ota channels ending in -2 and -3?
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What "list" are you referring to ?? I don't have the same receiver as you.... They should show up in the program guide and you'd select them like any other channel. Otherwise, using the remote, hit the channel number, i.e. "5", followed by either a "." or "-" and then "2" or "3" and so on. According to this picture, http://hr20.dbstalk.com/images/remote/Full/04-RC32.jpg, I'll guess the button to the left of the "0" will give you a "-".
With "list" i mean "program guide". there are a few channels ending in -2 and -3 that appear but i can't get them despite my antenna. when i select them, it says "searching for signal".When i go to antennaweb.org, and enter my zip 78739 the channels ending in -2 and -3 DON'T EVEN APPEAR on the list as available digital channels. Why can't i get them? my local pbs channel's website lists 18.1 and 18.2 as digital channels. i can only get 18.1 but not 18.2
First, the antennaweb question. Each digital station has one channel allocated to its transmissions, so if you take an analog station transmitting its programs on, say, channel 8, it will transmit its digital signals on a different channel, say channel 25. But when the digital TV scheme was devised, it included the capability of "remapping", of making a station appear as if it were associated with the analog station. This is mainly for marketing reasons - the station used its channel number as a "brand" and did not want to lose it. A station which had invested in getting itself known as "channel 8" did not want to have to say "digital 25", so its channel 25 digital station is "remapped" by the tuner to look like channel 8.1.
The digital stations also have the ability to divide the channel into subchannels, each using only a part of the "channel 25" bandwidth. So as well as 8.1, you might see 8.2 and 8.3. As far as the FCC station information, and the antennaweb database is concerned, these subchannels are all channel 25. So when you run antennaweb, it just shows 8.1 transmitting on 25. (If it were to show 8.1, 8.2 and 8.3, all the entries would be identical.)
Using my channel 8/channel 25 example, because they are all on channel 25, the reception of 8.1, 8.2 and 8.3 is identical. The tuner is actually seeing only channel 25 and then splits the digital data up into three streams to give 8.1, 8.2 and 8.3. So if you see 8.1, you will always see 8.2 and 8.3 if they exist, unless something is wrong with the data that channel 25 carries to tell the tuner that there are three subchannels. Moving your antenna to try to get 8.2 and 8.3 can't help.
The HR20 tunes OTA by downloading a list of the local OTA channels it expects to receive, including all the subchannels. So using my example, the list would contain 8.1, 8.2 and 8.3. What has almost certainly happened to the subchannels that are in the list but you can't receive is that they are no longer being transmitted. In these early days of digital TV, stations sometimes add or remove subchannels, for all sorts of reasons. There have been many subchannels removed recently, mainly because of an FCC ruling extending the rules on educational and children's content to subchannels. So if the subchannels are in the list but not in the transmission any more, you can delete them from the list by editing the OTA channel list in antenna setup on your HR20.
Similarly, a station may be transmitting a subchannel but the HR20 list does not include it (this is probably the case with your 18.2). Since the HR20 has no way of scanning for missing channels (a significant weakness of the HR20 for some people) you won't be able to receive the missing subchannel until DirecTV updates the database to include it in the guide.
The OTA digital locals have the -1, etc numbers. On your HR20 guide, those channel numbers show up as a darker blue background. The digital simulcast channels 18.1, 18.2, 18.3 all come from the same tower so antennaweb is only simplifying a bit, don't worry about that.
It's normal that you may not have signal on all the subchannels at once. They may not be broadcasting all the time. I see the same in my area. You will probably see your .1 channels on all the time, though.
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