- How the GCT2 Exam Is Built
- Foundation Domains: Safety, Principles and Tools
- Radio and RF Domains
- Infrastructure Domains: Power, Antennas and Sites
- Network and Transport Domains
- All 13 Domains at a Glance
- Sequencing Your Prep Around the Domains
- Registration, Fees and Retake Mechanics
- Where These Domains Show Up on the Job
- Frequently Asked Questions
- The ETA International GCT2 exam covers 13 competency areas, from Safety through Physical Plant and Site procedures.
- The written exam has 100 questions in 2 hours, and the passing score is 75%.
- ETA's competency document lists all 13 domains but publishes no percentage weightings, so study every area.
- Eligibility requires a current GCT1 or Associate CET (CETa); no hands-on assessment is required.
How the GCT2 Exam Is Built
The General Communications Technician - Level 2 (GCT2) is a journeyman-level credential from ETA International. It sits above the GCT1 in ETA's communications track and tests whether a working technician can handle the broader systems knowledge that field and shop work demand. The exam is a single written knowledge test: 100 questions, two hours, and a 75% passing score. There is no hands-on component, so every skill is measured through questions rather than a bench practical.
The scope comes from ETA's published General Communications Technician - Level 2 (GCT2) Competency Requirements document, which lists 13 competency headings. That document does not assign percentage weightings to those headings. This matters for your preparation: you cannot safely skip a domain on the assumption that it is lightly tested. Any article claiming to know exact per-domain question counts is guessing, and this one will not.
If you are still confirming whether you qualify to sit for the exam, read the GCT2 requirements guide before going further. For the bigger picture of how this credential fits into a career path, the overview of GCT2 certification covers the basics.
Foundation Domains: Safety, Principles and Tools
The first four domains form the base that everything else rests on. They are also the areas where a GCT1 or CETa holder will feel most at home, though the GCT2 pushes deeper into application.
Domain 1: Safety
Communications work puts technicians near energized equipment, elevated structures, RF energy and confined or exposed sites. Expect the exam to test whether you recognize hazards and apply sound practice rather than recite regulations from memory.
- Electrical shock and grounding hazards around power and communications equipment
- RF exposure awareness near transmitting antennas and transmission lines
- Tower and elevated-work safety concepts, including personal protective practices
- Safe handling of batteries, tools and test equipment
Domain 2: Electronic and Electrical Principles
This is the theory layer. Questions here reward fluency with how voltage, current, resistance, reactance and impedance behave, because later domains lean on these ideas constantly.
- Ohm's law and power relationships in series and parallel circuits
- AC concepts, reactance, impedance and resonance
- Decibel relationships and signal gain or loss
- Basic semiconductor behavior and common component functions
Because scratch paper and a non-programmable scientific calculator are permitted, practice your calculations on exactly that kind of calculator before test day. Note that GCT2 is not on ETA's Common Formulas Sheet eligibility list, so plan to carry the key formulas in your head instead of expecting a reference sheet.
Domain 4: Tools, Methods and Test Equipment
This domain tests whether you know which instrument answers which question, and how to interpret what it shows. Since there is no practical exam, the written test checks your measurement judgment instead.
- Multimeters, oscilloscopes, spectrum analyzers and power meters: when each is appropriate
- Interpreting readings and recognizing the signs of a measurement error
- Proper test setup, calibration awareness and instrument limitations
Radio and RF Domains
Domains 3 and 8 form the radio core of the exam. They overlap, so study them as a pair: one frames the system, the other drills into how the equipment actually operates.
Domain 3: Fundamentals of Radio Systems
This domain covers how radio systems are structured and why they behave as they do. ETA recommends prior RF experience for GCT2 candidates, and this is where that experience pays off.
- Frequency, wavelength and propagation concepts
- Modulation types and why a system uses one over another
- Basic transmitter and receiver block structure
- Noise, interference and link-quality concepts
Domain 8: Operating Principles of Radio and Electronic Communications Equipment
Where Domain 3 is conceptual, this domain is equipment-focused. Expect questions about how specific stages and devices work and what symptoms point to specific faults.
- Stage-by-stage operation of transmitters, receivers and transceivers
- Oscillators, mixers, amplifiers and filters in practical equipment
- Reading functional descriptions and tracing a signal path
- Symptom-based reasoning about where a fault likely sits
Infrastructure Domains: Power, Antennas and Sites
Several domains cover the physical systems around the radio itself. These are the areas where field technicians often outperform bench-only candidates, because the questions reflect real installation and maintenance conditions.
Domain 5: Connectorization
Connectors are small, but poor termination causes a large share of real-world communications faults. The exam expects you to know connector families, their uses and the right way to install them.
- Coaxial, RF and data connector types and where each is used
- Termination practices and common installation errors
- Impedance continuity and the effect of a bad connection on loss and reflections
- Weatherproofing and strain-relief concepts
Domain 6: Power Systems
Communications sites live or die by their power. This domain covers how power is supplied, conditioned, backed up and protected.
- AC and DC power distribution at communications facilities
- Battery systems, charging and backup concepts
- Surge protection, grounding and bonding fundamentals
- Power-related troubleshooting at the equipment and site level
Domain 7: Antennas, Transmission Lines and Towers
This is one of the densest domains for calculation and applied knowledge. It ties directly back to Domain 2 and Domain 3.
- Antenna types, gain, polarization and radiation patterns
- Transmission line characteristics, standing wave ratio and loss
- Matching concepts and what a poor match does to a system
- Tower structure basics and how they connect to the safety domain
Domain 13: Physical Plant and Site Procedures
The last domain addresses the site as a whole: layout, environmental control, documentation and routine procedures.
- Equipment room and shelter organization and environmental considerations
- Cable routing, labeling and documentation practices
- Site access, inspection and maintenance routines
- Public-safety best practices, which ETA recommends candidates understand
Network and Transport Domains
The remaining domains cover how information moves, from digital networks to fiber, telephony and satellite links. Candidates from a pure radio background often find these the steepest part of the climb.
Domain 9: Networks - Serial Data, Internet Protocol (IP) to Wireless
The scope of this heading runs from simple serial links up through IP networking and wireless networks. Think of it as the bridge between traditional communications and modern data systems.
- Serial data interfaces and framing concepts
- IP addressing, subnetting basics and common network devices
- Wireless network concepts and the factors that affect link performance
- Basic network troubleshooting logic
Domain 10: Fiber Optic Systems
Fiber questions test both the physics of light transmission and practical handling and testing.
- Single-mode versus multimode fiber and typical applications
- Loss mechanisms, splicing and connector concepts
- Test methods such as power measurement and reflection-based testing
- Safe handling of fiber and the light sources used with it
Domain 11: Telephony
Telephony covers voice systems, from traditional concepts through the way voice is carried today.
- Core telephone system concepts and signaling ideas
- Analog and digital voice transport
- How voice systems interconnect with data networks
Domain 12: Satellite Communications Concepts
The heading says "concepts," and that is the right expectation: the exam tests how satellite links work and what limits them, not detailed earth-station design.
- Uplink, downlink and orbital basics
- Link budget ideas, path loss and rain or atmospheric effects
- Typical ground-equipment components and their roles
All 13 Domains at a Glance
Use this table as a checklist. Because ETA publishes no weightings, the "Study angle" column reflects how each domain typically connects to others, not how many questions it carries.
| Domain | Name | Study angle |
|---|---|---|
| 1 | Safety | Hazard recognition; links to towers, RF and power |
| 2 | Electronic and Electrical Principles | Theory and calculations underpinning every other domain |
| 3 | Fundamentals of Radio Systems | Concepts; pair with Domain 8 |
| 4 | Tools, Methods and Test Equipment | Choosing and interpreting instruments |
| 5 | Connectorization | Types, termination and fault effects |
| 6 | Power Systems | Distribution, backup, grounding |
| 7 | Antennas, Transmission Lines and Towers | Applied calculation; links to Domains 2 and 3 |
| 8 | Operating Principles of Radio and Electronic Communications Equipment | Equipment-level operation and fault reasoning |
| 9 | Networks - Serial Data, Internet Protocol (IP) to Wireless | Serial to IP to wireless; often the steepest for radio-only candidates |
| 10 | Fiber Optic Systems | Physics plus handling and testing |
| 11 | Telephony | Voice systems and their data interconnection |
| 12 | Satellite Communications Concepts | Link concepts and limiting factors |
| 13 | Physical Plant and Site procedures | Site layout, documentation, routine procedures |
For a compact version you can review in the final days, the GCT2 cheat sheet condenses the must-know facts into one page. For help gauging where the exam stands in difficulty, see how hard the GCT2 exam is.
Sequencing Your Prep Around the Domains
Rather than a generic schedule, order your study by dependency: later domains reuse earlier ones. The plan below is a suggested sequence and not a requirement; compress or stretch it to fit your experience.
Foundations: Domains 1, 2 and 4
- Refresh Ohm's law, AC theory, impedance and decibels with your permitted calculator
- Review safety hazards and instrument selection
Radio core: Domains 3 and 8
- Study them together, tracing a signal from transmitter to receiver
- Practice symptom-to-fault reasoning
Physical systems: Domains 5, 6, 7 and 13
- Work antenna and transmission-line calculations
- Cover connectors, power backup, grounding and site procedures
Transport and review: Domains 9 through 12
- Give extra time to networking if your background is radio-only
- Finish with full-length timed practice across all 13 domains
The GCT2 study guide expands on how to structure your sessions, and the GCT2 practice test site lets you drill questions by topic so you can find weak domains quickly.
Registration, Fees and Retake Mechanics
Knowing the logistics keeps administrative surprises from derailing a well-prepared candidate.
- Eligibility: a current GCT1 or Associate CET (CETa) is required.
- Experience requirement: ETA's 2026 GCT2 training notice specifies two years of electronics experience, gained through field experience, trade school or college, as a journeyman program requirement. Certification issuance may wait until that requirement is met.
- Fee: USD 105. A two-hour remotely proctored exam adds USD 16. You may see a USD 100 figure on the ETA Press listing; this article follows ETA's main certification page and 2026 training notice, both of which state USD 105. Confirm the current figure when you register. The GCT2 certification cost breakdown covers the full picture.
- Delivery: administered through ETA Certification Administrators using Trapeza online testing or paper and pencil, with ExamRoom.AI providing remote proctoring for non-hands-on exams.
- Test day: photo ID is required; scratch paper and a non-programmable scientific calculator are permitted.
- Retake: one free retake is available after a 30-day wait and within one year of the initial examination. Remote proctoring charges remain payable.
Scoring details are covered in the GCT2 passing score guide, and scheduling specifics in the GCT2 exam dates guide. If you want to know what the numbers say about outcomes, note that no issuer-wide GCT2 pass rate was found in the public sources reviewed; the GCT2 pass rate article explains what can and cannot be said.
Keeping the Credential Active
The certification term is four years. General maintenance requires the maintenance form, 10 continuing-education hours per year (40 over four years) or employer verification, and USD 25 per year (USD 100 per four-year cycle). Requirements may be submitted during the cycle, though ETA recommends annual submission.
Where These Domains Show Up on the Job
The breadth of the 13 domains mirrors the breadth of the work. A GCT2 holder is expected to be comfortable across radio, power, antenna systems, networking and site operations, which is why the credential suits roles that touch the whole communications stack rather than a single narrow task.
- Two-way radio and wireless service shops: Domains 3, 7 and 8 dominate daily work, with Domain 5 connectorization close behind.
- Tower and site service companies: Domains 1, 6, 7 and 13 define the job, with safety underpinning everything.
- Public-safety and utility communications teams: Site procedures, power backup and radio systems matter most, and ETA's recommendation of public-safety best practices points here.
- Network and fiber installers: Domains 9 and 10 carry the most weight, with connectorization and test equipment skills transferring directly.
For a look at job titles and earning potential, see the GCT2 jobs overview and the GCT2 salary guide. If you are weighing the investment, the GCT2 ROI analysis takes you through the tradeoffs.
Key Takeaway
Treat the 13 domains as one connected system, not 13 separate subjects. Theory in Domain 2 powers the radio and antenna domains, safety in Domain 1 touches nearly every physical domain, and site procedures in Domain 13 tie it all together. Study the links, not just the lists.
Frequently Asked Questions
ETA International's GCT2 competency requirements list 13 domains, running from Safety through Physical Plant and Site procedures. The exam is a 100-question written test with a two-hour limit and a 75% passing score.
ETA's competency document names all 13 headings but publishes no percentage weightings. Because you cannot tell how heavily any one area is tested, prepare across all 13 and spend extra time on your weakest areas.
No. The GCT2 is a written knowledge examination only. Skills such as test equipment use and connectorization are assessed through questions, so you need to understand procedures and interpretation well enough to answer them on paper or screen.
You need a current GCT1 or Associate CET (CETa). ETA's 2026 training notice also specifies two years of electronics experience, from the field, trade school or college, and certification issuance may wait until that is met. See the requirements guide for details.
One free retake is available after a 30-day wait and within one year of your first attempt. Any remote proctoring charges remain payable. Use the wait to review the domains where you were weakest and retest with timed practice questions.