Ham Radio Technician Flashcards: 90 Core Concepts for 2026-2030
Review 90 core concepts for the 2026–2030 U.S. Technician Class exam across all ten NCVEC subelements.
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Prepare for the U.S. Technician Class (Element 2) exam pool in effect from July 1, 2026, through June 30, 2030. These 90 core-concept flashcards use one-target prompts, direct answers, and brief explanations across all ten official NCVEC subelements.
This compact deck complements—not replaces—the full 409-question pool, randomized 35-question practice exams, and the three official diagrams. It does not reproduce the official multiple-choice wording, choices, distractors, or answer letters, and it does not claim full-pool coverage.
Facts were checked against the corrected February 19, 2026 NCVEC pool and current 47 CFR Part 97. Card wording and explanations are original. This independent study resource is not affiliated with or endorsed by NCVEC, the FCC, or any examination team. Consult the official pool at https://ncvec.org/index.php/2026-2030-technician-question-pool.
การ์ดในเด็คนี้
การ์ด 1
คำถาม
Which component is commonly used as an adjustable volume control?
คำตอบ
A potentiometer. It is a variable resistor with a movable contact.
การ์ด 2
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Which U.S. agency regulates and enforces the Amateur Radio Service rules?
คำตอบ
The Federal Communications Commission (FCC). It administers the rules that govern U.S. amateur stations.
การ์ด 3
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Which common voice mode uses less bandwidth: SSB or FM?
คำตอบ
SSB uses less bandwidth. This makes it well suited to crowded HF spectrum.
การ์ด 4
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What determines a radio wave’s polarization?
คำตอบ
The orientation of its electric field.
การ์ด 5
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What power-supply rating is typical for a 50-watt mobile FM transceiver?
คำตอบ
About 13.8 volts at 12 amperes. The current rating must cover the radio’s transmit demand.
การ์ด 6
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What is an amateur band plan?
คำตอบ
A voluntary guide for using different modes and activities within a band. It supplements—not replaces—FCC frequency privileges.
การ์ด 7
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How fast does a radio wave travel through free space?
คำตอบ
At the speed of light. Radio waves are electromagnetic waves.
การ์ด 8
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What is a fuse designed to do during an electrical overload?
คำตอบ
Open the circuit and remove power. It protects wiring and equipment from excessive current.
การ์ด 9
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What electrical quantity causes electrons to flow in a circuit?
คำตอบ
Voltage, or electrical potential difference. Current is the resulting flow of charge.
การ์ด 10
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When the station licensee and control operator are different people, who is responsible for proper station operation?
คำตอบ
Both are equally responsible. The station licensee and the control operator share responsibility for compliance.
การ์ด 11
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Which two major radio functions are combined inside a transceiver?
คำตอบ
A transmitter and a receiver. Both functions are combined in one unit.
การ์ด 12
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Which component stores energy in an electric field?
คำตอบ
A capacitor.
การ์ด 13
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What is the defining radiation-pattern advantage of a beam antenna?
คำตอบ
It concentrates radiation in one direction.
การ์ด 14
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What bandwidth is typical for an SSB voice signal?
คำตอบ
About 3 kHz.
การ์ด 15
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What is a clear way to begin a voice CQ call?
คำตอบ
Say “CQ” a few times, then “this is” and your call sign; pause and listen before repeating.
การ์ด 16
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Where does an RF power meter belong when measuring transmitter output to an antenna?
คำตอบ
In the feed line between the transmitter and the antenna.
การ์ด 17
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How often must an amateur station identify during a communication?
คำตอบ
At least every 10 minutes and at the end of the communication. A tactical identifier does not replace the assigned call sign.
การ์ด 18
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What unit measures electric current?
คำตอบ
The ampere (amp).
การ์ด 19
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Where should a fuse or circuit breaker go in a 120-volt AC circuit?
คำตอบ
In series with the hot conductor only. Do not put the protective device only in the neutral conductor.
การ์ด 20
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How does wavelength change when frequency increases?
คำตอบ
Wavelength decreases. Frequency and wavelength are inversely related when propagation speed is fixed.
การ์ด 21
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What does receiver sensitivity describe?
คำตอบ
The ability to detect weak signals. Better sensitivity means a weaker usable signal can be received.
การ์ด 22
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Which component stores energy in a magnetic field?
คำตอบ
An inductor.
การ์ด 23
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What does antenna gain describe?
คำตอบ
Signal-strength improvement in a chosen direction compared with a reference antenna. Gain redistributes radiation rather than creating transmitter power.
การ์ด 24
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What 10-meter frequency range gives a Technician voice privileges?
คำตอบ
28.300 to 28.500 MHz. This is the Technician phone segment on 10 meters.
การ์ด 25
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What does simplex operation mean?
คำตอบ
Both stations transmit and receive on the same frequency. No repeater frequency pair is involved.
การ์ด 26
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What bandwidth is typical for a VHF repeater FM voice signal?
คำตอบ
About 10 to 15 kHz.
การ์ด 27
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How many milliamperes are in 1.5 amperes?
คำตอบ
1,500 milliamperes. Multiply amperes by 1,000.
การ์ด 28
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What conductor is preferred for RF bonding between station equipment?
คำตอบ
Flat copper strap.
การ์ด 29
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What hazard can rapid charging or discharging create in an unprotected battery?
คำตอบ
Overheating or out-gassing. Use the battery’s specified protection and charge limits.
การ์ด 30
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Which semiconductor component normally allows current in only one direction?
คำตอบ
A diode.
การ์ด 31
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When may a newly licensed amateur first transmit?
คำตอบ
After the license grant appears in the FCC license database. Passing the exam alone does not authorize transmission.
การ์ด 32
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What does receiver selectivity describe?
คำตอบ
The ability to separate a desired signal from signals on nearby frequencies.
การ์ด 33
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What repeater offset is commonly used on the 2-meter band?
คำตอบ
Plus or minus 600 kHz. The sign depends on the repeater’s input/output pair.
การ์ด 34
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What shortcut estimates wavelength in meters from frequency in megahertz?
คำตอบ
Divide 300 by the frequency in MHz.
wavelength (m) ≈ 300 / frequency (MHz)การ์ด 35
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What happens to a dipole’s resonant frequency when the antenna is shortened?
คำตอบ
The resonant frequency increases. A shorter dipole resonates at a shorter wavelength and therefore a higher frequency.
การ์ด 36
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Which electrical property describes energy storage in an electric field?
คำตอบ
Capacitance. Its unit is the farad.
การ์ด 37
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What is Doppler shift?
คำตอบ
A change in observed frequency caused by relative motion between transmitter and receiver. Satellite operators compensate for it as the spacecraft passes.
การ์ด 38
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What should an antenna installer do about nearby overhead electrical wires?
คำตอบ
Locate them first and stay clear of them. This is an installation-safety rule, not an RF operating technique.
การ์ด 39
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Where should a mobile transceiver’s negative power return connect in a vehicle?
คำตอบ
At the 12-volt battery’s chassis-ground connection. Follow the radio and vehicle installation instructions when making the connection.
การ์ด 40
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Which amateur transmissions may use deliberately obscured message content?
คำตอบ
Commands to space stations or radio-controlled models. Ordinary amateur messages may not be encoded to hide their meaning.
การ์ด 41
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Which semiconductor component can act as an electronic switch?
คำตอบ
A transistor. It can control a larger current with a smaller input signal.
การ์ด 42
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What repeater offset is commonly used on the 70-centimeter band?
คำตอบ
Plus or minus 5 MHz.
การ์ด 43
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What simple device can suppress RF feedback traveling on a microphone cable?
คำตอบ
A ferrite choke. It adds impedance to unwanted common-mode RF current on the cable.
การ์ด 44
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What does a loading coil do in a shortened antenna?
คำตอบ
It electrically lengthens the antenna. The added inductive reactance helps a physically short radiator resonate lower.
การ์ด 45
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Which electrical property describes energy storage in a magnetic field?
คำตอบ
Inductance. Its unit is the henry.
การ์ด 46
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Which polarization is normally used for long-distance VHF/UHF CW and SSB contacts?
คำตอบ
Horizontal polarization.
การ์ด 47
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What is the maximum transmitter power in the HF segments available to a Technician?
คำตอบ
200 watts PEP. That ceiling applies to the Technician HF segments, including 28.0–28.5 MHz.
การ์ด 48
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How much clearance should a new antenna have from power wires?
คำตอบ
Enough that no part of the antenna can come within 10 feet of the wires if it falls.
การ์ด 49
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About how long does a low-Earth-orbit amateur satellite take to circle Earth?
คำตอบ
About 100 minutes.
การ์ด 50
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What happens when an SSB transmitter’s microphone gain is set too high?
คำตอบ
The transmitted audio becomes distorted.
การ์ด 51
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What does a CTCSS tone do in repeater operation?
คำตอบ
It provides a subaudible access tone that can open the repeater receiver. It does not encrypt the conversation.
การ์ด 52
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What does a schematic diagram show?
คำตอบ
Electrical connections using standardized component symbols. It describes circuit function, not physical placement.
การ์ด 53
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What formula gives DC electrical power from voltage and current?
คำตอบ
P = E × I. For example, 12 volts at 2 amperes is 24 watts.การ์ด 54
คำถาม
Where is a half-wave dipole’s radiation strongest?
คำตอบ
Broadside to the wire. Radiation is weakest off the ends.
การ์ด 55
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How long is a normal U.S. amateur radio license term?
คำตอบ
10 years. Renewal is required to continue operating after the term expires.
การ์ด 56
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What load should replace an antenna for transmitter tests that should not radiate a signal?
คำตอบ
A dummy load. It absorbs RF power while presenting a suitable impedance to the transmitter.
การ์ด 57
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What is a proper grounding arrangement for a tower?
คำตอบ
Use a separate eight-foot ground rod at each tower leg, bonded to the tower and to the other rods. Follow applicable electrical codes and local requirements.
การ์ด 58
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Why can a VHF signal change sharply when an antenna moves only a few feet?
คำตอบ
Multipath propagation. Reflected signal paths can add or cancel at nearby points.
การ์ด 59
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How can an operator judge suitable uplink power through a linear amateur satellite transponder?
คำตอบ
Keep the received downlink signal about as strong as the satellite beacon.
การ์ด 60
คำถาม
What is a DMR color code?
คำตอบ
A repeater access code used by DMR systems. It is not a description of display color or signal quality.
การ์ด 61
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What does a power-supply rectifier do?
คำตอบ
It changes AC into a varying or pulsating DC voltage. Filtering can then smooth that voltage.
การ์ด 62
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Which receiver control corrects a returned SSB voice that sounds too high or too low in pitch?
คำตอบ
The RIT, also called the clarifier. It shifts the receive tuning enough to restore natural voice pitch.
การ์ด 63
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When may a U.S. amateur station normally relay a third party’s message to a station in another country?
คำตอบ
When that country has a third-party communications arrangement with the United States. Emergency or disaster-relief traffic has a separate exception.
การ์ด 64
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What form of Ohm’s law gives current from voltage and resistance?
คำตอบ
I = E / R. For example, 12 volts across 6 ohms produces 2 amperes.การ์ด 65
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How does coaxial-cable loss change as signal frequency increases?
คำตอบ
Loss increases. The same cable run usually wastes more power at higher frequencies.
การ์ด 66
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What does a 4:1 SWR indicate?
คำตอบ
A serious impedance mismatch. It is much worse than the near-1:1 match a transmitter normally prefers.
การ์ด 67
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Are amateur radio signals ionizing or non-ionizing radiation?
คำตอบ
Non-ionizing radiation. RF exposure still requires compliance with FCC limits.
การ์ด 68
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What is the general maximum transmitter power for Technician operation above 30 MHz?
คำตอบ
1,500 watts PEP, unless a narrower rule sets a lower limit. In actual operation, Part 97 also requires using only the power needed for the communication.
การ์ด 69
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What does a DMR talkgroup identify?
คำตอบ
A logical group of users or traffic on a DMR system. It routes a transmission to the intended group.
การ์ด 70
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What is a Maidenhead grid locator?
คำตอบ
A letter-and-number designator for a geographic area. Operators exchange it to describe station location compactly.
การ์ด 71
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Which component uses an electrical control signal to open or close contacts in another circuit?
คำตอบ
A relay. It is an electrically controlled switch.
การ์ด 72
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Which electrical quantity is the same through every component in a series circuit?
คำตอบ
Current. A series circuit has only one current path.
การ์ด 73
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Why is the VHF/UHF radio horizon usually a little farther than the visual horizon?
คำตอบ
The atmosphere refracts radio waves slightly. This modest bending extends the practical radio horizon.
การ์ด 74
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How should receiver filter bandwidth be set to reduce noise and nearby interference?
คำตอบ
Use the narrowest bandwidth that still passes the desired signal. Different modes need different practical widths.
การ์ด 75
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What is the main function of an antenna tuner?
คำตอบ
To match the antenna system’s impedance to the transceiver’s output impedance. It helps the transmitter see a suitable load.
การ์ด 76
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What does Part 97 say about deliberately disrupting another radio communication?
คำตอบ
Willful or malicious interference is prohibited. Frequency use is shared, not assigned exclusively to one station.
การ์ด 77
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How is a voltmeter connected to measure voltage across a component?
คำตอบ
In parallel with the component.
การ์ด 78
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Why does duty cycle matter in an RF exposure evaluation?
คำตอบ
It changes average exposure. A transmitter active for a smaller fraction of the averaging period contributes less average RF energy.
การ์ด 79
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What is the central job of a net control station?
คำตอบ
Call the net to order and direct participating stations. Net control organizes check-ins and traffic flow.
การ์ด 80
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Which electrical quantity is the same across every branch of a parallel circuit?
คำตอบ
Voltage. Each branch connects across the same two nodes.
การ์ด 81
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Which component can step 120-volt AC down to a lower AC voltage?
คำตอบ
A transformer.
การ์ด 82
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What does APRS commonly provide?
คำตอบ
Real-time tactical digital communication, including station positions shown on a map.
การ์ด 83
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When a DMR radio’s channels, repeater settings, contacts, and talkgroups are saved together, what is that data set called?
คำตอบ
A DMR code plug. It is the radio’s configuration data set.
การ์ด 84
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What does standing wave ratio measure in a feed line?
คำตอบ
How well the load impedance matches the feed line. An SWR near 1:1 indicates a close match.
การ์ด 85
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What can an operator do during the two-year filing grace period after an amateur license expires?
คำตอบ
Apply for renewal, but do not transmit until the license is renewed. The grace period preserves a renewal path, not operating privileges.
การ์ด 86
คำถาม
Which propagation mode can produce occasional strong 10-, 6-, and 2-meter contacts beyond the normal radio horizon?
คำตอบ
Sporadic E. It can briefly carry signals well beyond ordinary VHF line-of-sight range.
การ์ด 87
คำถาม
Do Part 97 rules stop applying during ARES, RACES, FEMA, or emergency operations?
คำตอบ
No. FCC amateur radio rules always apply. Emergency conditions may activate specific provisions, but they do not erase Part 97.
การ์ด 88
คำถาม
Who is responsible for keeping people below FCC RF exposure limits at an amateur station?
คำตอบ
The station licensee. This is a compliance responsibility; practical evaluations can use calculation, modeling, or calibrated measurement.
การ์ด 89
คำถาม
How is an ammeter connected to measure current in a circuit?
คำตอบ
In series with the circuit path.
การ์ด 90
คำถาม
What decibel change represents doubling transmitter power from 5 watts to 10 watts?
คำตอบ
About +3 dB. A 3 dB increase corresponds to roughly twice the power.
90 การ์ด
Ham Radio Technician Flashcards: 90 Core Concepts for 2026-2030
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