Understanding Coaxial Cable
Coaxial cable, widely used in various devices, is gaining popularity due to its exceptional sound quality and user-friendly nature. These cables ensure precise transmission of audio signals in digital format.
If you’re new to coaxial cables, let’s start with the basics. Grab a seat and join us on a journey to discover the important theories behind coaxial speaker cables.
What Exactly is a Coaxial Cable?
Back in 1880, an innovative English mathematician and engineer named Oliver Heaviside introduced the world to the marvel of coaxial cables, earning himself a patent.
Coaxial cables are electrical cables featuring a conductive core wrapped in a non-conductive dielectric layer. This core is then surrounded by a metal braid and protected by an insulating sheath. The name “coaxial” derives from the fact that all layers share the same geometric axis.
Manufactured to transmit high-frequency signals, coaxial cables excel in preventing electromagnetic interference (EMI) and radio frequency interference (RFI) from external sources. By keeping data secure within center conductors and employing additional shielding layers, coaxial cables effectively reduce EMI.
The first-ever coaxial cable system for information transmission was developed by AT&T Corporation in the United States back in 1940. Since then, coaxial cables have become widely used in cable television technology, camera signal transmission, and numerous other applications.
The Structure of a Coaxial Cable
Coaxial cables are designed to transport data while shielding it from interference and potential harm. They consist of four key components:
Structure of a Coaxial Cable
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Center Conductor: At the heart of the cable lies the center conductor, typically composed of solid copper wire, copper-plated metal, or a combination of small strands twisted together to form a single coaxial cable.
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Dielectric Insulator: The dielectric insulator separates the outer and inner wires, fixing the core’s position and preventing signal and current loss. Common materials used for insulation include solid plastic, foam plastic, PE, and PTFE.
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Outer Conductor (Conducting shield): The outer conductor comprises numerous metal wires forming either a braided mesh or a metal foil. It is often made of copper-plated or silver-plated steel. The metal braided mesh layer varies in coverage depending on the manufacturer, with up to four mesh layers aimed at minimizing interference signals that could affect internal signal transmission.
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Plastic Jacket: The plastic jacket, typically made of durable PVC, safeguards the conductor layer from external factors such as flame retardancy, oxidation resistance, water resistance, and UV protection.
Moreover, some coaxial cables may feature an additional layer of metallic ribbon, usually composed of aluminum foil or aluminum foil with complete coverage. This extra layer protects against radio frequency interference (RFI). The protective sheath of each cable adheres to standardized specifications based on the cable’s intended application.
Pros and Cons of Coaxial Cable Usage
To make informed decisions regarding coaxial cables, it’s crucial to comprehend their advantages and disadvantages. Let’s take a closer look:
Advantages
Coaxial cables ensure optimal signal integrity as the digital signal remains contained within the cable’s core, shielded by a non-conductive dielectric layer and robust protective layers. This feature enables you to install cables near metal materials without worrying about energy loss, a common issue with older cables. Coaxial cables provide excellent information security by effectively controlling information loss and leakage.
When used alongside power cables, coaxial cables deliver interference-free signals, unaffected by external power sources. Moreover, their extensive mesh coverage ensures secure connections and exceptional audio quality.
Coaxial cables are simple to install, flexible in design, and highly durable. They can withstand extreme weather conditions and environmental factors like temperature fluctuations. The connectors accompanying these cables are user-friendly and cost-effective, reducing expenses for users.
These cables, also known as network cables, are compatible with broadband systems and offer longer transmission ranges compared to twisted pair cables.
Disadvantages
One drawback of coaxial cables is their potential impact on the overall system. If a single cable fails, it can cause a network outage affecting the entire system. Additionally, signal quality decreases the farther away you are from the center, influenced by cable length, wire condition, and potential electromagnetic interference from other electronic devices. Coaxial cable networks consume a significant amount of electricity, resulting in increased energy costs.
Types of Coaxial Cables
The market offers a wide range of coaxial cables, manufactured by numerous suppliers. Coaxial cables can be classified based on different criteria, including:
According to Size
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Thin coaxial cable: With a diameter of approximately 0.25 inches, thin coaxial cables are affordable, flexible, and durable. They are commonly used for LAN connections and are part of the RG58 family. These cables measure around 6mm in diameter, with a maximum segment length of 185m and a transfer rate of 10 Mbps. They utilize BNC connectors and T-pieces (BNC-T).
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Thick coaxial cable: Having a diameter twice the size of thin coaxial cables (around 0.5 inches), thick coaxial cables are more rigid and challenging to work with but offer a transmission distance of up to 500m. They are suitable for backbone and WAN setups, belong to the RG5 family, feature a 13mm diameter, and can achieve a communication speed of up to 35 Mbit/s.
According to Anti-Interference Cover
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Coaxial cable with an anti-interference shield: This type of coaxial cable comes equipped with a metal shield to enhance its interference-reducing capabilities. Theoretically, it can transmit data at a rate of approximately 500 Mbps, although practical usage typically reaches about 155 Mbps. To benefit fully from the anti-interference shield, proper installation is vital.
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Coaxial cable without an anti-interference shield: Designed for locations devoid of electric fields or other interfering elements, these cables are often used in construction sites. They are generally more affordable compared to their shielded counterparts.
According to Impedance
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50Ω Coaxial Cables: These cables are ideal for radio transmission, Ethernet networks utilizing coaxial cables, and high-frequency digital transmission lines.
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75Ω Coaxial Cables: Widely used in household setups involving video/audio transmission and telecommunications functions.
Although other impedance types, such as 52Ω and 93Ω, are available, they are less popular compared to the aforementioned types.
According to RG (Radio Guide)
Coaxial cables are also identified by their RG (Radio Guide) designations. Cable names start with the letters RG, followed by a number (sometimes combined with letters) representing the cable type. This classification system simplifies cable connector selection.
Some common coaxial cables include RG-6, RG-59, RG-179, coaxial cable 3C-2V, coaxial cable 5C-2V, coaxial cable RG-6, RG-11, QR-320, QR-540, QR-715, QR-860, QR-1125 coaxial cable (ANSI/SCTE series, IEC 61196 series of standards), and many more. The most popular options are RG6 and RG59.
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RG6 cable: Recommended for applications requiring basic band (Base band) and shorter signal transmission distances, RG6 coaxial cables are commonly used for transmitting CCTV data, connecting television equipment, and indoor television setups. They can transmit signals over distances ranging from 225m to less than 545m.
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RG59 cable: Specifically designed for CCTV systems in elevators, RG59 coaxial cables are often used for analog cameras or applications that require flexible, frequently bent cables. Typically, RG59 coaxial cables are used for distances of less than 225m.
Compared to the previously mentioned cables, RG-6 coaxial cables feature a larger central signal transmission core and a thinner layer of insulation. RG-6 cables often have two to four layers of protection, while RG-59 cables typically offer only one layer.
RG-59 cables are suitable for low-frequency, short-range signal transmission, while RG-6 cables excel in high-frequency, long-range signal transmission.
Apart from these options, individuals can also create customized coaxial cables to meet specific requirements, such as moisture-resistant cables or cables with dedicated power for analog camera systems.
Applications of Coaxial Cables
Thanks to their remarkable advantages, coaxial cables find extensive use across various fields. Cable television technology relies heavily on coaxial cables, where they play a crucial role. Additionally, they are employed in communication networks requiring multiple simultaneous connections, CCTV systems, commercial broadcasting, broadband internet connections, BTS stations, and more. Coaxial cables prove suitable for both analog and digital transmission technologies.
Video: RG-6 and RG-59 coaxial cables are commonly used for video applications. RG-59 is considered the industry standard, while RG-6 is recommended for digital signals.
CCTV Camera: For CCTV or security cameras, RG-59 coaxial cables are the preferred choice, although RG-6 can be used for longer distances. Each cable type has its pros and cons. While RG-6 offers longer transmission capabilities, it is bulkier and requires more effort to handle compared to RG-59.
Internet: Coaxial cables serve as carriers of internet connection signals, operating at higher frequencies than traditional cables. To meet this requirement, the RG-6 cable, featuring a larger conductor and thicker dielectric insulation, was created. RG-6 cables also possess an improved shielding layer, enabling more efficient transmission of GHz signal levels.
TV: When it comes to television usage, we recommend RG-6 coaxial cables, focusing on obtaining the highest quality possible. Poor-quality coaxial cables can lead to subpar TV reception. Aim for cables within the 75-ohm and RG-6 ranges.
HDTV Apps: High-definition TVs require stronger signals, necessitating larger gauge cables and more space for signal transmission. RG-11 is considered the best coaxial cable for high-definition televisions.
Can You Use Coaxial Cables as Speaker Cables?
If you’re wondering whether coaxial cables can serve as speaker wires, the answer is a resounding yes. Coaxial cables can indeed be used as speaker wires since they function similarly. However, to ensure optimal performance, it’s necessary to replace the standard F-connectors with RCA connectors enabling perfect compatibility. Ordinary in-house speakers can be used, although subwoofers are often recommended.
One issue with using coaxial cables as speaker wires lies in the impedance load they add to the power amplifier. High-power setups may encounter challenges due to increased resistance across the system.
Essential Information about Coaxial Speaker Cables
Coaxial speaker cables typically feature male RCA jacks at both ends. These cables enable lossless audio output and are highly resistant to interference. They prove valuable for powering various devices, including cable/satellite boxes, DVRs, HDTVs, DVD players, subwoofers, game consoles, and more.
These cables, designed to carry RF signals from source devices to destination devices, find extensive usage in professional home audio systems, guaranteeing consistent sound quality. Covering the 20 kHz to 300 GHz radio frequency spectrum, coaxial speaker cables excel at transmitting digital signals, providing greater bandwidth and more reliable connections compared to ordinary audio connections. Furthermore, their robust construction ensures enhanced durability.
Coaxial speaker cables cater to speakers and subwoofers with lengths ranging from 75 cm to 6 meters. Specific coaxial speaker cables are specially crafted for subwoofer use, facilitating secure connections and delivering excellent audio. Microphones, particularly professional-grade ones, often utilize XLR cables with 3-pin XLR connectors due to their extremely low signal-to-noise ratio.
Instructions for Using Coaxial Cable as Speaker Wire
1. Remove the Coax Connectors
Most residential coaxial cables come equipped with connectors on both ends for connecting to output and power sources. To connect your speakers to coaxial cables, you first need to remove the coaxial connectors. Utilize a sharp utility knife to carefully cut off the connectors. Prior to cutting the cable ends, you may need to remove any wire sheath.
2. Measure the Length
Coaxial cables are available in various lengths, necessitating measurement and, if required, cutting to size. The desired length depends on your system and speaker arrangement. To determine the appropriate cable length, pull a long piece of wire from the speaker to the receiver or amplifier, calculating the length needed to connect the speaker to the system. Repeat this process for each connection, taking multiple measurements to ensure accuracy.
3. Remove the Jacket
Carefully adjust the length of the knife to cut into the insulation without damaging the electrical cable. Alternatively, if you have a suitable tool such as a fiber optic cable cutter, ensure it is designed for use with coaxial cables and test its compatibility. Inadequate traction may hinder the removal of the cable coating.
4. Shield Unbraiding
With the insulation layer removed, access the shielding covering the wiring beneath it. Gently remove the copper wire without causing any damage. This copper wire serves as the connection for your speakers. Carefully remove the shield until only a single copper wire remains.
5. Insulator Removal
After removing the shield, remove the fuzzy insulation covering the conductor’s exterior. This insulation shields the copper wire, but it must be taken off to access the core wire inside the insulator. A reliable set of drawstrings is required for this task.
Once both ends have the necessary amount of insulator removed, you’re all set.
CONCLUSION:
The ever-evolving technology market offers a broad selection of coaxial cable suppliers, leaving you with numerous choices. When it comes to purchasing genuine, high-quality coaxial cables at the best prices, many people face doubts and concerns.
Before buying coaxial cables, consider a few essential factors. Determine the type of device you plan to use and the required OHM, connection, and impedance specifications. Additionally, calculate the distance your device will need to travel from its source. Remember that shorter distances from the source yield better signal quality, and thicker, shorter cables minimize signal loss compared to thinner cables.
We have provided detailed information about coaxial cables and coaxial speaker cables to assist you in making informed decisions. We hope this shared knowledge proves valuable in your search for the perfect cables.
Curious to learn more? Check out our article on how we selected the best speaker wire for car audio.
