Digital broadcast TV explained

(with examples from the Madison, Wisconsin television market)

By Chris Lee
Owner, Leemark Communications
First published online: May 16, 2007
Last updated: August 3, 2020

(This article is geared toward people who don’t have cable television or satellite dish service and receive their TV signals over the air using an antenna. In other words: free TV.)

June 12, 2009 was the last day for analog broadcasting by full-power television stations in the United States. Those stations now broadcast only in digital. According to the federal government Web site, this “will free up parts of the broadcast spectrum for public safety as well as other valuable uses.”

photo of Madison Community Tower located on the city's far-west side
Good-bye analog, hello digital: People who watch TV using an antenna to receive signals from broadcast towers such as this one were affected by the government’s mandate that full-power analog TV broadcasts be ended no later than June 12, 2009. Full-power TV stations in the U.S. now broadcast only digital signals. An ATSC tuner is needed to receive these signals. (photo by Chris Lee)

If you receive your TV signals off the air, your old TVs with NTSC tuners won’t receive any full-power stations in the U.S. anymore, unless you take certain steps. The same is true for old VCRs and even DVD recorders if they have only NTSC tuners in them. In order to receive full-power TV stations over the air, you will need to get:
A) a TV that has an ATSC (digital) tuner,
B) a DTV converter box, or
C) a VCR or DVD recorder with an ATSC tuner in it.

Any device with an ATSC tuner in it should be able to show all of the various kinds of digital broadcast television being used in the U.S. However, a certain device might not be able to show a program at its “native,” higher resolution, but instead may drop it down to a resolution it is capable of displaying.

The mandate for ATSC tuners

As of March 1, 2007, the FCC required every new VCR, DVD recorder, and TV manufactured for sale in the U.S., if it had any tuner at all in it, to have the capability to receive digital broadcast television signals. This means having an ATSC tuner and associated circuitry.

However, some manufacturers get around this mandate with their DVD recorders by having no tuner in it whatsoever. Be careful when buying to look for “ATSC tuner,” if you get your TV off-air. If the product has an “SDTV,” “EDTV” or “HDTV” logo on it, or a “DTV” logo, that should mean it has an ATSC tuner in it.

If you buy a DVD recorder with an ATSC tuner in it, you can use that as your tuner for getting digital television on your old TV. Of course, you might not be able to watch one TV show and record another under this setup, unless you have a TV that also has an ATSC tuner in it.

For people who didn’t want to spend the money on a new TV or DVD recorder, the government ran a coupon program that provided $40 off the price of a DTV converter box. A converter box contains an ATSC tuner to let you watch digital TV on an old analog TV set.

The Good News

While it angered some people that they had to get a new device in order to continue receiving TV over the air, there was some good news in all of this. Digital broadcasting has allowed many people who receive only over-the-air (free) TV to get more stations than before. This is because with digital, stations can compress the video and fit multiple “channels” of programming on their single digital channel assignment.

Even in many smaller TV markets, over-the-air TV viewers can now receive more channels than before because of broadcasters’ practice of placing additional programming content on “subchannels.”

For example, WMTV-TV in Madison, Wisconsin (NBC15) puts its regular programming on one part of its digital space, denoted as 15.1, “The CW” network on 15.2, the “Antenna TV” network on 15.3 and a 24-hour weather channel on 15.4.

Using our old “tube” TV with an NTSC tuner in Madison, we were able to receive six network affiliate stations off the air before the switch to digital, not counting low-power religious stations. But with a digital (ATSC) tuner, we now get many more channels, all for free. See the chart on this page for a full list.

Even better is the fact that all of the channels we receive come in very good, with no ghosting, graininess or fuzz. The digital TV signal is composed of ones and zeros, so if your ATSC tuner can receive the signal well enough to determine the ones and zeros, the picture quality will be good.

It is important to note that although these channels are digital, not all of the content is high definition.

Choosing an antenna

In a given TV market, the channels used for digital broadcasting may be in the UHF band, the VHF band, or both.

photo of Philips MANT950 amplified TV antenna mounted on side of house, under eave of roof (inset photo shows wider view, including copper grounding wire)
Back to the antenna: TV antennas don’t always have the traditional roof-top design, or even “rabbit-ears” design for indoor antennas. This photo shows a Philips MANT950 amplified TV antenna mounted on the side of a house, under the eave of the roof. (The inset photo shows a wider view, including copper wire that grounds the antenna in case of a lightning strike.) The MANT950 is a VHF/UHF antenna for indoor or outdoor use and can be mounted on a wall, in an attic, to a railing, or on a mast with a rotor.

This antenna works great for receiving digital television signals at our house, but we are on a hill and only about 10-12 miles from the TV towers in Madison. We could also use an indoor table-top antenna. If either of these solutions do not work well in your case, a traditional roof-top antenna may be needed. (photo by Chris Lee)

Any VHF/UHF antenna should work with an ATSC tuner — the antenna does not have to say “HDTV compatible” on it. In fact, if all of the digital TV stations in your market are on the UHF band, you would only need a UHF antenna to receive them.

While any VHF/UHF antenna may work in theory for receiving digital TV signals, in practice, getting a usable signal depends on the quality of the antenna and its placement, as well as your particular location in relation to the TV broadcast towers.

A simple non-amplified indoor antenna (sometimes called “rabbit ears”) may work fine if you are relatively close to the TV broadcast towers. Of course, an outdoor antenna mounted on a rooftop will usually give you more consistent reception, and often bring in more stations, especially if you are farther away from the TV towers (such as in a different city) or if there are obstacles in between you and the towers or other reception problems. In between these two choices are an amplified indoor antenna and an amplified outdoor-type antenna placed in an attic.

More information on choosing an antenna can be found at the Consumer Electronics Association’s Web site.

A new era in television

The transition to digital TV broadcasting in the United States has greatly affected people who receive their television off the air. Since June 12, 2009, full-power local TV stations are able to broadcast only digital signals. This means that people need devices with ATSC tuners in order to view the TV channels via antenna. While this change was inconvenient for some people and required some expense, it also brought with it some positives, such as better picture quality and more channels in many markets.

Click here to e-mail a comment on this article.

Top of page

Digital TV for Madison market
station call letters network affiliation displayed channel actual channel
WISC CBS 3.1 11 (VHF)
  MyNetworkTV / TVW 3.2 11 (VHF)
  DABL 3.3 11 (VHF)
  QVC Over the Air 3.4 11 (VHF)
  HSN 3.5 11 (VHF)
  Get TV 8.2 36
  SBN 8.3 36
  Quest 8.4 36
  Shop LC 8.5 36
  Bounce 8.6 36
  QVC-2 8.7 36
WMTV NBC 15.1 19
  The CW 15.2 19
  Antenna TV 15.3 19
  WeatherNation 15.4 19
  Start TV 15.5 19
WHA PBS Wisconsin 21.1 20
  The Wisconsin Channel 21.2 20
  PBS Create 21.3 20
  PBS Kids 21.4 20
W23BW (religious) 3ABN (Three Angels Broadcasting Network) 23.1 23
  3ABN-RM Radio (audio only) 23.4 23
  3ABN-RD Radio (audio only) 23.5 23
  3ABN-RL Radio Latino (audio only) 23.6 23
  Radio 74 (audio only) 23.7 23
WKOW ABC 27.1 26
  Me-TV 27.2 26
  Decades 27.3 26
  Court TV 27.4 26
  True Crime Network 27.5 26
WMSN FOX 47.1 18
  COMET 47.2 18
  CHARGE! 47.3 18
  TBD 47.4 18
WIFS Ion Plus 57.1 21
  Movies! 57.2 21
  Heroes & Icons 57.3 21
  Bounce 57.4 21
  QVC Over the Air 57.5 21
  Laff 57.6 21
  Court TV Mystery 57.7 21
  Grit 57.8 21
  Ion Television HD 57.9 21

Top of page