2025-11-29
Coaxial cables have quietly powered the world’s radio, satellite, broadcast, and data systems for nearly a century—yet they remain one of the most misunderstood components in modern electronics. Engineers know that the wrong coax cable can cripple RF performance, OEM factories know that attenuation can kill production yields, and trading companies feel the pressure when a buyer sends nothing but a photo and asks, “Can you make this?” In a world where so many options exist—RG series, LMR series, semi-rigid, micro coax—making the wrong choice means lost signal integrity, overheating, compliance failures, or costly redesigns.
The main types of coaxial cable include RG-series cables (such as RG6, RG59, RG58 and RG174), LMR low-loss cables, hardline coax, semi-rigid coax, semi-flexible coax, and micro-coax cables. Each type differs by impedance, frequency range, shielding, attenuation, diameter, and application suitability. The right coax cable depends on your project’s electrical requirements, environmental conditions, connector type, and installation constraints.
Behind every coax cable specification lies a real decision that impacts your system’s long-term reliability—voltage, impedance, EMI shielding, jacket material, OD tolerance, connector selection, and even bend radius. At Sino-Media, we see this daily. One engineer sends a full drawing with precise pin-outs, while another simply uploads a smartphone photo and asks, “Can you match this?” Both are valid needs—and both depend entirely on understanding coax cable types.
The story usually starts the same way: a buyer searching online for “types of coaxial cable.” The difference is what happens next. This article ensures that when the next buyer lands on your site, they stay, learn, trust, and eventually ask for a quote.
A coaxial cable works by transmitting high-frequency electrical signals through a central conductor surrounded by a dielectric layer, shielding, and an outer jacket. This layered structure allows the cable to carry RF, video, and data signals with minimal loss and excellent noise immunity. Impedance consistency (typically 50Ω or 75Ω) ensures stable signal flow, while shielding prevents external EMI from degrading performance.
A coaxial cable consists of four primary layers: the inner conductor, dielectric insulation, shielding, and outer jacket. These layers share a common center axis—hence the word co-axial. The conductor carries the signal, the dielectric maintains impedance and spacing accuracy, the shielding blocks external interference, and the jacket protects from heat, oil, UV, abrasion, or chemicals. Different industries demand different combinations: medical devices may require ultra-thin FEP jackets; outdoor antennas need UV-resistant PE; automotive often asks for halogen-free and flame-retardant materials.
The two most common impedances are 50Ω (RF, wireless, test equipment) and 75Ω (video, broadcast, set-top boxes). Impedance mismatch can cause reflection and severe signal loss. Engineers frequently approach Sino-Media asking why their system fails at high frequencies—only to discover they used the wrong impedance or mixed connectors like SMA (50Ω) with F-type (75Ω). Impedance must remain consistent across cable, connectors, and equipment.
Shielding types include braid, foil, double braid, and quad-shield. More coverage equals better EMI resistance but also increased diameter and stiffness. Wireless, radar, and industrial systems rely heavily on shielding effectiveness. Inconsistent braid coverage—not uncommon with low-cost alternatives—can introduce noise spikes. Sino-Media’s 100% inspection ensures stable braid density, especially for high-frequency RG and LMR assemblies.
Spec sheets typically list: OD, conductor gauge, dielectric constant, shielding type, impedance, attenuation values, bend radius, voltage rating, temperature range, flexibility, flame rating, UV resistance, and compliance certifications (UL, RoHS, REACH, PFAS). Buyers often come with a model number but no technical parameters; Sino-Media reverse-engineers it and provides accurate drawings within 30 minutes to 3 days.
The main coaxial cable types used today include RG-series cables (e.g., RG6, RG58, RG59, RG174), LMR low-loss RF cables, semi-rigid and semi-flexible coax for high-frequency precision applications, hardline coax for high-power communication systems, and micro-coax cables for compact electronic devices. These types differ in impedance, attenuation, flexibility, shielding construction, and suitable environments.
| RG Type | Impedance | OD (mm) | Attenuation @1 GHz (dB/m) | Flexibility | Typical Applications |
|---|---|---|---|---|---|
| RG6 | 75Ω | ~6.8 | ~0.22 | Medium | TV, satellite, broadband |
| RG59 | 75Ω | ~6.1 | ~0.30 | High | CCTV, analog video |
| RG58 | 50Ω | ~5.0 | ~0.50 | Medium | RF, radio, testing |
| RG174 | 50Ω | ~2.8 | ~1.20 | Very High | GPS, IoT, automotive, compact devices |
RG (Radio Guide) cables remain the most widely recognized family due to historical standardization and broad usage. Each RG number signals a unique combination of impedance, OD, and attenuation characteristics.
RG cables vary widely in dielectric material (PE, foam PE, PTFE), braid coverage, and jacket composition. Many engineers still use RG numbers as a quick shorthand, but actual construction differs significantly between manufacturers.
LMR cables offer improved shielding and lower attenuation for RF communication systems, including 4G/5G antennas, WiFi, GPS, IoT networks, and point-to-point links.
LMR cables achieve low loss through:
Common types include LMR-100, LMR-200, LMR-240, LMR-400, where the number roughly correlates with diameter. LMR cables are especially effective for longer RF runs where RG cable attenuation becomes excessive.
Semi-rigid coax uses a solid metal outer conductor—usually copper or aluminum—which allows the cable to retain its shape permanently once bent.
Key characteristics:
Semi-rigid cables are standard in aerospace, radar modules, laboratory instruments, and high-frequency communication hardware.
Semi-flexible coax provides a compromise between performance and ease of installation.
Compared with semi-rigid:
These cables often replace semi-rigid designs when the installation requires adjustments or when vibration tolerance is needed.
Hardline coax is characterized by very large diameter and extremely low attenuation, making it suitable for:
Hardline often incorporates air dielectric spacers and corrugated copper or aluminum shielding. Signal loss is far lower than RG or LMR cables but flexibility is minimal.
Micro-coax is used in space-constrained environments:
These cables often have OD values below 1 mm and require:
Micro-coax is typically selected when miniaturization and high-frequency transmission must coexist.
Coaxial cable applications vary: RG59 and RG6 for video and CCTV, RG58 and LMR cables for RF and wireless systems, micro-coax for compact electronics, semi-rigid for aerospace, and hardline for high-power broadcasting. Selecting the right cable depends on frequency range, distance, environment, connector type, and required flexibility.
| Application Field | Recommended Cable Types | Impedance | Key Considerations |
|---|---|---|---|
| RF / Wireless | RG58, RG174, LMR Series | 50Ω | Low loss, shielding, frequency range |
| CCTV / Video | RG59, RG6 | 75Ω | Long-distance video stability |
| Aerospace / Radar | Semi-Rigid, Semi-Flexible | 50Ω | High-frequency stability |
| Automotive | Micro-Coax, RG174 | 50Ω | Vibration, temperature |
| Medical Devices | Micro-Coax, PTFE-based | 50Ω/75Ω | High reliability, sterilization |
| Broadcasting | Hardline, LMR400 | 50Ω/75Ω | High power, low attenuation |
50Ω cables (RG58, RG174, LMR) dominate wireless applications, including WiFi, 4G/5G, LoRa, GPS, Bluetooth, and industrial RF. Shielding quality and frequency performance are essential—poor-quality coax can introduce dB losses that cripple antennas.
75Ω cables like RG59 and RG6 remain standard for HD CCTV and broadcast. Their low-loss characteristics enable long-distance video transmission. For digital broadcast (DVB, ATSC), engineers prioritize attenuation stability across temperature—a parameter Sino-Media tests during inspection.
These industries require temperature, vibration, and chemical resistance. Micro-coax and custom small-OD cables are common. Military often requests semi-rigid coax with strict tolerance and documentation (COC, COO, PFAS-free confirmation).
Trading companies often rely on Sino-Media to verify specifications because photos lack details. OEM factories care about price, lead time, and consistent quality. Engineers care about parameters; procurement cares about cost; R&D cares about feasibility.
Coaxial cable diameter and construction directly influence attenuation, flexibility, power handling, EMI shielding, and environmental resistance. Larger-diameter cables generally offer lower signal loss and higher power capacity, while smaller cables improve flexibility and fit compact spaces. Materials used in the dielectric, shielding, and jacket determine frequency range, thermal stability, and durability.
| Cable Type | OD (mm) | Frequency | Attenuation (dB/m) | Power Handling | Flexibility |
|---|---|---|---|---|---|
| RG174 | ~2.8 | 1 GHz | ~1.20 | Low | Very High |
| RG58 | ~5.0 | 1 GHz | ~0.50 | Medium | Medium |
| LMR-200 | ~5.0 | 1 GHz | ~0.23 | Medium-High | Medium |
| LMR-400 | ~10.3 | 1 GHz | ~0.07 | High | Low |
As OD increases, attenuation generally decreases. Larger cables support higher frequencies and longer distances because the conductor cross-sectional area increases and dielectric losses decrease.
Smaller ODs are useful but introduce limitations:
Engineers must weigh size constraints against acceptable loss budgets.
Smaller cables are more flexible, but bending affects impedance.
Foam dielectrics tend to deform more easily, requiring careful routing. PTFE dielectrics maintain shape better under mechanical stress.
Designers typically follow manufacturer bend-radius guidelines to avoid phase distortion.
| Dielectric Material | Dielectric Constant | Temp Rating | Loss Level | Typical Use Cases |
|---|---|---|---|---|
| Solid PE | ~2.3 | Moderate | Medium | CCTV, low RF |
| Foam PE | ~1.4–1.6 | Moderate | Lower | Broadband, LMR cables |
| PTFE | ~2.1 | High | Very Low | Microwave, aerospace, high-temp systems |
| Air/Spacers | ~1.0 | Varies | Lowest | High-power, hardline coax |
The dielectric determines impedance stability and high-frequency capability.
A lower dielectric constant generally improves high-frequency performance but may reduce mechanical stability.
| Shield Type | Coverage | EMI Protection | Flexibility | Typical Applications |
|---|---|---|---|---|
| Single Braid | Low | Basic | High | Low-frequency, general purpose |
| Double Braid | Medium | Good | Medium | RF equipment, industrial |
| Foil + Braid | High | Very Good | Medium-Low | GHz-range, broadcast |
| Quad-Shield | Very High | Excellent | Low | Dense RF environments, strong EMI zones |
Shielding materials affect both electrical behavior and durability.
Typical shielding types:
Higher shielding increases stiffness but improves return loss consistency.
The outer jacket defines durability and environmental compatibility.
Common jackets:
Material choice affects:
Selecting incorrect jacket material can cause early cable degradation even if electrical parameters match.
Micro-coax cables (<1.5 mm OD) balance size and performance, but with trade-offs:
However, micro-coax remains essential in imaging, sensing, and mobile electronics where space is the primary constraint.
Choosing the right coax cable requires matching impedance, frequency range, connector type, environment, and installation constraints. Custom assemblies often deliver better performance and reliability, especially when precise lengths, pin-outs, or specialty connectors are required.
Buyers should consider: frequency, distance, EMI, OD limits, flexibility, environment, connector type, compliance needs, and budget range.
Incorrect connector choice destroys performance. Sino-Media assists with CAD drawings, pin-out design, and ensuring perfect cable-to-connector pairing.
Custom assemblies ensure correct impedance, shielding, materials, lengths, and pin-outs. With Sino-Media’s no-MOQ policy and fast prototyping, even small projects are feasible.
Send your inquiry directly to us
