Ham Extra License Practice Quiz
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E0A08: What does SAR measure?
Synthetic Aperture Ratio of the human body
Signal Amplification Rating
The rate at which RF energy is absorbed by the body
The rate of RF energy reflected from stationary terrain
E1A08: If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?
The control operator of the packet bulletin board station
The control operator of the originating station
The control operators of all the stations in the system
The control operators of all the stations in the system not authenticating the source from which they accept communications
E1B12: What is the highest modulation index permitted at the highest modulation frequency for angle modulation?
.5
1.0
2.0
3.0
E1C02: What is meant by automatic control of a station?
The use of devices and procedures for control so that the control operator does not have to be present at a control point
A station operating with its output power controlled automatically
Remotely controlling a station's antenna pattern through a directional control link
The use of a control link between a control point and a locally controlled station
E1D07: Which amateur service HF bands have frequencies authorized to space stations?
Only 40m, 20m, 17m, 15m, 12m and 10m
Only 40m, 20m, 17m, 15m and 10m bands
40m, 30m, 20m, 15m, 12m and 10m bands
All HF bands
E1E05: What is the minimum passing score on amateur operator license examinations?
Minimum passing score of 70%
Minimum passing score of 74%
Minimum passing score of 80%
Minimum passing score of 77%
E1F09: Which of the following conditions apply when transmitting spread spectrum emission?
A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
The transmission must not be used to obscure the meaning of any communication
All of these choices are correct
E2A03: What is the orbital period of an Earth satellite?
The point of maximum height of a satellite's orbit
The point of minimum height of a satellite's orbit
The time it takes for a satellite to complete one revolution around the Earth
The time it takes for a satellite to travel from perigee to apogee
E2B17: What is the approximate bandwidth of a slow-scan TV signal?
600 Hz
3 kHz
2 MHz
6 MHz
E2C09: How does the spread-spectrum technique of frequency hopping work?
If interference is detected by the receiver it will signal the transmitter to change frequencies
If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
E2D11: Which of the following data are used by the APRS network to communicate your location?
Polar coordinates
Time and frequency
Radio direction finding LOPs
Latitude and longitude
E2E06: What is the most common data rate used for HF packet communications?
48 baud
110 baud
300 baud
1200 baud
E3A06: What frequency range would you normally tune to find EME signals in the 2 meter band?
144.000 - 144.001 MHz
144.000 - 144.100 MHz
144.100 - 144.300 MHz
145.000 - 145.100 MHz
E3B09: At what time of day is gray-line propagation most likely to occur?
At sunrise and sunset
When the Sun is directly above the location of the transmitting station
When the Sun is directly overhead at the middle of the communications path between the two stations
When the Sun is directly above the location of the receiving station
E3C02: What is the cause of Aurora activity?
The interaction between the solar wind and the Van Allen belt
A low sunspot level combined with tropospheric ducting
The interaction of charged particles from the Sun with the Earth's magnetic field and the ionosphere
Meteor showers concentrated in the northern latitudes
E4A12: Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?
Use high quality double shielded coaxial cables to reduce signal losses
Attenuate the transmitter output going to the spectrum analyzer
Match the antenna to the load
All of these choices are correct
E4B15: Which of the following can be used as a relative measurement of the Q for a series-tuned circuit?
The inductance to capacitance ratio
The frequency shift
The bandwidth of the circuit's frequency response
The resonant frequency of the circuit
E4C02: Which of the following portions of a receiver can be effective in eliminating image signal interference?
A front-end filter or pre-selector
A narrow IF filter
A notch filter
A properly adjusted product detector
E4D01: What is meant by the blocking dynamic range of a receiver?
The difference in dB between the noise floor and thelevel of an incoming signal which will cause 1 dB of gain compression
The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
The difference in dB between the noise floor and the third order intercept point
The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
E4E09: What undesirable effect can occur when using an IF noise blanker?
Received audio in the speech range might have an echo effect
The audio frequency bandwidth of the received signal might be compressed
Nearby signals may appear to be excessively wide even if they meet emission standards
FM signals can no longer be demodulated
E5A08: What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?
The voltage leads the current by 90 degrees
The current leads the voltage by 90 degrees
The voltage and current are in phase
The voltage and current are 180 degrees out of phase
E5B04: What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors, all in parallel?
55 seconds
110 seconds
440 seconds
220 seconds
E5C21: Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?
Point 1
Point 3
Point 7
Point 8
E5D05: Which of the following creates a magnetic field?
Potential differences between two points in space
Electric current
A charged capacitor
A battery
E6A14: How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?
They are both low impedance
An FET has low input impedance; a bipolar transistor has high input impedance
An FET has high input impedance; a bipolar transistor has low input impedance
They are both high impedance
E6B07: What is the failure mechanism when a junction diode fails due to excessive current?
Excessive inverse voltage
Excessive junction temperature
Insufficient forward voltage
Charge carrier depletion
E6C01: What is the recommended power supply voltage for TTL series integrated circuits?
12 volts
1.5 volts
5 volts
13.6 volts
E6D08: What is one important reason for using powdered-iron toroids rather than ferrite toroids in an inductor?
Powdered-iron toroids generally have greater initial permeability
Powdered-iron toroids generally maintain their characteristics at higher currents
Powdered-iron toroids generally require fewer turns to produce a given inductance value
Powdered-iron toroids have higher power handling capacity
E6E05: Which of the following noise figure values is typical of a low-noise UHF preamplifier?
2 dB
-10 dB
44 dBm
-20 dBm
E6F05: Which of the following describes an optical shaft encoder?
A device which detects rotation of a control by interrupting a light source with a patterned wheel
A device which measures the strength a beam of light using analog to digital conversion
A digital encryption device often used to encrypt spacecraft control signals
A device for generating RTTY signals by means of a rotating light source.
E7A15: What is a D flip-flop?
A flip-flop whose output takes on the state of the D input when the clock signal transitions from low to high
A differential class D amplifier used as a flip-flop circuit
A dynamic memory storage element
A flip-flop whose output is capable of both positive and negative voltage excursions
E7B09: Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a pi-network output circuit?
The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
The tuning capacitor is adjusted for minimum plate current, while the loading capacitor is adjusted for maximum permissible plate current
E7C13: What is one advantage of a Pi matching network over an L matching network consisting of a single inductor and a single capacitor?
The Q of Pi networks can be varied depending on the component values chosen
L networks cannot perform impedance transformation
Pi networks have fewer components
Pi networks are designed for balanced input and output
E7D02: 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 control device's duty cycle is controlled to produce a constant average output voltage
It gives a ramp voltage at its output
E7E09: What occurs when an excessive amount of signal energy reaches a mixer circuit?
Spurious mixer products are generated
Mixer blanking occurs
Automatic limiting occurs
A beat frequency is generated
E7F01: What is the purpose of a prescaler circuit?
It converts the output of a JK flip flop to that of an RS flip-flop
It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
It prevents oscillation in a low-frequency counter circuit
It divides a higher frequency signal so a low-frequency counter can display the input frequency
E7G01: What primarily determines the gain and frequency characteristics of an op-amp RC active filter?
The values of capacitors and resistors built into the op-amp
The values of capacitors and resistors external to the op-amp
The input voltage and frequency of the op-amp's DC power supply
The output voltage and smoothness of the op-amp's DC power supply
E7H04: How is positive feedback supplied in a Colpitts oscillator?
Through a tapped coil
Through link coupling
Through a capacitive divider
Through a neutralizing capacitor
E8A09: What type of waveform is produced by human speech?
Sinusoidal
Logarithmic
Irregular
Trapezoidal
E8B11: Which of the following describes frequency division multiplexing?
The transmitted signal jumps from band to band at a predetermined rate
Two or more information streams are merged into a "baseband", which then modulates the transmitter
The transmitted signal is divided into packets of information
Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
E8C06: What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?
0.1 Hz
0.3 kHz
0.5 kHz
1.0 kHz
E8D04: What is the PEP output of a transmitter that develops a peak voltage of 30 volts into a 50-ohm load?
4.5 watts
9 watts
16 watts
18 watts
E9A03: Which of the following antennas has no gain in any direction?
Quarter-wave vertical
Yagi
Half-wave dipole
Isotropic antenna
E9B02: In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?
36 dB
18 dB
24 dB
14 dB
E9C13: What is the main effect of placing a vertical antenna over an imperfect ground?
It causes increased SWR
It changes the impedance angle of the matching network
It reduces low-angle radiation
It reduces losses in the radiating portion of the antenna
E9D04: Why is it desirable for a ground-mounted satellite communications antenna system to be able to move in both azimuth and elevation?
In order to track the satellite as it orbits the Earth
So the antenna can be pointed away from interfering signals
So the antenna can be positioned to cancel the effects of Faraday rotation
To rotate antenna polarization to match that of the satellite
E9E04: 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 to prevent the radiation of harmonics
To transform the antenna impedance to a higher value
E9F09: 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
E9G03: Which of the following is often determined using a Smith chart?
Beam headings and radiation patterns
Satellite azimuth and elevation bearings
Impedance and SWR values in transmission lines
Trigonometric functions
E9H03: What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2-dB feed line loss, 2.8-dB duplexer loss, 1.2-dB circulator loss and 7-dBi antenna gain?
159 watts
252 watts
632 watts
63.2 watts
