Tweaking Your Media Center PC's HDTV Lineup
Published: December 7, 2004
One of the coolest new features in Windows XP Media Center Edition 2005 is its support for over-the-air digital TV (DTV), including high-definition TV (HDTV). If you're just beginning to set up HDTV in Media Center, read Getting Started with HDTV in Windows XP Media Center Edition 2005.
Once you have Media Center configured for DTV, this article describes some additional adjustments you can make to improve your overall experience with your Guide lineup of DTV channels. For example, you can search for additional programming services that otherwise wouldn't appear in your lineup. Also you may be able to locate missing program listings for some of your channels and adjust the antenna to increase the TV signal strength. Finally, you can learn how to correct some issues that may be preventing you from successfully tuning to certain channels.
Optimizing your experience will require a little patience and persistence. However, the reward for this effort will be an expanded lineup of available TV channels, all delivered through your Media Center PC in stunning digital quality.
Find the Missing Channel
You've configured DTV in Media Center and are enjoying the beautiful picture quality and Dolby Digital audio, but there's something nagging at you. A channel you're certain is broadcast locally just isn't showing up in the Guide. The lineup information Media Center displays for digital TV is derived from a Federal Communications Commission (FCC) database. Nonetheless, there may still be discrepancies between this data and the set of stations that are actually broadcasting in your region. If this is the case, you'll need to manually add the missing channel to your lineup.
Adding a missing DTV channel is easy, once you have a few important pieces of information about that channel in hand. Unlike old-fashioned analog television where all you need to know is the channel number, tuning to a DTV channel requires knowing three numbers. In the arcane terminology of DTV, these numbers are known as the major channel, the minor channel, and the physical (frequency) channel. Of these, the major channel and minor channel will likely be the easiest to figure out.
The major channel number is typically the same as the number you're familiar with from the broadcaster's existing analog channel. For example, if you have a local broadcaster whose analog programming airs on channel 37, then the major channel number for their digital programming will also be 37. There are occasionally some exceptions to this, which are covered later in the Find the Missing Signal section.
Next is the minor channel number. Understanding the meaning of minor channel numbers requires a deeper explanation of how digital TV works. This is discussed later in the Find the Bonus Channels section. For now, assume that a minor channel number of 1 is what you want in most cases.
Finally, there's the physical channel number. This number represents the assigned frequency on which the digital signal is transmitted. The physical channel number can be difficult to track down, but with some detective work, you should be able to locate it. Often the broadcaster will include both their analog and digital physical channel numbers in the station ID graphics they occasionally show. For example, if you're watching an analog broadcast and you see the station ID displayed as "WMCE-TV 37/DT 23", then you can tell that the DTV physical channel number is 23. You might also be able to find this information at the broadcaster's Web site or by contacting the TV broadcast station to inquire directly. A few other resources you can check are the National Association of Broadcasters and the Consumer Electronics Association's AntennaWeb.
Add Missing DTV Channels
Once the three numbers—major, minor, and physical—are in hand, you can add the missing channel in Media Center.
1. | In Media Center, select Settings, TV, Guide, Add Missing Channels, and then Add DTV Channel. |
2. | Under Digital TV channel, enter the major and minor channel numbers. Media Center will automatically fill in a default value of 1 for the minor channel. 
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3. | On the next page, enter the physical (frequency) channel number under Assigned frequency. 
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4. | Finally, you can assign a name to the new channel you added. 
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5. | When you're done, select Save on the Add Channels page. The next time you visit the Guide your new channel will appear in the lineup. |
Find the Bonus Channels
Before you find bonus channels, it may help to know more about how minor channel numbers are used by broadcasters. The DTV standard gives broadcasters considerable flexibility in how they use the chunk of broadcast spectrum they've been allocated. A standard TV channel has about enough room to deliver 20 megabits of data per second. The broadcaster can choose to use all of that bandwidth for one high-definition program with incredible image detail. Or, they might subdivide the channel, giving most of the bandwidth to one high-def program (at a slightly reduced picture quality), and use the remaining sliver for one standard-definition program (with much lower picture quality) at the same time. Or, the broadcaster might deliver several simultaneous standard-definition programs, all at lower video quality. This technique of using a single channel to deliver multiple programs is called multicasting.
Broadcasters multicast at certain times of the day, and then may not at other times. For example, a popular movie or sporting event may be broadcast in high-definition for full effect and that channel will not be multicast at that time. However, the broadcaster may decide to multicast four simultaneous infomercials during the late-night hours on that same channel. Some even reserve a very low-bandwidth stream just to carry the image of the local weather radar all day long.
So, if your local broadcaster decides to multicast, you as a viewer need some way of distinguishing between the multiple programs. This is where the minor channel number comes in. Most broadcasters assign their primary feed the minor channel number 1. The other feeds, if any, will have different minor channel numbers.
To find out if a broadcaster has additional minor channels available in your region, you should visit the individual broadcaster's Web site or go to CheckHD.com. If your search comes up empty, you can also try to discover minor channels manually using a trial-and-error method in Media Center. However, be prepared because finding channels using a trial-and-error method could take some time.
To manually discover minor channels in Media Center
1. | Select Settings, TV, Guide, Add Missing Channels, and then Add DTV Channel. |
2. | Add different DTV channels using different minor channels 2, 3, 4, etc. for an existing digital broadcaster. As you add multiple channels with varying minor channel numbers, you'll notice that you aren't prompted for the physical channel number each time. This is because the minor channels all share the same physical channel. |
3. | Then tune to each channel in My TV, and see if anything shows up when you try to view them. Again, some minor channels might not be in use at all times, so you might want to try at different hours of the day, such as daytime and prime time, to see what's available. |
4. | Once you figure out which channels have a working signal, you can go to Add Missing Channels to remove the ones that don't work. |
Find the Missing Listings
When you add missing DTV channels, you may notice that the expected channels have been added in the Guide, but that you aren't seeing any TV program information for those channels. Instead, you see a "No data available" message. The same thing can happen for some of the DTV channels automatically added to the guide when you first set up DTV in Media Center. Without program listings, you can't easily schedule your favorite shows to record on these channels.
Often a broadcaster will simultaneously broadcast the same programming on both an analog channel (in standard definition) and on a digital channel (in high definition or standard definition). Media Center attempts to automatically match up your DTV channels with corresponding standard TV channel listings, by using the name, or "call sign" of the broadcaster. For example, if the DTV call sign is "WMCE-DT", Media Center will try to find "WMCE" in your guide and use the same listings for both channels. If it can't make such a match, then the DTV channel will have no listings. There are several ways you may be able to remedy this situation.
If You Have Satellite TV. If you have satellite TV but the local channels are not part of your satellite subscription, then those channels are usually not included in the Guide lineup. As a result, Media Center will be unable to match listings to any DTV channels that correspond with a local analog channel. To make the local channel Guide information available for your DTV listings:
1. | Select Settings, TV, Guide, and then Set Up Guide Listings. |
2. | Enter your local ZIP code or postal code. |
3. | When asked to choose from the available lineups, choose the one whose name includes your local area, rather than the nationwide lineup you likely chose for satellite. |
4. | At the end of Guide setup, Media Center will proceed through Digital TV setup again. Your DTV lineup will be reloaded, and then another attempt is made to match listings to your DTV channels. |
5. | After completing Set Up Guide Listings, you should turn off the channels you do not receive as part of your satellite package in Edit Channels. To turn off a channel, clear the boxes next to the local channels that you do not receive. This will prevent Media Center from scheduling recordings on channels you don't receive. |
Note: Some satellite providers include duplicates of each local channel, at two different channel numbers. Make sure you clear the check boxes next to both of them.
If You're Missing Listings for Only One or Two DTV Channels. If you're only missing listings for one or two DTV channels, a match may have failed due to small variations in the call signs. In this case, you may be able to match the listings to the DTV channel manually.
1. | Select Settings, TV, Guide, and then Edit Digital TV Listings. |
2. | Select the DTV channel that is missing its listings and then press OK on the remote. |
3. | Browse the available list of channels and select the one that matches. |
Note: You can also use Edit Digital TV Listings to remove listings from a DTV channel, in the unlikely case that the automatically matched non-DTV listings don't actually correspond to the programs aired on that DTV channel.
If You Have Added More Minor Channels. Extra minor channels don't get any guide listings automatically assigned to them. Usually, you won't find listings to match up with these channels in your standard TV lineup. However, if you have digital cable that carries these extra minor channels, you can use Edit Digital TV Listings to match them up. If you have basic cable, but not digital cable, you can try steps similar to those listed above for satellite customers:
1. | Select Set Up Guide Listings. |
2. | Use your local ZIP code or postal code. |
3. | When asked to choose from the available lineups, choose your cable provider's digital lineup. |
4. | Complete guide setup and Digital TV setup. |
5. | Use Edit Channels to clear the check boxes next to the digital cable channels that you don't receive. |
6. | Use Edit Digital TV Listings to match up your DTV channels with their corresponding digital cable channels. |
There may be some DTV channels for which you just can't find any listings in the Guide. For these, unfortunately, you'll have to look elsewhere (such as CheckHD.com) to find out what's on, and schedule recordings manually.
To schedule a manual recording in Media Center:
| • | Select My TV, Recorded TV, Add Recording, and then Channel and Time. |
Find the Missing Signal
If you ever see the "No TV Signal" message for one or two of the DTV channels in your lineup, it may be that:
| • | The antenna is too far from the broadcaster's transmitter. |
| • | You need a different kind of antenna to receive the signal. |
| • | The antenna needs to be pointed in a different direction. |
AntennaWeb is a good resource for antenna selection and aiming. While attempting to adjust your antenna, go back to Settings, TV, and then Set Up Digital TV Signal to view the signal strength information for each of your channels.
Feel free to return to this page as many times as needed while you adjust the antenna for the strongest possible signal. However, if you have adjusted the antenna position several times and still can't get a signal for some channels, try again at a different time of the day, since it's possible that the broadcaster might not be on-the-air 24 hours a day. If you still can't get a signal, remove that channel from the Guide by clearing the check box next to that channel on the signal strength page.
If the signal strength page reports that you're getting a good signal for a DTV channel, but you still see "No TV Signal" when you try to tune that channel, it's possible that the DTV guide data downloaded by Media Center has an error. There have been a few cases where the major channel numbers used in Media Center don't match the actual major channel numbers used by the broadcaster. In some areas, a broadcaster's analog signal might be commonly carried by local cable systems on a different channel number than its over-the-air analog channel. In these cases, the broadcaster may have built up brand-recognition around their cable channel number, rather than their over-the-air number. For example, WMCE-TV could appear over-the-air on channel 37, but it might be carried on cable channel 3, in which case the broadcaster might advertise itself as "WMCE 3" and use 3 as its DTV major channel, instead of 37.
In this situation, you'll need to add the missing DTV channel. In this example, use channel number 3-1, instead of 37-1. Once you've verified that this new channel works correctly, you can use Edit Channels to clear the check box next to the original channel that didn't work and hide it from view.
Windows XP Media Center Edition 2005 gives you a number of ways to expand your viewing choices with over-the-air DTV. Using this article's technical explanations of how things work with HDTV in Media Center, you're prepared to discover new channels that are not automatically included in your lineup. Additionally, you can add Guide listings to channels that would otherwise have none, and fine-tune Media Center's ability to receive all the signals available in your local area. Applying these techniques should make your DTV viewing experience more enjoyable.
 | John Elsbree has been writing software for Microsoft for fifteen years. Prior to joining Microsoft, he graduated from the Massachusetts Institute of Technology with degrees in electrical engineering and computer science. When he's not busy tweaking Media Center code, he can usually be found playing with his three children, volunteering at their school, working out at the gym, or kayaking the waters around Washington state's San Juan islands.
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