You take the guide for granted, but think about it: it wasn’t too long ago that you actually needed a magazine made out of paper to know what was on. By the 1990s, most pay-tv systems (DIRECTV included) included a scrolling TV Guide Channel that let you know what was on, but with well over 100 channels you could miss the beginning of a show while waiting to see whether or not it was on. Such guides also didn’t give you information about the individual episode… for that you still needed something printed.
By the early 2000s all DIRECTV receivers had some sort of interactive guide. The original MPG, or Master Program Guide, had about 1 day of guide data which was more than enough for people who watched live. It was quite the marvel of its day, because it was fully interactive, allowing you to get more information about a show hours in the future and even (with some models) set an autotune for it meaning the receiver would change channels for you automatically.
A 1-day guide was not going to work for DVRs, though. DIRECTV’s first DVRs used guide data provided by TiVo, but by the mid-2000s DIRECTV had developed the Advanced Program Guide (APG) to give up to two weeks of full guide data. APG data was separate from MPG data and a receiver could be set up to pull just three days of guide data if it wasn’t powerful enough to store the whole two weeks.
APG data was, and still is, provided by Tribune Media Services, one of the big players in the (surprisingly lucrative) business of guide data. Tribune provides an ongoing database of shows for the thousands of channels that DIRECTV provides. They pull this information from all the different channels out there. In most cases it’s all electronic, as stations really want to cooperate to make sure their data is right, but in those few cases where stuff is hand entered, there are likely to be typos and errors. Mistakes in guide data are a lot less likely now than they were in times gone by but they do still happen.
Your DIRECTV DVR actually uses the APG data several different ways. Of course it’s used to provide you that nice interactive guide and the search experience you love on DIRECTV, but there are also three separate processes that happen to make sure that you’re not losing shows. There is a super-short-term process that’s running, always scanning the satellite information for last-minute changes. This process “should” keep you from losing programs if something is delayed, but often times broadcasters don’t supply Tribune with that information fast enough. There’s a second process which looks for programs about a week out, and a third process that seems to only run when the DVR is idle that looks even further out. The goal is to give you as much information as possible about what’s going to be recorded.
DIRECTV’s APG has a lot more information than you can see, including special markers that identify a show as a first-run or repeat and special episode IDs. If a show’s guide data is missing some of this information, the DVR will record it just to be safe, which is why you’ll sometimes get episodes that you’ve already seen. Better safe than sorry, say the folks at DIRECTV, and I tend to agree. The big problem is tracking down this missing info, as DIRECTV tends to point the finger at Tribune, Tribune points it at local broadcasters, and local broadcasters point it at content providers, who usually point somewhere else. It can be a source of long-term frustration if there’s a show you like that has consistently bad data.
The APG isn’t wrong that often, though. In fact it’s right so often that you tend to take it for granted. That’s a sign of a system that works really well… you just don’t think about it.