Ports to Know: What's In/What's Out On Today's TVs


There once were two ways to get a signal into a TV: an RF connector  for antenna or cable and an A/V for composite video and stereo audio. Then, the VCR age succumbed to HDTV, inputs multiplied, and buying a set became more like shopping for a computer. So let's take a look at the inputs to see which ones are hot and which are not.


Your new DTV set should embrace at least one set of A/V inputs in order to accommodate legacy equipment such as an old games console or video cassette player. Digital cameras with a TV output have typically attached to the TV's composite video (yellow) input. Most consumer camcorders, too, share the show on a TV using the set's conventional A/V inputs. Unfortunately, composite video is not high-def capable. Neither is a multi-pin S-Video connection.

Stereo/Composite Video

An S-Video connection does produce better-looking video than a composite cable. but the perceived improvement was left behind in the Analog Age. That's because no matter how many megapixels you've set your camera resolution for or if you're shooting video in high defintion, what you'll see on your HDTV screen connected through composite or S-Video will be a lower-res version image. Neither connection has the bandwidth to exceed VGA (640 x 480) resolution. While TV manufacturers still include composite video, they're now less likely to retain any S-Video input at all since if you really want a sharper picture, you're more likely to plug into a digital connection.


As for that RF connector, the main reason to use it is to take advantage of the TV's internal tuner. If you plan to receive free over-the-air TV, the RF input is where you still screw in the cable from an antenna. You may also be able to get some cable TV channels this way. However, the vast majority of viewers receive their TV channels exclusively through a cable or satellite subscription, and the tuner is built into a separate component like a DVR. (The outboard tuner used to be called a set-top box or STB, but since TVs have become so thin, the term is no longer applicable.)

The entry point for connecting the picture from a high-definition DVR or a Blu-ray Disc player or even a DVD player is through the TV's set of red, blue, and green component video inputs. The trio has the bandwidth to carry a high-def signal, though the audio signal must arrive through a different connection.

Component Video

Component video, which transmits analog signals, is being eclipsed by all-digital HDMI connections, which also carries the audio. The more HDMI ports your TV has, the merrier, since HDMI is showing up on all types of souce components. However, if you've set up a home theater sound system, the receiver is likely to have multiple HDMI inputs, and by switching your source in the receiver, one HDMI input on your TV should serve your day-to-day needs. An extra HDMI port is good for a temporary connection, like the one you use when you come in the door with some just-shot high-def home video.


If you want to connect the picture on a computer directly to the TV, the most likely way to do so is by attaching a cable to the TV's VGA port, also called a PC input or 15-pin D-Sub. This is an analog signal without sound, but you can get high-def image quality. The VGA input on the TV offers an array of 15 holes divided along three lines. To get sound from the computer to the TV, you'll likely use an audio cable with one-pin for the computer and stereo plugs for the TV. However, computer manufacturers are increasingly including an HDMI output, making a single cable connection possible.


You've probably been hearing a lot about the "Connected TV." This refers to the type of TV that can stream content from a computer on your home network or sites on the Internet. This type of TV almost always has an Ethernet (RJ-45) jack for attaching the same type of cable you use for linking computers to your router or cable modem. Some advanced TVs may embed Wi-Fi reception, but even these will include an Ethernet jack for use when a Wi-Fi signal isn't available.


Finally, newer TVs are including one or more USB ports that look just like the ports on your computer. However, unlike your computer, you can't easily install software to take advantage of new devices you plug in. Depending on the TV model, you may be able to attach a USB storage device or camera and play music, photos, and videos directly—all controlled using the TV's remote. Even if the TV doesn't recognize a particular format, you should at least be able to recharge the battery in the camera or music player.


There are a few other TV inputs with their glory days largely behind them besides S-Video. They include FireWire (also known as i.Link) and a CableCARD slot (which allows access to premium channels when the cable is attached to the RF input without requiring an external cable box to authorize reception.)

In terms of outputs from the TV, the most compelling reason to use one is for sending 5.1 digital audio to your receiver from the built-in tuner while watching over-the-air TV. An optical digital audio output is more frequently used than a coaxial digital audio output (which looks like an orange-colored version of a composite video port), but you should be sure that your receiver has a compatible input. Your TV may also have a set of stereo audio outputs for analog outboard sound. Typically, a headphone jack is only found on TVs with smaller-size screens, but some larger sets may have one. The TV may also have a memory card slot so you can transfer, for example, an SD card from your camera to the TV, and depending on the firmware in the TV, play photo slideshows, music, and standard or high-def video. However, some TV manufacturers have been moving away from card slots and toward USB inputs so you can connect a camera directly, or use an optional card reader, or plug in an external USB storage device such as a flash memory stick.

Optical Digital Audio

There are lots of ports-a-calling on today's TVs. Hopefully, this overview will help you decide what you'll need on your new set for plugging into a world of entertainment components..


My Tvs A/V input was knocked off during a move, is there another way for them to get the cable to work on this tv?  I am getting the DVR box too so was thuinking I could just use the Component Cables?


Hi Karen - 

If your cable box and TV offer component I/O then go for it.  The resolution and color are much better than with composite AV.

Would I be able to use a TV with an S-Video input as a Monitor? - BNC-3G SDI from souurce to BNC-3G SDI w/an S-Video adaptor? I don't really need at high resolution, just need to monitor what's going out? (Preview Screen)

Hi Victor -

I do not think this would work at all, Victor.

Which Hd TVs have an audio output port one can use for wireless headphones?

Hi Joan -

VIZIO offers analog RCA audio outputs on many of their televison models:

VIZIO Television at B&H

Please contact us via e-mail if you have additional questions:  [email protected]

I like to watch  YOU TUBE from my pc to the TV.  I attach the VGA cable to the pc, but there are no holes for the vga screws to screw into.  This can be frustrating ---  because it is not secure it pops out frequently.

I would like to bye another pc soon but need to know which pc's have this feature --- ie,. holes to screw the vga cable to the pc.  

Thanks for any advice -- Kind regards -- Angela.

Hi Angela -

Typically the VGA (mini) ports on laptops have no anchoring screws.  The "screw" configuration usually resides on tower or desktop (workstation.) PC's.  I suggest using longer cables so there is less tension on the cable to prevent it from disconnecting.

Please contact us via e-mail if you have additional questions:  [email protected]