The Gizmo Report: DirecTV's HR21-700 digital video recorder
In my previous blog posts titled "Disappointed with DirecTV" (part 1, part 2) I described the problems I've had getting my DirecTV equipment upgraded for compatibility with the company's new MPEG-4 satellite broadcasts.
Today, I'll be reviewing the centerpiece of this upgrade: DirecTV's HR21-700 digital video recorder (DVR).
Since there's a great summary of the features of this product in this PDF from dbstalk.com, I won't try to rehash all the details. But I do want to describe my experiences using this gizmo, and compare it directly to my older HR10-250 TiVO DVR.
First, the "-700" in the model number is pretty much irrelevant. As I understand it, these numbers distinguish units made for DirecTV by different contract manufacturers. On the HR10-250, the "-250" part referred to the size of the hard disk. That certainly isn't true on the HR21-700, so don't be misled. According to that dbstalk.com review, the HR21-700 comes with a 320GB hard drive, but I suspect the particular model of hard disk may vary. I haven't opened mine up, and I don't know how to get the software user interface to tell me the size or type of hard disk inside.
On the outside, the HR21 is a handsome product. It has a nice "piano black" finish and appropriately dim blue LEDs on the front panel. I hate it when consumer electronics gizmos use bright LEDs, especially for home-theater applications; DirecTV got this right. The center control has a blue-lit ring around it, and the lighting appears to spin when the DVR is performing certain functions, like resuming play after a pause.
The remote control, on the other hand, is relatively colorful. The face is white and gray; the buttons are mostly white, black, and gray, with a bright-orange SELECT button in the center, an orange dot on the REC button, and a set of red, green, yellow, and blue buttons that serve various special functions in the user interface. It isn't as comfortable to handle or use as the HR10's TiVo "dogbone" remote, though, and I think it has more buttons than it really needs... three to turn things on or off, separate BACK and EXIT buttons, etc.
The user interface on the HR21 is a mix of good and bad. A lot of the features are just awkward-- odd mixes of hierarchical menus and commands associated with all those buttons on the remote. There are some very nice features, such as easy access to a list of the last several channels viewed-- the HR10 could pop back and forth between the current and last channel, but that was never quite good enough for me.
My disappointment with the HR21 comes from the major features it doesn't have. The biggest failing is the inability to assign the two tuners in the unit to different channels and flip back and forth between them. I used this feature all the time on the TiVo HR10, since it was so convenient. I could take advantage of commercial breaks or boring sections of one show to use the other tuner to look for other shows, pausing and resuming one channel or the other as I flicked back and forth.
The HR21 can record two shows, or record one channel while watching another, and it's possible to switch between the tuners in these modes, but it's much more awkward than the TiVo solution and in practical terms it isn't worth bothering with most of the time. Since this is one of the most attractive features of the HR10, and the HR21 has all the hardware needed to implement it, I can only assume that this feature was deliberately omitted by DirecTV. My guess-- and it's only a guess-- is that the feature is patented by TiVo. Of course, it seems to me that many of the features of the HR21 could be covered by TiVo patents, so I've often wondered if DirecTV got some kind of patent license from TiVo as part of the two companies' earlier cooperative development efforts. I just have no idea what the real situation is.
Another major missing feature is the lack of tuners for local digital TV broadcasts. The older HR20 had these, but the HR21 dropped them, presumably for cost reasons. DirecTV will soon introduce another gizmo called the AM21 that hooks up to the HR21 via USB and provides those missing digital TV receivers. It looks like this is probably how I'll get this capability back after DirecTV (or its local contract installer) screwed up this part of my upgrade, but since the AM21 isn't shipping yet, I can't get DirecTV to tell me for sure whether they'll be able to send me one.
Other features, such as slow-motion playback, are badly implemented. The slow-motion feature sometimes takes several seconds to engage, making it virtually impossible to play back a specific scene in slow motion. When it works, it's also not nearly slow enough. It's so bad that I've basically given up on this feature entirely, relying instead on the freeze-frame and frame-advance features, which work quite well-- even a little better than on the HR10. Similarly, skipping to the beginning or end of the recording buffer often doesn't work as documented.
One thing I find very strange is the way the HR21 implements multiple video formats. The HR10 was very limited in this respect; it can output in 480i (standard-def interlaced video), 480p, 720p, and 1080i (the major modes of digital TV broadcasts) but it gave no further control over letterboxing or stretching the video to help it display properly on the TV. The HR21 offers all of these extra capabilities, but most of them don't do anything useful. Sometimes the standard modes-- the ones that correspond to the basic modes in the HR10-- clip off parts of the active area of the TV program. This is very noticeable and irritating when captions are clipped off in commercials or news programs.
The other problem with the HR21 is that it's not very reliable. Although all the signal-strength measurements are very high, I get frequent video and audio errors. For a second or two, all or part of the screen will dissolve into green blocks and noise, or the audio will stutter. In some cases, I can be sure these errors are not caused by problems receiving the signal, because I can rewind five or ten seconds and the program plays through normally. Since it's playing the same bits the second time, any problems have to lie in the playback circuitry and software.
The HR21 has also recorded entire programs without an audio track. It doesn't help to stop and restart the playback; there's just no audio there as far as the HR21 can tell.
On the other hand, the HR21 hasn't yet rebooted spontaneously, as the HR10 used to do once every month or two. So that's good.
There are some other things I like about the HR21. For example, I record the local and network evening news programs and watch them when I get home. The HR21 is smart enough to treat these recordings as part of the live recording buffer, so as long as the unit is still tuned to the same channel, I can watch one program followed by the other without having to dip into the list of recorded programs.
That list is very well organized on the HR21, with similar programs being grouped together. The HR21's hierarchical list still has room for improvement, but it's better than the HR10's flat list.
The HR21 also makes it easier to select a program in the guide for recording one or all upcoming episodes. With four speeds, rewinding and fast-forwarding are more useful than on the HR10, and the HR21 matches a traditional TiVo feature: after fast-forwarding through commercials, hitting Play causes the unit to back up a few seconds so no part of the program is missed.
I've taken a lot of detailed notes about the behavior of the HR21, but I think I'll skip all of that for now and just deliver the bottom line: the HR21 has some nice features, but the key features it's missing, and the unreliability of basic functions like recording and playback that I've observed on my brand-new model, make it a less than satisfactory product.
I'll continue to accumulate notes on the HR21 and I'll probably post a follow-up in the next few months, especially as I gain experience with some of the unit's advanced features and I get that AM21 or some other way to restore local digital-TV broadcast capability.
Peter N. Glaskowsky is a computer architect in Silicon Valley and a technology analyst for the Envisioneering Group. He has designed chip- and board-level products in the defense and computer industries, managed design teams, and served as editor in chief of the industry newsletter "Microprocessor Report." He is a member of the CNET Blog Network and is not an employee of CNET. Disclosure. 
Recently, for example, I could not get my local ABC affiliate without tons of pixelation and sound sync issues, and when I called Directv, the CSR tried to get me to unplug the HR20 and move it to another part of the house. Right. Simple solution. Are you kidding me?
No, Directv's foray into MPEG4 has been a joke from a hardware perspective, and across the country many of us have been locked into 2-year lease commitments (though there is an impending class action lawsuit that will be argued soon on that front) trying to deal with this ridiculous situation. Worse thing? None of the cable companies or Dish are much better, and the lack of true competition comes down to a "pick your poison" deal. Maybe when FIOS becomes available, I'll make a move.
As for DBSTalk, it is run by nothing more than a bunch of Directv syncophants and apologists who, even with tons of evidence pointing to the contrary (and evidence you have personally experienced), continue to make excuses for Directv's pathetic HD-DVR rollout.
I mean, no dual buffers when their former HD-DVR (the Tivo box) already had that feature years ago? Constant missed recordings, sound dropouts and pixelation? C'mon, give us a break.
Liberty Media will be paying for the sins of Rupert Murdoch for years to come, since they have apparently decided to keep pushing their lousy HD-DVR hardware on subs. Just check the software download trail via DBStalk. Directv is still pushing out "stability" fixes, nearly two years after releasing the HR20. And it's still not stable!!!!
I'm sure Earl will be posting here soon, to defend Directv and his "cutting edge" crowd. Yeah, cutting edge. The stupid box still can't reliably record tv programs for the an unknown, but not small, number of Directv's subs. Cutting edge, my a**.
It's junk. Fancy junk, that I will give you. But the box is a loser because it still can't do what a DVR is supposed to do: Reliably broadcast and record TV programs.
Oh, for full disclosure. I have been banned from DBSTalk, as the "talk" is only tolerated if you basically agree to keep quiet and not take Directv to task on a serious level. Oh, you can get away with a post or two, but sooner or later, Earl and his charges will be there to defend Directv, apologize for their anti-consumer behavior, and try and act like all is well. And if you push them or try to debate the issue, you typically are booted under some silly "insulting the moderator" rule or some such nonsense. It really is hilarious.
Anyway, good luck with your HR21. But thanks for the objective view of the HR20. If you check CNET's user feedback, my review is the first one listed. I gave it 5 out of 10, but did say some nice things about it too. But that was then, and nothing much has changed. That's not good.
I just about had my fill of Directv.
Bruce