What's what when it comes to TV jacks

3/31/2012
BY SAM GROBART
NEW YORK TIMES NEWS SERVICE

Looking at the back of a modern television is like looking at a map of Eastern Europe in the mid-'90s -- it's always in flux.

New connectors pop up, rendering older jacks obsolete. But since plenty of devices could be adapted to work with the older inputs, those features have to stick around for a while. The new ones can be baffling, if only because many do the same things as the old connectors. Here's a map to navigating which cables go where.

USB: A data connection, often used to connect a wireless "dongle" that can get your TV onto your home's Wi-Fi network. Once that's in place, your TV can become a "smart TV," pulling in Internet content (Netflix, Facebook) that you can access -- most likely through a confusing and poorly designed on-screen interface.

HDMI: The current standard for high-definition video and audio connections. HDMI cables carry high-definition video and surround-sound audio in one cable. The content is transmitted digitally, so there's little to no signal degradation, even over long distances.

Composite: The most basic -- and lowest in fidelity -- video connection. Good for connecting older equipment such as camcorders or game consoles that lack the newer, more capable standards. Composite video is often located next to stereo outputs (do not confuse this with Component plugs).

Ex Link: Used in some Samsung televisions, the ex link connection allows you to adjust the angle of certain wall-mounted TVs by using your existing TV's remote control.

LAN or Ethernet: A connector that looks like a telephone cable, but is a little bigger. Used to connect to wired local area networks (aka "a home network"), the LAN jack is what you would use if you did not have Wi-Fi.

Optical Audio: Also known as Toslink, this standard uses fiber-optic cables to transmit high-quality audio from the display to a soundbar, home theater system or an amplifier. Some audio components have moved to the HDMI standard, but there are still many products old and new that use this cable.

Component: Before HDMI, the only way to send high-definition video from a device to a display. Component cables are divided into three plugs -- red, green and blue -- each carrying a part of the video signal. Component cables are video-only, so you still need an audio connection to hear anything.

PC In: Also known as a VGA connector, this is a way to connect a laptop or other personal computer to a television. This connection is video only, so you would need to set up an additional audio connection to hear whatever was coming out of your computer (unless you were happy playing the audio over the computer's speakers).

Antenna In: Also known as a coaxial cable connection. This threaded connection is used to attach an external antenna (to receive over-the-air broadcast signals) or, sometimes, a cable set-top box. Modern set-top boxes usually have HDMI or component connections for a higher-quality connection between devices, so it is unlikely you would use this port.

Audio Out: Also known as RCA jacks, these ubiquitous ports are either red or white, to represent the left and right channels of a stereo signal. They provide low-fidelity audio connections, in that they do not support surround sound. For a higher-quality audio connection, consider optical audio or HDMI.