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 necessary bandwidth of a 13-WPM international Morse code transmission?

Approximately 13 Hz
Approximately 26 Hz
Approximately 52 Hz
Approximately 104 Hz


What is susceptance?

The magnetic impedance of a circuit
The ratio of magnetic field to electric field
The inverse of reactance
A measure of the efficiency of a transformer


Which of the following best describes electromagnetic waves traveling in free space?

Electric and magnetic fields become aligned as they travel
The energy propagates through a medium with a high refractive index
The waves are reflected by the ionosphere and return to their source
Changing electric and magnetic fields propagate the energy


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 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


What do the terms L band and S band specify with regard to satellite communications?

The 23 centimeter and 13 centimeter bands
The 2 meter and 70 centimeter bands
FM and Digital Store-and-Forward systems
Which sideband to use


Which of the following is a common use of a hot-carrier diode?

As balanced mixers in FM generation
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


When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

Resistive component
Reactive component
The sum of the reactive and resistive components
The difference between the resistive and reactive components


What is one advantage of using JT65 coding?

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


How is positive feedback supplied in a Pierce oscillator?

Through a tapped coil
Through link coupling
Through a neutralizing capacitor
Through a quartz crystal


What do the arcs on a Smith chart represent?

Points with constant resistance
Points with constant reactance


Which of the following constitutes a spurious emission?

An amateur station transmission made at random without the proper call sign identification
A signal transmitted to prevent its detection by any station other than the intended recipient
Any transmitted signal that unintentionally interferes with another licensed radio station
An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted


What is transequatorial propagation?

Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
Propagation between any two points located on the magnetic equator
Propagation between two continents by way of ducts along the magnetic equator
Propagation between two stations at the same latitude


Which of the following can increase Q for inductors and capacitors?

Lower losses
Lower reactance
Lower self-resonant frequency
Higher self-resonant frequency


Which type of digital mode does not support keyboard-to-keyboard operation?



When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

The exact upper band edge
300 Hz below the upper band edge
1 kHz below the upper band edge
3 kHz below the upper band edge


What class of licensee is authorized to be the control operator of a space station?

All except Technician Class
Only General, Advanced or Amateur Extra Class
Any class with appropriate operator privileges
Only Amateur Extra Class


Which of these materials is affected the most by photoconductivity?

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


What is the function of a DX QSL Manager?

To allocate frequencies for DXpeditions
To handle the receiving and sending of confirmation cards for a DX station
To run a net to allow many stations to contact a rare DX station
To relay calls to and from a DX station


Why are switching amplifiers more efficient than linear amplifiers?

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


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



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 are some of the differences between the Baudot digital code and ASCII?

Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes


What is the triangulation method of direction finding?

The geometric angles of sky waves from the source are used to determine its position
A fixed receiving station plots three headings to the signal source
Antenna headings from several different receiving locations are used to locate the signal source
A fixed receiving station uses three different antennas to plot the location of the signal source


What is a truth table?

A table of logic symbols that indicate the high logic states of an op-amp
A diagram showing logic states when the digital device output is true
A list of inputs and corresponding outputs for a digital device
A table of logic symbols that indicate the logic states of an op-amp


What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Photocopy all examination documents and forward them to the FCC for processing
Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
Issue the examinee the new or upgrade license
All these choices are correct


What is one characteristic of a switching electronic voltage regulator?

The resistance of a control element is varied in direct proportion to the line voltage or load current
It is generally less efficient than a linear regulator
The controlled device's duty cycle is changed to produce a constant average output voltage
It gives a ramp voltage at its output


Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

You must identify in the official language of the country in which you are operating
The U.S. embassy must approve of your operation
You must bring a copy of FCC Public Notice DA 11-221
You must append "/CEPT" to your call sign


Which of the following types of receiver noise can often be reduced with a DSP noise filter?

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


What is a disadvantage of using a multiband trapped antenna?

It might radiate harmonics
It radiates the harmonics and fundamental equally well
It is too sharply directional at lower frequencies
It must be neutralized


What is the purpose of the series capacitor in a gamma-type antenna matching network?

To provide DC isolation between the feed line and the antenna
To cancel the inductive reactance of the matching network
To provide a rejection notch that prevents the radiation of harmonics
To transform the antenna impedance to a higher value


What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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


Which of the following is a characteristic of a good DC voltmeter?

High reluctance input
Low reluctance input
High impedance input
Low impedance input


What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?



Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

440 MHz - 450 MHz
53 MHz - 54 MHz
222 MHz - 223 MHz
420 MHz - 430 MHz


What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Detector noise
Induction motor noise
Receiver front-end noise
Atmospheric noise


How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

400 watts
80 watts
2000 watts
50 watts


Which of the following is true of a charge-coupled device (CCD)?

Its phase shift changes rapidly with frequency
It is a CMOS analog-to-digital converter
It samples an analog signal and passes it in stages from the input to the output
It is used in a battery charger circuit


How does a diode detector function?

By rectification and filtering of RF signals
By breakdown of the Zener voltage
By mixing signals with noise in the transition region of the diode
By sensing the change of reactance in the diode with respect to frequency


When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Only the most powerful transmitter
Only commercial transmitters
Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
Each transmitter operating with a duty-cycle greater than 50 percent


How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output


Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Cross-modulation of the desired signal and desensitization from strong adjacent signals
Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
Cross-modulation of the desired signal and insufficient audio power to operate the speaker
Oscillator instability and severe audio distortion of all but the strongest received signals


In Figure E6-5, what is the schematic symbol for a NOR gate?

Circuit Diagram


Why does a PN-junction diode not conduct current when reverse biased?

Only P-type semiconductor material can conduct current
Only N-type semiconductor material can conduct current
Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator


What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

10 meters
6.9 meters
24 meters
50 meters


What is meant by the term op-amp input offset voltage?

The output voltage of the op-amp minus its input voltage
The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
The differential input voltage needed to bring the open loop output voltage to zero
The potential between the amplifier input terminals of the op-amp in an open loop condition


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


How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

35 turns
13 turns
79 turns
141 turns


What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

45 degrees
75 degrees
7.5 degrees
25 degrees
Circuit Diagram


Why would one need to know the feed point impedance of an antenna?

To match impedances in order to minimize standing wave ratio on the transmission line
To measure the near-field radiation density from a transmitting antenna
To calculate the front-to-side ratio of the antenna
To calculate the front-to-back ratio of the antenna


What is the effect of aliasing in a digital or computer-based oscilloscope?

False signals are displayed
All signals will have a DC offset
Calibration of the vertical scale is no longer valid
False triggering occurs