Vocabulary Flashcards
Abbreviation for Voltage
E
Voltage is measured in __________
volts
Abbreviate for current
I
Current is measured in _________
amperes
Abbreviation for resistance
R
Resistance is measured in
Ohms
V (E) = ? times ?
V (E) = current (I) x resistance (R)
Power (P) = ? times ?
Power (P) = voltage (E) x current (I)
Abbreviation for power
P
Power is measured in______
watts
? ? ? base unit ( e.g. MHz) ? ? ? ?
giga mega kilo (base unit) milli micro nano pico
If you had an increase of 3dB = x ?
x 2
If you had an increase of 6db = x ?
x 4
If you had an increase of 10 db = x ?
x 10
Label for inductors
Henry
FET
Field Effect Transistor
What controls current flow?
transistors
What changes from AC to DC?
rectifier
What changes voltage?
transformer
What changes RF to a different band?
transverter
SSB/CW-FM switch does what?
sets amplifier for proper operation in selected mode.
What does a mixer do?
converts radio signal from one frequency to another
What does an ohm measure?
resistance
What frequencies are in the HF band?
3-30MHz
What wavelengths are in the HF band?
100m - 10m
What frequencies are in the VHF band?
30-300MHz
What wavelengths are in the VHF band?
10m - 1m
What frequencies are in the UHF band?
300-3000 MHz
What wavelengths are in the UHF band?
1m - 0.1m
What does a multimeter measure?
voltage and resistance
What does FM stand for?
frequency modulation
What is SSB?
Single side band - a type of amplitude modulation
Transmitters reduce output power to protect?
output amplifier resistors
FT8 digital mode
low signal to noise ratio - less interference
NTSC is?
analog fast color scan TV
PSK
phase shift keying - communicate via keyboard
DMR = ?
digital mobile ratio - multiplexing tech doubles capacity
Satellite operating mode:
U/V uplink 70cm downlink 2M
Doppler shift causes
change in frequency
QRM refers to?
man-made interference
QRN refers to ?
interference due to static
RACES
emergency help for government / FCC
ARES
emergency for private companies
Simplex
transmitting and receiving on the same frequency
Capacitors are measured in ____________
farads
What do capacitors do?
store electric energy
What do inductors do?
store magnetic energy
What is the purpose of nets?
To allow a number of amateurs to use a single frequency.
PL (private line) tones and codes use ______
CTCSS (continuous tone-coded squelch system)
IRLP (Internet Relay Linking Project) uses _____________
DTMF tones
What is a check?
number of words or word equivalents in the text portion of the message.
DMR talk groups allow you to _________
share a single DMR channel at different times without being heard by the other users and groups on the channel.
What kind of polarization is associated with the term “skip”?
vertical and horizontal polarization.
How fast to radio waves travel in meters? in km?
300,000,000 meters per second
300,000 km per second
What wavelengths are not affected by fog?
10m and 6m wavelengths
When is knife-edge diffraction used?
to accomplish reliable two-way communications despite obstructions
The ionosphere has little or no effect on what type of radio waves?
UHF
If you can see the other amateur station, why can probably communicate to them via VHF or UHF frequencies?
The Earth seems less curved to radio waves than to light waves.
What causes irregular fading of a RF signal?
random combining of radio waves arriving via different paths.
Propagation type sporadic E is when you hear amateur stations________
located past the horizon on 10m, 6m and 2meters.
If you hear stations on VHF that are much farther away than your repeater or line of site, it is caused by _____
auroral reflection
What property is used to describe polarization?
electric field
What type of wire should you use to handle most modern HF transceivers?
heavy-gauge wire with connections as short as possible. When voltage falls below a certain value, the radio will not operate correctly.
What digital mode pack as many different signals as possible into a 3kHz bandwidth?
FT8
Impedance is measured in _________
ohms
Nearly all mobile transceivers are designed to work with what type of electrical system?
12volts
The current flowing through each component in
parallel depends on_______________
the component’s type and value.
What happens to the current at the junction of two components in a series?
It is unchanged.
In a parallel circuit, the circuit flow for each individual component added together equals____________
total current flow for the whole parallel circuit.
Voltage across two components in parallel is ____________________
the same voltage as the source
When components are connected in series, the same current flows through all the components but _____________
the voltage drops across each component depending on the type and value of the component.
Electric current is measured in _________
amperes
What is the definition of current?
The flow of electrons in an electrical circuit.
What controls the amount of voltage from a power supply?
Regulator
What types of batteries are not rechargeable?
carbon-zinc
What can reduce overload to a VHF transceiver from a nearby FM broadcast station?
band reject filter
What is SWR (standing wave ratio)
measure of how well a load is matched to a transmission line.
Why is output power is reduced as SWR increases?
to protect the outpout amplifier transistors.
If you are told you are overdeviating what should you do?
Talk farther away from the microphone.
Power lost in a feed line is dissipated as_______
heat
What type of line has the lowest loss at VHF and UHF frequencies?
air-insulated
Which antenna is better 5/8 wavelength or quarter wavelength?
5/8
Which coaxial cable has the least amount of loss at a given frequency?
RG-8
What makes antennas to appear electrically longer?
inductors inserted in series with the radiating portion of the antenna.
If the average time for RF exposure is 6 minutes and the signal is present for 3 minutes and absent for 3 minutes then the power density permitted is_____
two times as much
FCC bulletin, computer modeling and measurement of field strength are all acceptable methods to determine_________
if your station meets FCC exposure regulation requirements.
IRLP uses what types of tones?
DTMF (dual tone multi frequency)
What is a form of amplitude modulation?
single sideband
What reduces ignition interference to a receiver?
noise blanker
Which Q signal indicates that you are changing frequency?
QSY
What antenna polarization is normally used for long-distance weak-signal CW and SSB contacts using the VHF and UHF bands?
Horizontal
What is meant by the statement that a satellite is operating in mode U/V?
The satellite frequencies are usually variable
What describes the number of times per second that al alternating current makes a complete cycle?
frequency
What is FT8
Digital mode capable of operating in low signal-to-noise conditions that transmits on 15 second intervals.
What is an ARQ transmission system?
A digital scheme whereby the receiving station detects errors and sends a request to the sending station to retransmit the information.
What component can consist of three layers of semiconductor material?
Transistor
What is the electrical difference between RG-58 and RG-8 coaxial cable?
RG-8 cable has less loss at a given frequency.
What are inputs to a satellite tracking program?
Keplerian elements
What is good practice when installing ground wires on a tower for lightning protection?
Ensure that connections are short and direct
How many volts are equal to one microvolt?
one one-millionth of a volt
What type of modulation is most commonly used for VHF packet radio transmissions?
FM
What type of connector is most suitable for frequencies above 400 MHz?
Type N connector
Electrical current is measured in what unit?
amperes = measure electrical current
volts = measures electric potential, aka electromotive force, analogous to water pressure
ohms = measures resistance
watts = measures power - the rate at which work is done
What is an advantage of SSB over FM for voice transmissions?
SSB signals have a narrower bandwidth
What factors affect RF exposure of people near an amateur station antenna?
All of these choices are correct.
Frequency, power, distance and radiation
When may an amateur station transmit without on-the-air identification?
when transmitting signals to control model craft
What class of electronic components uses a voltage or current signal to control current flow?
transistors
Which of the following best describes Broadband-Hamnet, also referred to as a high-speed multi-media network?
An amateur-radio-based data network using commercial Wi-Fi gear with modified firmware
What is a safety hazard of a 12 volt storage battery?
shorting the terminals can cause burns, fire, or an explosion.
What is the proper location for an external SWR meter?
In series with the feed line, between the transmitter and antenna.
What is a common reason to use shielded wire?
To prevent coupling of unwanted signals to or from the wire
What is combined with an inductor to make a tuned circuit?
Resistor
What property of a radio wave is used to describe its polarization?
orientation of the electric field
What is the FCC Part 97 definition of a beacon?
An amateur station transmitting communications for the purposes of observing propagation or related experimental activities.
What measurement is commonly made using a multimeter?
voltage and resistance
What is a good way to judge whether your uplink power is neither too low nor too high?
Your signal strength on the downlink should be about the same as the beacon.
What method of call sign identification is required for a station transmitting phone signals?
send the call sign using a CW or phone emission
In the US, what is connect to the green wire in a three-wire electrical AC plug?
Equipment ground
What best describes DMR (Digital Mobile Radio)?
A technique for time-multiplexing two digital voice signals on a single 12.5 kHz repeater channel
What method is used to locate sources of noise interference or jamming?
radio direction finding
What component can be used as an electronic switch or amplifier?
Transistor
What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz?
19 inches
SSB uses what KHz?
3 KHz
What is the impedance of most coaxial cables used in amateur radio installations?
50 ohms
What is the most common offset in the 2 meter band?
-600 or +600 KHz
What is a common repeater offset for the 70cm band?
-5 or +5 MHz
The approximate length, in inches of a quarter-wavelength vertical antenna for 146MHz is________
19 inches
The approximate length, in inches, of a half-wavelength 6 meter dipole antenna is?
112 inches
What is the maximum power level that an amateur station may use at VHF frequencies before an RF exposure evaluation is required?
50 watts PEP at the attena
What is the maximum peak envelope power output for Technician class operators using their assigned portions of the HF bands?
200 watts
Except for some specific restrictions, what is the maximum peak envelope power output for Technician class operators using frequencies above 30 MHz
1500 watts
What band is best suited for communicating via meteor scatter?
6 meter band
Technician class licensee may operate on frequencies above 30 MHz using the full power authorized for amateur transmissions which is ____?
1500 watts
What is the lowest value for maximum permissible exposure limit?
50 MHz
What are the frequency limits of the UHF spectrum?
300-3000 MHz
Which frequency is within the 6 meter amateur band?
52.525 MHz
What is the approximate bandwidth of a SSB voice signal?
3 kHz
What is the approximate maximum bandwidth required to transmit a CW signal?
150 Hz
Which band follows the sun and is good during daylight hours?
10m band
What band is often referred to as the “magic band”?
6m
What is the approximate bandwidth of a VHF repeater FM phone signal?
Between 10 and 15 KHz
219 - 220 MHz is what band?
1.25 meter band
Only the 1.25 meter band amateurs can only use it for?
fixed digital message forwarding
The 2 meter band has a frequency of what?
144 MHz
What HF band has frequencies available to the Technician class operator for RTTY and data transmissions?
10 meter band only
Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for CW reception?
500 Hz
What is the typical bandwidth of analog fast-scan TV transmissions on the 70 centimeter band?
About 6 MHz
Upper side band SSB is used for what?
10m, HF, VHF, UHF
What type of circuit controls the amount of voltage from a power supply?
regulator
Which of the following is true of PL-259 type coax connectors?
They are commonly used at HF frequencies.
Why is coaxial cable the most common feed line selected for amateur radio antenna systems?
It is easy to use and requires few special installation considerations
What is the function of the SSB/CW-FM switch on a VHF power amplifier?
Set the amplifier for proper operation in the selected mode.
What electrical component can amplify signals?
Transistors
What is the name of a circuit the generates a signal at a specific frequency?
Oscillator
Which of the following is true when installing grounding conductors used for lightning protection?
sharp bends must be avoided
What class of electronic components uses a voltage or current signal to control current flow?
Transistors
What electrical parameter is controlled by a potentiometer?
Resistance
What brief statement indicates that you are listening on a repeater and looking for a contact?
Your call sign.
What is an example of automatic control?
repeater operation
Which of the following is combined with an inductor to make a tuned circuit?
capacitor
What is remote control as defined in Part 97?
Operating the station over the internet.
Which of the following types of emission has the narrowest bandwidth?
CW
What type of electrical component consists of two or emore conductive surfaces separated by an insulator?
Capacitor
Which of the following devices or circuits changes an alternating current into a varying direct current signal?
rectifier
10.) Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for SSB reception?
500 Hz
1000 Hz
2400 Hz
5000 Hz
2400 Hz
9) Which of the following is a common repeater frequency offset in the 2-meter band?
Plus or minus 600 kHz
8) What property of a radio wave is used to describe its polarization?
The orientation of the electric field
7) What is the advantage of having multiple receive bandwidth choices on a multimode transceiver?
Permits noise or interference reduction by selecting a bandwidth matching the mode.
What is another way to specify a radio signal frequency of 1,500,000 hertz?
1500 kHz
1500 MHz
15 GHz
150 kHz
1500 kHz
5) What is the approximate bandwidth of a SSB voice signal?
3 kHz
4) What is the function of the SSB/CW-FM switch on a VHF power amplifier?
Set the amplifier for proper operation in the selected mode.
3) What is the approximate bandwidth of a VHF repeater FM phone signal?
Between 10 and 15 kHz
2) What happens to current at the junction of two components in series?
It is unchanged.
1) Which of the following is an example of remote control as defined in Part 97?
Operating the station over the internet.
