You keep referring to things like "their digital station as one of the subchannels."
Analog broadcasts don't have subchannels. Digital broadcasts can use the full bandwidth as one channel, or up to 6 channels. So ALL subchannels are digital. Do you mean HD when you say digital? Most digital is SD, and that's what subchannels are all about. Often, but not always, the analog signal is broadcast digitally as the "main" channel, either in SD or HD- this can be confusing.
Analog broadcasts don't have subchannels. Digital broadcasts can use the full bandwidth as one channel, or up to 6 channels. So ALL subchannels are digital. Do you mean HD when you say digital? Most digital is SD, and that's what subchannels are all about. Often, but not always, the analog signal is broadcast digitally as the "main" channel, either in SD or HD- this can be confusing.