An RF cable is a coaxial cable designed to carry radio frequency signals, which is how television broadcasts travel from an antenna, cable box, or satellite dish to your TV. RF stands for “radio frequency,” and these cables transmit audio and video signals as electromagnetic waves across a frequency range that spans from a few kilohertz up to several gigahertz. If you’ve ever screwed a thick round cable into the back of a TV, you’ve used an RF cable.
How RF Cables Work
An RF cable carries a modulated analog signal from a source (like a rooftop antenna or a wall outlet from your cable provider) to the tuner inside your TV. That tuner does the heavy lifting: it isolates the frequency for each channel, then strips away the carrier wave to recover the picture and sound buried inside. This is why your TV asks you to “scan for channels” after you plug in an antenna. The scan sweeps through available frequencies and locks onto every station it can find.
The cable itself is built in layers. A solid or stranded copper conductor runs down the center, surrounded by a plastic insulator, then a metallic shield (usually braided copper, aluminum foil, or both), and finally a protective outer jacket. The shield is the key feature. It blocks outside electromagnetic interference from reaching the signal traveling through the center conductor, which keeps your picture clean and your audio free of static.
RG6 vs. RG59: Which Cable You Actually Need
Most RF cables you’ll encounter for home TV use fall into two categories: RG6 and RG59. RG6 is the modern standard, and it’s what you should use for virtually any current setup.
- RG6 has a thicker center conductor and an extra layer of aluminum shielding. It handles higher frequencies with less signal loss, making it suitable for HDTV signals, cable TV, satellite dishes, and even broadband internet. At 1 GHz (a frequency common for cable TV’s upper channels), RG6 loses about 6.1 dB of signal strength over 100 feet.
- RG59 has a thinner conductor and works best for short, low-frequency indoor runs. It loses signal faster than RG6 at higher frequencies and cannot carry broadband internet at all. You’ll mostly find it in older installations.
- RG11 is a thicker, less flexible cable designed for long outdoor runs. Its larger conductor means less signal loss over distance (about 5.6 dB per 100 feet at 1 GHz), but it’s harder to route through walls and around corners.
Signal loss scales with distance. A 200-foot run loses twice as much signal as a 100-foot run. If you’re connecting a distant attic antenna to a basement TV, the cable type and length both matter. For most homes, a standard RG6 cable under 100 feet delivers a clean signal without any extra equipment.
The Connector on the End
In North America, RF cables for TV use an F-type connector, the familiar threaded barrel that screws onto the back of your TV or cable box. The screw-on design keeps the connection tight and maintains signal quality, which matters more than you’d think. A loose connector can cause pixelation, channel dropouts, or total signal loss. In parts of Europe and other regions, you may encounter a push-on connector (sometimes called a Belling-Lee or PAL connector) instead, but the cable itself works the same way.
Your TV’s input will usually be labeled “ANT IN,” “RF IN,” or “Coax In.” One end of the cable connects to your signal source (antenna, cable wall plate, or satellite receiver), and the other screws into this port. Hand-tighten it until snug. Over-tightening with pliers can damage the connector or the TV’s port.
RF Cables vs. HDMI
RF cables carry analog signals, which tops out at roughly 480i resolution, the standard-definition picture most people remember from pre-flat-screen TVs. HDMI cables carry digital audio and video together and support resolutions up to 8K, along with HDR and surround sound formats. These are fundamentally different jobs.
You still need an RF cable any time you’re receiving a broadcast signal directly: over-the-air antenna channels, a cable TV feed from the wall, or a satellite dish connection. The TV’s built-in tuner can only receive those signals through the RF input. But once you’re connecting a streaming device, Blu-ray player, or game console to the TV, HDMI is the right cable because those devices output digital signals that RF cables can’t carry.
Many people use both. The RF cable brings in local broadcast channels from an antenna, while HDMI cables connect a streaming stick and a soundbar. They serve different parts of the same setup.
Connecting an Antenna to Your TV
If you’re setting up an over-the-air antenna, the process is straightforward. Plug one end of an RG6 coaxial cable into the antenna’s output and the other end into the ANT IN port on your TV. Then turn on the TV, open the settings menu, and look for “Channel Setup,” “Auto Tuning,” or a similar option. Select “Antenna,” “Air,” or “Over-the-Air” as the source and start the scan. The TV will cycle through all available frequencies and save every channel it detects. This typically takes two to five minutes.
If you get fewer channels than expected, check the cable connection first. A loose F-type connector is the most common culprit. After that, consider the cable length and whether you’re using RG6 rather than an older RG59 cable. Antenna placement also matters, but the cable is the link in the chain that’s easiest to fix.
When RF Cables Still Matter
Despite being an older technology, RF cables aren’t going away. Over-the-air TV is free and available in most areas, and it requires an RF connection. Cable TV providers still deliver their signal through coaxial cable to your home, even if a set-top box converts it to HDMI before it reaches your TV. Satellite dishes connect to receivers with RF cables as well. And in many homes, the existing coaxial wiring in the walls also carries internet service from a cable provider, making these cables part of the broadband infrastructure too.
For anyone setting up a TV antenna or troubleshooting a fuzzy picture, the RF cable is usually the first thing to check. A good RG6 cable with tight F-type connections handles everything a home TV setup demands.