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!


Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

Higher noise figures
Higher electron mobility
Lower junction voltage drop
Lower transconductance


What may be the penalty for a VE who fraudulently administers or certifies an examination?

Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
A fine of up to $1000 per occurrence
A sentence of up to one year in prison
All these choices are correct


What is current in the primary winding of a transformer called if no load is attached to the secondary?

Magnetizing current
Direct current
Excitation current
Stabilizing current


Which of the following types of noise can often be reduced with a digital signal processing noise filter?

Broadband white noise
Ignition noise
Power line noise
All these choices are correct


What type of computer program technique is commonly used for modeling antennas?

Graphical analysis
Method of Moments
Mutual impedance analysis
Calculus differentiation with respect to physical properties


Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?



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


Which of the following components can be used to reduce thermal drift in crystal oscillators?

NP0 capacitors
Toroidal inductors
Wirewound resistors
Non-inductive resistors


What is a common use for point-contact diodes?

As a constant current source
As a constant voltage source
As an RF detector
As a high-voltage rectifier


Where is the impedance of a pure resistance plotted on rectangular coordinates?

On the vertical axis
On a line through the origin, slanted at 45 degrees
On a horizontal line, offset vertically above the horizontal axis
On the horizontal axis


What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

0.23 volts
2.3 volts
-0.23 volts
-2.3 volts
Circuit Diagram


What are the two families of circles and arcs that make up a Smith chart?

Resistance and voltage
Reactance and voltage
Resistance and reactance
Voltage and impedance


What is the function of a sense antenna?

It modifies the pattern of a DF antenna array to provide a null in one direction
It increases the sensitivity of a DF antenna array
It allows DF antennas to receive signals at different vertical angles
It provides diversity reception that cancels multipath signals


What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2 wavelength apart and fed in phase?

A Figure-8 broadside to the axis of the array
A Figure-8 end-fire along the axis of the array


What logical operation is performed by an exclusive NOR gate?

It produces logic 0 at its output only if all inputs are logic 0
It produces logic 1 at its output only if all inputs are logic 1
It produces logic 0 at its output if only one input is logic 1
It produces logic 1 at its output if only one input is logic 1


What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

7.0 meters
8.5 meters
10.6 meters
13.3 meters


What does a receiver noise floor of -174 dBm represent?

The minimum detectable signal as a function of receive frequency
The theoretical noise in a 1 Hz bandwidth at the input of a perfect receiver at room temperature
The noise figure of a 1 Hz bandwidth receiver
The galactic noise contribution to minimum detectable signal


How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

8 multiplied by the gain of the input amplifier
256 divided by the gain of the input amplifier


In Figure E6-3, what is the schematic symbol for a NAND gate?

Circuit Diagram


What type of satellite appears to stay in one position in the sky?



Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

A series current source
A series regulator
A shunt regulator
A shunt current source


Why are there separate electric (E) and magnetic (H) field MPE limits?

The body reacts to electromagnetic radiation from both the E and H fields
Ground reflections and scattering make the field strength vary with location
E field and H field radiation intensity peaks can occur at different locations
All these choices are correct


What term describes station output, taking into account all gains and losses?

Power factor
Half-power bandwidth
Effective radiated power
Apparent power


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 is the maximum permitted transmitter output power when operating a model craft by telecommand?

1 watt
2 watts
5 watts
100 watts


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 technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

Transmitting on channels shared with cable TV
Using converted satellite TV dishes
Transmitting on the abandoned TV channel 2
Using USB and demodulating the signal with a computer sound card


What technique minimizes the bandwidth of a PSK31 signal?

Zero-sum character encoding
Reed-Solomon character encoding
Use of sinusoidal data pulses
Use of trapezoidal data pulses


What happens as the Q of an antenna increases?

SWR bandwidth increases
SWR bandwidth decreases
Gain is reduced
More common-mode current is present on the feed line


Which of the following reduces the likelihood of receiver desensitization?

Decrease the RF bandwidth of the receiver
Raise the receiver IF frequency
Increase the receiver front end gain
Switch from fast AGC to slow AGC


How many watts are consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere?

70.7 watts
100 watts
141.4 watts
200 watts


What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

It is at a minimum
It is at a maximum
It equals 1 divided by the quantity 2 times pi, multiplied by the square root of inductance L multiplied by capacitance C
It equals 2 multiplied by pi, multiplied by frequency, multiplied by inductance


Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

At the lowest frequency of the channel
At the center frequency of the channel
At the highest frequency of the channel
On any frequency where the signal's sidebands are within the channel


How is the timing of FT4 contacts organized?

By exchanging ACK/NAK packets
Stations take turns on alternate days
Alternating transmissions at 7.5 second intervals
It depends on the lunar phase


What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Switch to a higher frequency HF band
Switch to a lower frequency HF band
Wait 90 minutes or so for the signal degradation to pass
Wait 24 hours before attempting another communication on the band


What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

14 degrees with the voltage lagging the current
14 degrees with the voltage leading the current
76 degrees with the voltage lagging the current
76 degrees with the voltage leading the current


What is the beta of a bipolar junction transistor?

The frequency at which the current gain is reduced to 0.707
The change in collector current with respect to base current
The breakdown voltage of the base to collector junction
The switching speed


Which of the following describes a method of establishing EME contacts?

Time synchronous transmissions alternately from each station
Storing and forwarding digital messages
Judging optimum transmission times by monitoring beacons reflected from the moon
High-speed CW identification to avoid fading


What is the primary purpose of phasing lines when used with an antenna having multiple driven elements?

It ensures that each driven element operates in concert with the others to create the desired antenna pattern
It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
It allows single-band antennas to operate on other bands
It creates a low-angle radiation pattern


What is the advantage of including parity bits in ASCII characters?

Faster transmission rate
The signal can overpower interfering signals
Foreign language characters can be sent
Some types of errors can be detected


What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?



Which of the following types of communications may be transmitted to amateur stations in foreign countries?

Business-related messages for non-profit organizations
Messages intended for users of the maritime satellite service
Communications incidental to the purpose of the amateur service and remarks of a personal nature
All these choices are correct


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


How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Loosely couple the analyzer near the antenna base
Connect the analyzer via a high-impedance transformer to the antenna
Loosely couple the antenna and a dummy load to the analyzer
Connect the antenna feed line directly to the analyzer's connector


By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

By approximately 15 percent of the distance
By approximately twice the distance
By approximately 50 percent of the distance
By approximately four times the distance


What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

0.1 V
0.5 V
1.5 V
12 V


Where on the load line of a Class A common emitter amplifier would bias normally be set?

Approximately halfway between saturation and cutoff
Where the load line intersects the voltage axis
At a point where the bias resistor equals the load resistor
At a point where the load line intersects the zero bias current curve


Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

The relative frequencies of the individual crystals
The DC voltage applied to the quartz crystal
The gain of the RF stage preceding the filter
The amplitude of the signals passing through the filter


What is the primary characteristic of chordal hop propagation?

Propagation away from the great circle bearing between stations
Successive ionospheric refractions without an intermediate reflection from the ground
Propagation across the geomagnetic equator
Signals reflected back toward the transmitting station


Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
You must submit engineering drawings to the FAA
You must file an Environmental Impact Statement with the EPA before construction begins
You must obtain a construction permit from the airport zoning authority