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2023 General pool
50 / 430 questions need explanations
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What is the purpose of an antenna tuner?
  • Reduce the SWR in the feed line to the antenna (32% chose this)
  • Reduce the power dissipation in the feedline to the antenna (10% chose this)
  • Increase power transfer from the transmitter to the feed line (19% chose this)
  • All these choices are correct (39% chose this)
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Which intermodulation products are closest to the original signal frequencies?
  • Second harmonics (46% chose this)
  • Even-order (10% chose this)
  • Odd-order (27% chose this)
  • Intercept point (17% chose this)
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Which of the following is an odd-order intermodulation product of frequencies F1 and F2?
  • 5F1-3F2 (16% chose this)
  • 3F1-F2 (18% chose this)
  • 2F1-F2 (25% chose this)
  • All these choices are correct (41% chose this)
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What is the term for the inverse of impedance?
  • Conductance (59% chose this)
  • Susceptance (2% chose this)
  • Reluctance (14% chose this)
  • Admittance (25% chose this)
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What does an FT8 signal report of +3 mean?
  • The signal is 3 times the noise level of an equivalent SSB signal (19% chose this)
  • The signal is S3 (weak signals) (8% chose this)
  • The signal-to-noise ratio is equivalent to +3dB in a 2.5 kHz bandwidth (33% chose this)
  • The signal is 3 dB over S9 (40% chose this)
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When operating a station in South America by remote control over the internet from the US, what regulations apply?
  • Those of both the remote station’s country and the FCC (37% chose this)
  • Those of the remote station’s country and the FCC’s third-party regulations (21% chose this)
  • Only those of the remote station’s country (26% chose this)
  • Only those of the FCC (16% chose this)
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What output is produced by a balanced modulator?
  • Frequency modulated RF (34% chose this)
  • Audio with equalized frequency response (26% chose this)
  • Audio extracted from the modulation signal (6% chose this)
  • Double-sideband modulated RF (34% chose this)
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What is a typical upper frequency limit for low SWR operation of 50-ohm BNC connectors?
  • 50 MHz (21% chose this)
  • 500 MHz (42% chose this)
  • 4 GHz (33% chose this)
  • 40 GHz (4% chose this)
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What happens when inductive and capacitive reactance are equal in a series LC circuit?
  • Resonance causes impedance to be very high (30% chose this)
  • Impedance is equal to the geometric mean of the inductance and capacitance (15% chose this)
  • Resonance causes impedance to be very low (34% chose this)
  • Impedance is equal to the arithmetic mean of the inductance and capacitance (21% chose this)
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What effect can strong signals from nearby transmitters have on an antenna analyzer?
  • Desensitization which can cause intermodulation products which interfere with impedance readings (2% chose this)
  • Received power that interferes with SWR readings (39% chose this)
  • Generation of harmonics which interfere with frequency readings (4% chose this)
  • All these choices are correct (56% chose this)
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Which is true of mesh network microwave nodes?
  • Having more nodes increases signal strengths (5% chose this)
  • If one node fails, a packet may still reach its target station via an alternate node (59% chose this)
  • Links between two nodes in a network may have different frequencies and bandwidths (24% chose this)
  • More nodes reduce overall microwave out of band interference (11% chose this)
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How is a product detector used?
  • Used in test gear to detect spurious mixing products (19% chose this)
  • Used in transmitter to perform frequency multiplication (9% chose this)
  • Used in an FM receiver to filter out unwanted sidebands (21% chose this)
  • Used in a single sideband receiver to extract the modulated signal (51% chose this)
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What is QPSK modulation?
  • Modulation using quasi-parallel to serial conversion to reduce bandwidth (7% chose this)
  • Modulation using quadra-pole sideband keying to generate spread spectrum signals (20% chose this)
  • Modulation using Fast Fourier Transforms to generate frequencies at the first, second, third, and fourth harmonics of the carrier frequency to improve noise immunity (22% chose this)
  • Modulation in which digital data is transmitted using 0-, 90-, 180- and 270-degrees phase shift to represent pairs of bits (52% chose this)
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What is the term for interference from a signal at twice the IF frequency from the desired signal?
  • Quadrature response (17% chose this)
  • Image response (48% chose this)
  • Mixer interference (22% chose this)
  • Intermediate interference (13% chose this)
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What occurs in an LC circuit at resonance?
  • Current and voltage are equal (30% chose this)
  • Resistance is cancelled (9% chose this)
  • The circuit radiates all its energy in the form of radio waves (11% chose this)
  • Inductive reactance and capacitive reactance cancel (49% chose this)
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Which of the following is good practice when choosing a transmitting frequency to answer a station calling CQ using FT8?
  • Always call on the station’s frequency (49% chose this)
  • Call on any frequency in the waterfall except the station’s frequency (0% chose this)
  • Find a clear frequency during the same time slot as the calling station (13% chose this)
  • Find a clear frequency during the alternate time slot to the calling station (39% chose this)
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What letter is used to represent reactance?
  • Z (30% chose this)
  • X (46% chose this)
  • B (5% chose this)
  • Y (20% chose this)
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When is an analog multimeter preferred to a digital multimeter?
  • When testing logic circuits (6% chose this)
  • When high precision is desired (22% chose this)
  • When measuring the frequency of an oscillator (28% chose this)
  • When adjusting circuits for maximum or minimum values (45% chose this)
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Which of the following is a way to determine current propagation on a desired band from your station?
  • Use a network of automated receiving stations on the internet to see where your transmissions are being received (45% chose this)
  • Check the A-index (6% chose this)
  • Send a series of dots and listen for echoes (8% chose this)
  • All these choices are correct (42% chose this)
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What is the purpose of delaying RF output after activating a transmitter’s keying line to an external amplifier?
  • To prevent key clicks on CW (7% chose this)
  • To prevent transient overmodulation (14% chose this)
  • To allow time for the amplifier to switch the antenna between the transceiver and the amplifier output (54% chose this)
  • To allow time for the amplifier power supply to reach operating level (25% chose this)
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How does a liquid crystal display compare to an LED display?
  • Higher contrast in high ambient lighting (62% chose this)
  • Wider dynamic range (6% chose this)
  • Higher power consumption (18% chose this)
  • Shorter lifetime (14% chose this)
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How often may RACES training drills and tests be routinely conducted without special authorization?
  • No more than 1 hour per month (16% chose this)
  • No more than 2 hours per month (18% chose this)
  • No more than 1 hour per week (47% chose this)
  • No more than 2 hours per week (19% chose this)
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When may third-party messages be transmitted via remote control?
  • Under any circumstances in which third party messages are permitted by FCC rules (46% chose this)
  • Under no circumstances except for emergencies (33% chose this)
  • Only when the message is intended for licensed radio amateurs (14% chose this)
  • Only when the message is intended for third parties in areas where licensing is controlled by the FCC (7% chose this)
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What procedure may be used by Volunteer Monitors to localize a station whose continuous carrier is holding a repeater on in their area?
  • Compare vertical and horizontal signal strengths on the input frequency (3% chose this)
  • Compare beam headings on the repeater input from their home locations with that of other Volunteer Monitors (48% chose this)
  • Compare signal strengths between the input and output of the repeater (7% chose this)
  • All these choices are correct (42% chose this)
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Which parameter affects receiver sensitivity?
  • Input amplifier gain (29% chose this)
  • Demodulator stage bandwidth (9% chose this)
  • Input amplifier noise figure (4% chose this)
  • All these choices are correct (59% chose this)
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What is the output voltage if an input signal is applied to the secondary winding of a 4:1 voltage step-down transformer instead of the primary winding?
  • The input voltage is multiplied by 4 (60% chose this)
  • The input voltage is divided by 4 (34% chose this)
  • Additional resistance must be added in series with the primary to prevent overload (3% chose this)
  • Additional resistance must be added in parallel with the secondary to prevent overload (2% chose this)
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Where should the station’s lightning protection ground system be located?
  • As close to the station equipment as possible (37% chose this)
  • Outside the building (61% chose this)
  • Next to the closest power pole (0% chose this)
  • Parallel to the water supply line (2% chose this)
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Which HF bands have segments exclusively allocated to Amateur Extra licensees?
  • All HF bands (28% chose this)
  • 80 meters, 40 meters, 20 meters, and 15 meters (34% chose this)
  • All HF bands except 160 meters and 10 meters (17% chose this)
  • 60 meters, 30 meters, 17 meters, and 12 meters (21% chose this)
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What action results from a failure to exchange information due to excessive transmission attempts when using an ARQ mode?
  • The checksum overflows (6% chose this)
  • The connection is dropped (69% chose this)
  • Packets will be routed incorrectly (19% chose this)
  • Encoding reverts to the default character set (6% chose this)
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Which of the following describes Winlink?
  • An amateur radio wireless network to send and receive email on the internet (26% chose this)
  • A form of Packet Radio (5% chose this)
  • A wireless network capable of both VHF and HF band operation (5% chose this)
  • All of the above (64% chose this)
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What is a link budget?
  • The financial costs associated with operating a radio link (10% chose this)
  • The sum of antenna gains minus system losses (18% chose this)
  • The sum of transmit power and antenna gains minus system losses as seen at the receiver (62% chose this)
  • The difference between transmit power and receiver sensitivity (10% chose this)
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What is VARA?
  • A low signal-to-noise digital mode used for EME (moonbounce) (7% chose this)
  • A digital protocol used with Winlink (68% chose this)
  • A radio direction finding system used on VHF and UHF (16% chose this)
  • DX spotting system using a network of software defined radios (9% chose this)
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Why are signal reports typically exchanged at the beginning of an HF contact?
  • To allow each station to operate according to conditions (68% chose this)
  • To be sure the contact will count for award programs (7% chose this)
  • To follow standard radiogram structure (12% chose this)
  • To allow each station to calibrate their frequency display (14% chose this)
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Which of the following is good amateur practice for net management?
  • Always use multiple sets of phonetics during check-in (4% chose this)
  • Have a backup frequency in case of interference or poor conditions (54% chose this)
  • Transmit the full net roster at the beginning of every session (8% chose this)
  • All these choices are correct (34% chose this)
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Which of these functions is performed by software in a software-defined radio (SDR)?
  • Filtering (10% chose this)
  • Detection (0% chose this)
  • Modulation (8% chose this)
  • All these choices are correct (82% chose this)
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Where should lightning arrestors be located?
  • Where the feed lines enter the building (67% chose this)
  • On the antenna, opposite the feed point (11% chose this)
  • In series with each ground lead (13% chose this)
  • At the closest power pole ground electrode (8% chose this)
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In an ARQ mode, what is meant by a NAK response to a transmitted packet?
  • Request retransmission of the packet (73% chose this)
  • Packet was received without error (13% chose this)
  • Receiving station connected and ready for transmissions (11% chose this)
  • Entire file received correctly (4% chose this)
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What is link margin?
  • The opposite of fade margin (4% chose this)
  • The difference between received power level and minimum required signal level at the input to the receiver (72% chose this)
  • Transmit power minus receiver sensitivity (9% chose this)
  • Receiver sensitivity plus 3 dB (16% chose this)
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What precaution should be taken when connecting a solar panel to a lithium iron phosphate battery?
  • Ground the solar panel outer metal framework (11% chose this)
  • Ensure the battery is placed terminals-up (3% chose this)
  • A series resistor must be in place (20% chose this)
  • The solar panel must have a charge controller (66% chose this)
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When operating a US station by remote control from outside the country, what license is required of the control operator?
  • A US operator/primary station license (51% chose this)
  • Only an appropriate US operator/primary license and a special remote station permit from the FCC (23% chose this)
  • Only a license from the foreign country, as long as the call sign includes identification of portable operation in the US (12% chose this)
  • A license from the foreign country and a special remote station permit from the FCC (13% chose this)
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On which HF and/or MF amateur bands are there portions where General class licensees cannot transmit?
  • 60 meters, 30 meters, 17 meters, and 12 meters (24% chose this)
  • 160 meters, 60 meters, 15 meters, and 12 meters (24% chose this)
  • 80 meters, 40 meters, 20 meters, and 15 meters (40% chose this)
  • 80 meters, 20 meters, 15 meters, and 10 meters (11% chose this)
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What must you do if your station fails to meet the FCC RF exposure exemption criteria?
  • Perform an RF Exposure Evaluation in accordance with FCC OET Bulletin 65 (74% chose this)
  • Contact the FCC for permission to transmit (2% chose this)
  • Perform an RF exposure evaluation in accordance with World Meteorological Organization guidelines (9% chose this)
  • Use an FCC-approved band-pass filter (16% chose this)
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Which of the following provide digital voice modes?
  • WSPR, MFSK16, and EasyPAL (6% chose this)
  • FT8, FT4, and FST4 (12% chose this)
  • Winlink, PACTOR II, and PACTOR III (14% chose this)
  • DMR, D-STAR, and SystemFusion (68% chose this)
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Which of the following is a common use of the dual-VFO feature on a transceiver?
  • To allow transmitting on two frequencies at once (11% chose this)
  • To permit full duplex operation -- that is, transmitting and receiving at the same time (8% chose this)
  • To transmit on one frequency and listen on another (74% chose this)
  • To improve frequency accuracy by allowing variable frequency output (VFO) operation (6% chose this)
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What is another name for a Winlink Remote Message Server?
  • Terminal Node Controller (21% chose this)
  • Gateway (73% chose this)
  • RJ-45 (3% chose this)
  • Printer/Server (3% chose this)
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What is meant by the term “critical frequency” at a given incidence angle?
  • The highest frequency which is refracted back to Earth (79% chose this)
  • The lowest frequency which is refracted back to Earth (8% chose this)
  • The frequency at which the signal-to-noise ratio approaches unity (11% chose this)
  • The frequency at which the signal-to-noise ratio is 6 dB (2% chose this)
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What is the primary purpose of an Amateur Radio Emergency Data Network (AREDN) mesh network?
  • To provide FM repeater coverage in remote areas (5% chose this)
  • To provide real time propagation data by monitoring amateur radio transmissions worldwide (16% chose this)
  • To provide high-speed data services during an emergency or community event (79% chose this)
  • To provide DX spotting reports to aid contesters and DXers (0% chose this)
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How much change in signal strength is typically represented by one S unit?
  • 6 dB (77% chose this)
  • 12 dB (11% chose this)
  • 15 dB (8% chose this)
  • 18 dB (5% chose this)
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What symptoms may result from other signals interfering with a PACTOR or VARA transmission?
  • Frequent retries or timeouts (2% chose this)
  • Long pauses in message transmission (0% chose this)
  • Failure to establish a connection between stations (12% chose this)
  • All these choices are correct (87% chose this)
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In what configuration are the individual cells in a solar panel connected together?
  • Series-parallel (85% chose this)
  • Shunt (5% chose this)
  • Bypass (2% chose this)
  • Full-wave bridge (9% chose this)
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