THE HDTV INBOX — MAY 2008
A True Bargain
Q. Long time fan of your site. I recently went HD and in the process, dropped cable and use a TivoHD to DVR shows via ATSC. The selection and reception in Phoenix is pretty darned good — at the $0.00 monthly fee, it's pretty awesome!
My question is regarding broadcast TV in general. I'm wondering if there is any info out there or even opinion on your part if broadcasting HD TV may find more channels looking forward. It would seem to me that it makes sense at least in major metropolitan areas. I can't complain if I don't get more channels, but admittedly it would be nice if more companies broadcast over the air.
A. It’s up to individual stations how much HDTV content they choose to broadcast. (In the case of network-owned stations, the parent company sets up the menu.) The good news is, more and more daytime programming and news is going to HD, so while the programs may not change much, they will increasingly be broadcast in HD.
There are a few limitations to adding more HD programming for broadcast stations, one being the limited amount of bits available. In an ASTC DTV channel, the maximum bit rate allowed is 19.39 Mb/s. HD content needs most of those bits to look its best, particularly 1080i sports programming. Adding a second 1080i or 720p channel to the mux is asking an awful lot of forgiveness from consumers with large screen HDTVs, as there are sure to be many visible compression artifacts.
Your Results May Vary?
Q. I am intending to buy a new HD LCD 42''. I was in a big retail shop and was talking to the sales guy, he mentioned that life expectancy of LCD TVs is around 3 years, and probably within the 3 years there will be so many dead pixels on the TV that it won’t be usable. Could you let us know your comments on this?
A. Wow — that’s a strange bit of “expert advice” and one that I’d just ignore. There are a couple of things that can fail inside an LCD HDTV, the first being the backlight. The cold-cathode fluorescent lamps (CCFLs) used in almost all LCD HDTVs will eventually fade out and won’t ignite, just like a conventional fluorescent lamp. How long that will take is subject to argument from lamp and TV manufacturers, but LCD TV manufacturers routinely talk about 50,000 to 60,000 hours before ½ brightness.
I recall a test by Dr. Larry Weber, founder of Plasmaco, where he measured the decrease in light output from an off-the-shelf Sharp LCD TV a few years back. In his tests, he set up the TV in its brightest mode, and saw a significant reduction in light output after just 200 hours. On the other hand, I have had various LCD TVs and computer monitors running in my studio for five to six hours a day for several years and the backlights are holding up quite nicely.
Another thing that can fail is the thin film transistor (TFT) uses to control each LCD pixel, but that’s pretty rare these days. Stuck pixels would either show up as black or as a red, green, or blue pixel. This used to be more common in the early days of LCD TVs, with manufacturers like Sharp saying in their sales literature that a handful of dead pixels were to be expected on any LCD TV.
Of course, back then a 28-inch LCD set cost nearly $15,000. Today, you can buy 32-inch LCD TVs for less than 1/15 of that, and even if the backlights only make it to 20,000 hours, that’s equivalent to watching just about six hours of TV, 365 days a year, for ten years – at which point, you’ll probably want a newer TV anyway.
Short And Sweet
Q. Thank you for saving me from a Wal-Mart purchase of the Magnavox.
A. Glad to be of assistance! By the way, the latest word I have is that Wal-Mart will be selling only the Magnavox TB100MW9 east of the Mississippi, with the RCA DTA800 featured in the rest of the country. Hopefully Wal-Mart will add another few models to their selection as time goes on. A newer Magnavox model, the Magnavox TB-100MG9, has analog (NTSC) pass-through capability and may make it to Wal-Mart shelves soon.
I Want My A-TV
Q. Are there any converters in the coupon program that provide the function of programming channel changes for VCR or TiVo recording? How would you recommend scheduled recording with an ATSC (NTIA) converter box and an analog TV?
A. Unfortunately, scheduling recordings is not an option with NTIA digital TV converter boxes. The ability to schedule a channel change and “power up” for recording was never part of the NTIA specification.
You’ll have to invest in a combo VCR/ATSC receiver product, such as LG’s RC-797T. This product has a built-in ATSC/QAM tuner, a DVD recorder/player, and VHS recorder/player, and downconverts all HD signals to standard-definition resolution for recording, bumping them back up for playback. Otherwise, just hook up the RF output or video out cables to your existing VCR, turn the converter box to the desired channel, and record manually.
Good To Go
Q. I am feeling like I am going into this digital TV blind. I have a 27-inch 1992 Sony Trinitron that works great and now I have to get one of these boxes. We don’t watch much TV, but now I have to do this. Do I need an antenna, since I use one now? I don’t have cable or dish.
A. If your antenna is picking up local TV broadcasts cleanly, you should be able to use it for digital reception as well. Keep in mind that you may have a mix of VHF and UHF channels available locally, so your antenna should cover the full range of channels from 2 through 51.
You can find out which channels will be in use in your market by going to the FCC Website and downloading a copy of the final DTV channel election tables. This spreadsheet is in Excel format. Go to http://www.fcc.gov/dtv/ and under the date August 8, 2007; look for FCC Announces Final Assignment of Digital Television Channels.
The Great Outdoors
Q. I'm an attorney in Johnson City, TN. I want to put a television (40" or less) in the outbuilding where I keep my hot tub. There's a good ventilation system (almost an entire wall is open air), so humidity is not an issue, but the temperature in the winter gets don in the low 20's on occasion. I'd like to be able to use the TV in the cold weather, or at least let it sit out there until I do.
What type of HDTV is most cold tolerant — LCD, plasma, DLP, or a conventional cathode-ray tube? I know they make all-weather TVs now, but they're priced outrageously, and this one wouldn't need to withstand precipitation, just low temperatures. Thank you for any help in deciding.
A. I’d say any of them should survive nicely in that temperature range provided you keep them dry. I’ve personally tested a Sanyo waterproof LCD HDTV down below 10 degrees F for over 12 hours with no harmful effects (see my Super Bowl 2007 HDTV Party article), and that was an extreme situation as it stood outdoors with no protection from wind and other elements. Some condensation formed on the surface of the outer protective glass and it took a while to clear, though.
CRTs and plasma HDTVs won’t be adversely affected by temperatures in the 20s, nor will rear-projection HDTVs. However, the flat-panels would make the most sense as you’ll get a larger screen for less weight and have wider viewing angles than an RPTV provides.
A Bug In The System
Q. I read your review of the Zenith DTT900 and promptly went out and purchased one for use with my old analog set. Well, it lasted about 20 minutes before it was re-boxed and taken back to Circuit City. The sibilance and crunchiness of the treble was just horrible on over half the channels here in Los Angeles. Not only that, the volume drop off and the low level hum were totally unacceptable.
I’m not picking on you for recommending this box, and I have read your more recent reviews of other boxes available, but could you please include reviews of the audio performance of these boxes (especially the coaxial connection as I’ve heard the sound is better with the composite, which I don’t have). Sound goes hand in hand with visuals when it comes to judging a TV show or movie, so please, at least mention it. I will say that my first impression with “digital” technology left me feeling like we haven’t gone very far, in fact, somewhat backwards.
A. Glad you mentioned this problem. I got several emails after my review mentioning the “shrill” and tinny audio on the DTT900, something I never heard on my review unit which was shipped in late December of 2007 and which may have been a pre-production unit.
I spoke to Zenith/LG representatives at NAB 2008 and the culprit is an EQ setting in the audio processor. This has been upgraded recently (as has the processing chip). Apparently the problem occurs with a down mix of a Dolby Digital 5.1 surround audio track to stereo, and is not as common when watching programs with native stereo soundtracks. You may want to contact LG’s customer support line at 1-800-793-8896 and see if there is a warranty fix for this problem, or an exchange for upgraded boxes.
Detective Work
Q. I recently read an article on your site about how Comcast was sending the local HD signals over their basic and extended basic cable subscribers. I live in Marin, CA and am able to get several (20 or so channels) HD signals over the air. I ran the channel finder routine for my TV and picked up the local channels over basic cable in HD with 5.1 channel surround sound (if being broadcast).
The funny thing is I noticed that I have tons of cable channels that I don't think I'm supposed to receive. I get all the digital music channels. I even seem to be receiving two or three signals of someone else's DVRs or on Demand. I can watch when they are playing, fast forwarding, pausing, rewinding. Weird! I had several channels that my TV reported as "Digital signal has been encrypted". Any idea of what may be going on?
A. Yep! Your HDTV has not only NTSC and ATSC tuners, but also a quadrature amplitude modulation (QAM) tuner. QAM is the DTV modulation system used by the cable TV industry, and it’s closely related to the VSB system used by terrestrial (over the air) broadcasters.
When you scanned for channels, your HDTV picked up all of the “clear” channels (those without conditional access) along with their associated audio tracks. The channels you couldn’t pick up have been encoded in Motorola’s DigiCipher format, which cannot be understood by your HDTV.
As for those music and VOD channels, Comcast doesn’t bother to encode those. That means you may stumble across a VOD playback accessed by one of your neighbors from time to time. You’ll probably find a few cable-only networks in the clear as well, like History, MSNBC, and Bravo (all in standard definition, the HD versions are encrypted).
The Basics
Q. I just saw your review of the Digital Stream DTX9900 and was hoping you could help me. I agree it's very user friendly, but I do have one problem: While I'm getting great digital stations on my TV, I'm still getting analog on my DVD player. What's do you think is wrong with my setup?
A. You didn’t specify if your DVD player is just that, or if it’s a combo player with a TV receiver and the ability to record shows to DVDs for later playback. If the latter, then you won’t be able to use the DVD recorder to record digital TV shows unless you connect the Digital Stream receiver to its line inputs (yellow RCA jack and red/white audio jacks) and record programs in real time. (See “I Want My A-TV,” above.
