Amateur Extra Class Practice Test

Select the most correct answer for each question, then submit your practice test to check your score. This practice test randomly pulls one question from each topic in the Amateur Extra pool.

Good Luck!


What is the gain-bandwidth of an operational amplifier?

The maximum frequency for a filter circuit using that type of amplifier
The frequency at which the open-loop gain of the amplifier equals one
The gain of the amplifier at a filter's cutoff frequency
The frequency at which the amplifier's offset voltage is zero


Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

Point 1
Point 3
Point 7
Point 8
Circuit Diagram


Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Mountain ranges
Bodies of water
Urban areas


What does the 304A solar parameter measure?

The ratio of x-ray flux to radio flux, correlated to sunspot number
UV emissions at 304 angstroms, correlated to the solar flux index
The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
The solar emission at 304 GHz, correlated to x-ray flare levels


Why is de-emphasis commonly used in FM communications receivers?

For compatibility with transmitters using phase modulation
To reduce impulse noise reception
For higher efficiency
To remove third-order distortion products


What is one advantage of the JT65 mode?

Uses only a 65 Hz bandwidth
The ability to decode signals which have a very low signal-to-noise ratio
Easily copied by ear if necessary
Permits fast-scan TV transmissions over narrow bandwidth


What special operating frequency restrictions are imposed on slow scan TV transmissions?

None; they are allowed on all amateur frequencies
They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
They are restricted to phone band segments
They are not permitted above 54 MHz


What is susceptance?

The magnetic impedance of a circuit
The ratio of magnetic field to electric field
The imaginary part of admittance
A measure of the efficiency of a transformer


Why are switching amplifiers more efficient than linear amplifiers?

Switching amplifiers operate at higher voltages
The power transistor is at saturation or cutoff most of the time
Linear amplifiers have high gain resulting in higher harmonic content
Switching amplifiers use push-pull circuits


Which of the following best describes the Volunteer Examiner accreditation process?

Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
The prospective VE obtains accreditation from the FCC
The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner


What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

The front-to-back ratio increases
The front-to-back ratio decreases
The frequency response is widened over the whole frequency band
The SWR is reduced


Which of the following is a common use of a Schottky diode?

As a rectifier in high current power supplies
As a variable capacitance in an automatic frequency control circuit
As a constant voltage reference in a power supply
As a VHF/UHF mixer or detector


What type of circuit is shown in Figure E7-2?

Switching voltage regulator
Grounded emitter amplifier
Linear voltage regulator
Monostable multivibrator
Circuit Diagram


What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Powdered-iron cores generally have greater initial permeability
Powdered-iron cores generally maintain their characteristics at higher currents
Powdered-iron cores generally require fewer turns to produce a given inductance
Powdered-iron cores use smaller diameter wire for the same inductance


What is digital time division multiplexing?

Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
Two or more signals are arranged to share discrete time slots of a data transmission
Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
Two or more signals are quadrature modulated to increase bandwidth efficiency


How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

The low-angle radiation decreases
Additional higher vertical angle lobes will appear
Fewer vertical angle lobes will be present
The low-angle radiation increases


What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

2.5 to 1
25 to 1
1 to 1
100 to 1


Which of these digital modes has the fastest data throughput under clear communication conditions?

170 Hz shift, 45 baud RTTY
300 baud packet


How is the Q of an RLC parallel resonant circuit calculated?

Reactance of either the inductance or capacitance divided by the resistance
Reactance of either the inductance or capacitance multiplied by the resistance
Resistance divided by the reactance of either the inductance or capacitance
Reactance of the inductance multiplied by the reactance of the capacitance


Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

CEPT agreement
IARP agreement
ITU reciprocal license
All these choices are correct


Which of the following is a common use for a Smith chart?

Determine the length and position of an impedance matching stub
Determine the impedance of a transmission line, given the physical dimensions
Determine the gain of an antenna given the physical and electrical parameters
Determine the loss/100 feet of a transmission line, given the velocity factor and conductor materials


What type of transmission line is used for connections to MMICs?

Miniature coax
Circular waveguide
Parallel wire


What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and that uses a 455 kHz IF frequency?

13.845 MHz
14.755 MHz
14.445 MHz
15.210 MHz


What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

Amplifier desensitization
Adjacent channel interference


What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historic Places?

A proposal must be submitted to the National Park Service
A letter of intent must be filed with the Environmental Protection Agency
An Environmental Assessment must be submitted to the FCC
A form FSD-15 must be submitted to the Department of the Interior


What are Keplerian elements?

Parameters that define the orbit of a satellite
Phase reversing elements in a Yagi antenna
High-emission heater filaments used in magnetron tubes
Encrypting codes used for spread spectrum modulation


What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

0.1 Hz
0.3 kHz
0.5 kHz
1.0 kHz


What is the term for the long path opening that exists between two points on the Earth which are simultaneously near sunrise and sunset?

Sporadic E


What are three oscillator circuits used in amateur radio equipment?

Taft, Pierce and negative feedback
Pierce, Fenner and Beane
Taft, Hartley and Pierce
Colpitts, Hartley and Pierce


Which of the following best describes the term self-spotting? in connection with HF contest operating?

The often-prohibited practice of posting one's own call sign and frequency on a spotting network
The acceptable practice of manually posting the call signs of stations on a spotting network
A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station


Which of the following amateur stations may transmit one-way communications?

A space station, beacon station, or telecommand station
A local repeater or linked repeater station
A message forwarding station or automatically controlled digital station
All these choices are correct


In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

75 degrees
50 degrees
25 degrees
30 degrees
Circuit Diagram


What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

4 bits
6 bits
8 bits
10 bits


What is the main drawback of a small wire-loop antenna for direction finding?

It has a bidirectional pattern
It has no clearly defined null
It is practical for use only on VHF and higher bands
All these choices are correct


What is one type of electrical interference that might be caused by a nearby personal computer?

A loud AC hum in the audio output of your station receiver
A clicking noise at intervals of a few seconds
The appearance of unstable modulated or unmodulated signals at specific frequencies
A whining type noise that continually pulses off and on


Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

Connect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
Insert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
Insert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable
Connect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna


Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

A Phase Inverter Load network
A Pi-network with an additional series inductor on the output
A network with only three discrete parts
A matching network in which all components are isolated from ground


What is the power factor of an RL circuit having a 30-degree phase angle between the voltage and the current?



Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
The equipment dealer assembled it from a kit
It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
It was imported from a manufacturer in another country and was certificated by that country's government


What impedance does a 1/2-wavelength transmission line present to a generator when the line is shorted at the far end?

Very high impedance
Very low impedance
The same as the characteristic impedance of the line
The same as the output impedance of the generator


How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?



Which of these materials is most commonly used to create photoconductive devices?

A crystalline semiconductor
An ordinary metal
A heavy metal
A liquid semiconductor


How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

100 watts
125 watts
25 watts
75 watts


Why are received spread spectrum signals resistant to interference?

Signals not using the spread spectrum algorithm are suppressed in the receiver
The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
The receiver is always equipped with a digital blanker
If interference is detected by the receiver it will signal the transmitter to change frequencies


What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Polychlorinated biphenyls
Polymorphic silicon


In Figure E6-3, what is the schematic symbol for a NOR gate?

Circuit Diagram


Which of the following can divide the frequency of a pulse train by 2?

An XOR gate
A flip-flop
An OR gate
A multiplexer


In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

Circuit Diagram


Which of the following limits the highest frequency signal that can be accurately displayed on a digital oscilloscope?

Sampling rate of the analog-to-digital converter
Amount of memory
Q of the circuit
All these choices are correct


What is an isotropic antenna?

A grounded antenna used to measure Earth conductivity
A horizontally polarized antenna used to compare Yagi antennas
A theoretical, omnidirectional antenna used as a reference for antenna gain
A spacecraft antenna used to direct signals toward Earth