Society of Broadcast Engineers
CHAPTER 24, Inc., MADISON, WI
relevant to the operation and membership of the Madison,
Wisconsin Chapter of the Society of Broadcast Engineers.
Views expressed herein do not necessarily reflect the
official positions of the Society, its officers, or its
members. SBE Chapter 24, Inc. regrets, but is not liable
for, any omissions or errors.
Digital Television (DTV) Information
Digital television (DTV) enables local broadcasters to send a "computer-like" data stream from their towers to a receiver or TV set in your home or office. In that data stream broadcasters can send many things. They are required to send at least one TV program with sound but they can send much more. For example, the pictures and sound being sent can have very high resolution for amazing picture and sound quality. That's called High Definition Television or HDTV. Broadcasters could instead send several "standard definition" TV programs (SDTV) at once. That's called “multicasting.” These "standard definition" digital TV pictures are somewhat lower in clarity and detail than HDTV programs. Broadcasters could send a combination of an HDTV program and one or more SDTV programs as well. They could also send other information that has nothing to do with the TV picture and sound they are sending. Those other services are often referred to as "data casting". In addition something brand new is being deployed now on some DTV stations. Its called MobileTV which will enable reception of local TV while moving. The mobile TV channels will not initially be available on normal DTV sets, a special mobile receiver or hand held device will be necessary.
HOW DO I RECEIVE DTV?
That depends on how you are watching local TV channels. Most television viewers fit into one these different categories: 1) Cable TV subscriber (your TV is connected to a cable), 2) Satellite TV subscriber (your TV is connected to a Dish), 3) Other Video Service subscriber (Your TV is connected to a utility broadband company like AT&T U-Verse or a provider from the internet), or 4) Off-Air TV viewer (your TV is connected to an indoor or outdoor TV antenna). If you are a Cable, Satellite, or other video provider subscriber, your provider works with local broadcasters to insure those channels are available to you in standard definition (SDTV) or High Definition (HDTV) depending on the level of subscription you purchased.
If you are an Over-The-Air TV viewer (you are not paying any company a fee for TV), you have an antenna connected to a newer DTV capable TV set, you have an antenna connected to an HDTV tuner which is connected to an HDTV display, or you have an older TV set connected to a converter box which converts the DTV signals to analog TV signals for your older TV set. In the later case, you cannot experience the higher resolution of HDTV but will instead see any HDTV programming down converted to SDTV for your older TV set.
Some subscription TV viewers also may have one or more off air TV sets somewhere in their home in places other than the main TV viewing room. This is common if rooms in the home were not wired for a subscription service but occassional TV viewing is desired in those rooms.
IF I BUY A NEW DTV SET DO I THROW MY ANALOG SET AWAY?
That depends. Your old analog TV set will continue to work with your older VCR, DVD, DVR, Camcorder, Video Game, or other devices that output an analog TV signal. Those older units will still function with your old analog TV set. Most new DTV sets also have inputs for those older analog-only appliances so you'll have to decide whether you want to keep the old TV set based on what you buy. To be clear, your old analog TV set will not tune in DTV signals from your antenna. Every other analog device connected to your old analog TV set will continue to work as they did before.
WILL MY OLD VCR WORK ON A NEW DIGITAL TV?
Yes and no. If it has video and audio outputs, it will play any pre-recorded programs into the appropriate input of your new DTV. You should realize that simply connecting these devices to your HDTV will not mean that their video will now be in HD. The picture you will see will be in the same standard definition resolution that the device was originally designed for. Your HDTV will convert their signals to be seen on the HD screen but cannot improve the program's resolution.
Here comes the no part. You cannot tune in a DTV signal directly from your antenna with your old analog VCR. To record local DTV programs you will either have to connect a Digital to Analog TV Converter box to your VCR or purchase a different TV recording device that has a DTV tuner built in. The traditional VCR is being replaced by DVD recorders which record directly to a DVD disk, or DVR units which record and play digital programming using a hard drive. If you purchase one of these devices make sure you ask the retailer if it has a DTV off-air tuner built in. You'll need that to record local DTV stations directly from your antenna.
I JUST BOUGHT A NEW TV SO I MUST BE WATCHING DIGITAL?
Most likely this answer is yes. The FCC mandates a DTV tuner in all TV sets made for sale in America. The mandate applies only to the manufacture of TV sets, not retail sales. Therefore retailers might still be selling analog only sets from stock until they have exhausted their inventory. Any TV set with only an analog tuner must be so labeled on the retail shelf. When you buy a TV set its best to specifically ask the retailer if the set you are interested in has a DTV tuner inside. Please note that this mandate does not apply to monitors or displays that are HD Ready but do not contain a TV tuner. Only devices that have TV tuners fall under this Digital TV tuner mandate.
You might wonder what good is an old analog tuner in a TV set. While full power TV stations can only transmit a digital signal, for a time there may be low power analog TV stations in your area that have not yet converted to digital. These low power TV station did not fall under the same DTV conversion mandate as the full power stations, but eventually will also have to convert to digital only.
I WANT TO KNOW MORE ABOUT DIGITAL AND HDTV?
The government has put together an excellent web site that is full of DTV and HDTV information. To get there Click Here.
Are you wondering what type of TV Antenna will best serve you at your location. The Consumer Electronics Association has a web site designed to help you learn about and select the proper antenna to receieve free over-the-air HDTV. Click Here to go there.
Another antenna site loaded with additional information is TV Fool. Don't be fooled by the name, its loaded with off the air viewer information. Click Here to go there.
Also feel free to call your local TV station and ask for the Chief Engineer. They love to talk about HDTV!
Information about local Madison, WI Digital TV Stations
WISC TV, Channel 3 (CBS)
WMTV DV, Channel 15 (NBC)
WKOW TV, Channel 15 (NBC)
Wisconsin Public Television