What Is Coaxial Cable Used For?
A coaxial cable connects the antenna to receive a TV signal. The quality of the cable largely depends on the reproduction of TV programs.
Let’s explore the concept of a coaxial cable and examine its detailed structure. What antenna cable suits digital television, and which brands are better?
How a TV Cable Works
To transmit the antenna’s signals, you need a wire and a coaxial cable. The term is Latin for “coaxial” and means that two conductors lie on the same axis.
The coaxial cable for TV has the following parts:
- The external insulating sheath protects the feeder from mechanical damage and short circuits.
- The shield protects the conductor from inductive noise. Without the shield, the feeder acts as an antenna, picking up stray electronic signals and noise. The shield essentially functions like a Faraday cage. It comprises a thin braid of wires, aluminum foil, synthetic film, and other materials.
- The internal insulation prevents the shielding layer from short-circuiting to the center core. If such a short circuit occurs, the shielding itself becomes meaningless.
- The central component transmits the signal. Manufacturers make it using high-quality but expensive copper cables or steel wire covered with a galvanized layer.
Also read: You must connect two TVs to the same antenna.
What Is Important When Choosing
Select a cable for the TV antenna according to the seven characteristics:
- The material of the outer sheath.
Manufacturers produce feeders using PVC and light-stabilized polyethylene, which resist ultraviolet rays. However, no one has invented anything better than polyethylene for outdoor installation. An unsuitable coating will damage and break the cable. - Strength of the outer layer.
It’s time to utilize a section of the feeder to test the outer PE or PVC shell by pulling it tightly on itself. If it moves quickly, avoid using the cable, as bending it can damage the screen. - The length of the route through which the cable duct will run.
The conductor’s resistance causes more signal power loss as it gets longer. For long routes (30 feet or more), a cable with a copper core is better than one with a steel core. - The power of the incoming signal.
The equipment picks up intense pulses from the ground-based transmission of television signals. However, the power of the satellite signal is small. Therefore, choosing cables with a copper core for dishes is better. - Diameter of the central core.
The thicker the conductor, the less loss there is in the signal’s passage. However, too-thick conductors may require special adapters for standard connectors. - Cable thickness.
Generally, a more influential feeder has more shielding layers, a thicker center core, and more reliable insulation. However, this is only a rough guide. A high-quality, thin cord may be better suited for installation than a thick, low-quality cord. - The material of the center core.
Copper delivers outstanding signal transmission, while clad steel bolsters durability and reliability. You can easily check the core material by grabbing a magnet and bringing it close to the cable. If it sticks to a magnet, it’s probably steel, not copper.
Also read: How to boost a TV antenna signal.
Most Used Antenna Cables
The three most common types of coaxial cables are RG-6, RG-59, and RG-11. Each cable serves a different purpose. RG stands for Radio Guide, and the RG number refers to the diameter of the cable.
RG-59
Television networks and video surveillance systems use these coaxial cables. They consist of two layers, one outer and one inner, one of PVC foam and the other of polyethylene. They are essentially a cheaper alternative to RG-6.
Pros:
- Excellent shielding, especially when working with HDTV at frequencies below 50 MHz.
- Low price.
- The small center core diameter (0.02-0.023 in, 0.5-0.58 mm) and outer sheath (about 0.24 in, 6 mm) make installation easier in cable channels.
Minuses:
- Narrower frequency range than RG-6 – only 2 GHz.
- Significant signal attenuation is the price to pay for the thin center core. You can’t use RG-59 for long runs, such as stretching over 500 feet or more.
RG-6
Signal wire with a 1.0 mm (0.04 in) diameter comes in two types: copper core or copper-plated steel core. The screen features tough, triple-ply aluminum foil and tinned copper, wrapped in durable PVC.
Pros:
- Wide operating range, up to 3 GHz, enables satellite TV use.
- Using a steel core is a great idea! It helps keep the feeder nice and straight, so you’ll need fewer fasteners to finish the wiring.
- High shielding factor (80-90 dB).
Minuses:
- Brittleness of the outer jacket.
- Inconsistent quality in braiding. Before purchasing, inspect the tightness of the wire shield’s winding.
RG-11
RG-11 is a coaxial cable commonly used when setting up high-definition televisions (HDTVs). It provides more airspace for signal transmission, making it suitable for transmitting powerful HD signals at high speeds. Using low-loss RG-11 cable means better overall signal quality.
Larger diameter cables, such as RG-11, reduce signal loss over longer distances. They also offer increased durability and weather resistance, making them ideal for outdoor applications.
RG-11 is another cable with an impedance of 75 ohms. It’s way tougher and has less signal loss than RG-6, making it perfect for longer cable runs. It provides lower attenuation than RG-6 or RG-59. Here’s an example of an RG-11 cable on Amazon’s website.
Which Brand to Choose
When making your choice, consider the following:
- When working with long overhangs during installation, it’s essential to consider feeder stretch losses. To help reduce these losses, consider choosing brands that feature a steel core. Copper can tear in such cases.
- When setting up satellite TV networks, it is a good idea to use a feeder with minimal signal loss. This process helps ensure the best picture and sound quality. In this situation, amplifiers are technically challenging to use.
- The foil layer, not the braid, is essential for shielding. Therefore, foil cable is ideal for satellite and ground networks with weak signal strength.
