ground strap
At the antenna mount
To any metal part of the vehicle
Through the transceiver’s mounting bracket
27
T4A12
What could be happening if another operator
reports a variable high-pitched whine on the
audio from your mobile transmitter?
A. Your microphone is picking up noise from an
open window
B. You have the volume on your receiver set too
high
C. You need to adjust your squelch control
D. Noise on the vehicle’s electrical system is
being transmitted along with your speech
audio
28
T4B01
What may happen if a transmitter is operated with
the microphone gain set too high?
A.
B.
C.
D.
The output power might be too high
The output signal might become distorted
The frequency might vary
The SWR might increase
29
T4B02
Which of the following can be used to enter the
operating frequency on a modern transceiver?
A.
B.
C.
D.
The keypad or VFO knob
The CTCSS or DTMF encoder
The Automatic Frequency Control
All of these choices are correct
30
T4B03
What is the purpose of the squelch control on a
transceiver?
A.
B.
C.
D.
To set the highest level of volume desired
To set the transmitter power level
To adjust the automatic gain control
To mute receiver output noise when no
signal is being received
31
T4B04
What is a way to enable quick access to a favorite
frequency on your transceiver?
A. Enable the CTCSS tones
B. Store the frequency in a memory
channel
C. Disable the CTCSS tones
D. Use the scan mode to select the desired
frequency
32
T4B05
Which of the following would reduce
ignition interference to a receiver?
A.
B.
C.
D.
Change frequency slightly
Decrease the squelch setting
Turn on the noise blanker
Use the RIT control
33
T4B06
Which of the following controls could be used if the
voice pitch of a single-sideband signal seems too
high or low?
A.
B.
C.
D.
The AGC or limiter
The bandwidth selection
The tone squelch
The receiver RIT or clarifier
34
T4B07
What does the term "RIT" mean?
A.
B.
C.
D.
Receiver Input Tone
Receiver Incremental Tuning
Rectifier Inverter Test
Remote Input Transmitter
35
T4B08
What is the advantage of having multiple
receive bandwidth choices on a multimode
transceiver?
A. Permits monitoring several modes at once
B. Permits noise or interference reduction by
selecting a bandwidth matching the mode
C. Increases the number of frequencies that can
be stored in memory
D. Increases the amount of offset between
receive and transmit frequencies
36
T4B09
Which of the following is an appropriate receive
filter bandwidth to select in order to minimize noise
and interference for SSB reception?
A.
B.
C.
D.
500 Hz
1000 Hz
2400 Hz
5000 Hz
37
T4B10
Which of the following is an appropriate receive filter
bandwidth to select in order to minimize noise and
interference for CW reception?
A.
B.
C.
D.
500 Hz
1000 Hz
2400 Hz
5000 Hz
38
Which of the following describes the
common meaning of the term
“repeater
offset”?
T4B11
A. The distance between the repeater’s
transmit and receive antennas
B. The time delay before the repeater timer
resets
C. The difference between the repeater’s
transmit and receive frequencies
D. To match the antenna impedance to the
feed line impedance
39
T4B12
What is the function of automatic gain control or
AGC?
A.
B.
C.
D.
To keep received audio relatively constant
To protect an antenna from lightning
To eliminate RF on the station cabling
asymmetric goniometer control used for
antenna matching
40