Posts Tagged ‘HDTV Tech Talk’
Toshiba TVs: A Fade to Black? UPDATED
- Published on Tuesday, 24 August 2010 16:17
- Pete Putman
- 11 Comments
EDITOR’S UPDATE: Toshiba has indeed begun the process of moving its Wayne, NJ consumer products division to Irvine, California; integrating it with the company’s IT division. A press release detailing this move (which I missed, whoops!) came out on May 6, 2010.
Yes, Toshiba is following Samsung’s lead by consolidating the offices and operations of its consumer and professional divisions. But that’s only a sidebar to what is potentially a big (and perhaps insurmountable) problem facing the company, and that’s a slow and steady decline in market share among LCD TV brands.
According to an August 18th press release from industry analyst Riddhi Patel of iSuppli, Toshiba’s LCD TV market share in the United States has shrunken from 7.4% with 570,000 TVs shipped in the 2nd quarter of 2009 to 5.5% with 402,000 shipments in Q2 of 2010.
That’s not an insubstantial number. To put that into starker terms, Toshiba’s LCD TV shipments have dropped by almost 30% in one year, which should be sending up a huge red flag in the company’s executive offices…wherever they wind up next.
What is also alarming is that Toshiba’s market share has now fallen into Pioneer and Hitachi territory from 2007 and 2008. A few years ago, Pioneer had a 7% share among plasma TV shipments that dropped to about 5% within a two-year period (while the company was also hemorrhaging red ink). By late 2008, they had decided to throw in the towel and exited the plasma TV business in the spring of 2009.
Remember Hitachi? They once led the market in rear projection TVs and made some top-notch CRT sets, too. Hitachi was also a leader in plasma technology, building an enormous plasma fab on the island of Kyushu with partner Fujitsu in 1999.
Today, that plant is largely superfluous, as the company has withdrawn from selling plasma TVs. And you won’t find any Hitachi LCD TVs at Best Buy, or HH Gregg, or Wal-Mart, or Sears (they do have some nice Hitachi electric drills, though!).
Looking through the Amazon.com Web site, I found a handful of Hitachi sets that are either the last left in stock, or used models. (And the company was conspicuous by its absence at CES 2010.)
The iSuppli report lists the current top five LCD TV brands as Samsung, Vizio, Sony, LG, and (surprise!) Sanyo, leaving Toshiba in the #6 slot. That’s quite a fall, as they were ranked #4 in Q2 of 2009. Panasonic showed up at #8 with a 3.1% market share, but their core business in plasma TVs.
Another shocker: Sharp, once the leader in LCD TV sales, brought up the rear with a 2.4% share, a decline from 4.7% in Q2 of 2009 and a drop in Y-Y shipments of 49%. Yikes! (Is Sharp on the LCD TV endangered species list, too? That’s another story for another time…)
Given all of the LCD fab capacity in Asia and indications of LCD TV oversupply in the channel, the logical result is another round of price wars. That’s a game that Toshiba can’t compete in, because they don’t manufacture LCD panels, and would have to do some serious shopping in Taiwan and China to keep manufacturing costs down.
However, three of the five brands ahead of them do make LCD panels (Yep, Sanyo does make LCD panels, although they also buy glass on the open market), the exceptions being Vizio and Sony. But Sony is still sitting pretty because they are major investors in both the Korean S-LCD Gen 7 joint venture fab with Samsung and Sharp’s new Gen 10 LCD fab in Kameyama, Japan. (Sony owns about 34% of the Kameyama factory and a corresponding amount of the LCD panel output.)
Toshiba was one of the first companies to introduce LED backlights in their TVs. In fact, they were one of the first companies to use the term ‘LED TV,’ thereby creating instant consumer confusion about perceived differences between LCD and LED TVs.
The past decade hasn’t been kind to Toshiba. Their prized HD-DVD technology was vanquished by Sony’s Blu-ray format (supposedly with the help of a $400 million dollar payoff to Warner Home Media), and the crown jewel – the DVD format – is showing its age and in decline.
Toshiba was one of the few companies to show working 3D TV sets with active shutter technology at CES 2010. And their Cell TV architecture (co-developed with Sony) is a powerful platform on which to build next-gen TV designs that can stream multiple channels of HDTV programs and incorporate hand gesture recognition for operation and control.
But all of that may be for naught, if this negative market share trend continues. It doesn’t help that Toshiba is perceived as a ‘mid range’ TV brand now, according to what an industry colleague heard when he recently visited several Best Buy stores in southern California and could find only two models of Toshiba LCD TVs for sale.
The marketplace is indeed a harsh mistress…
HDTV Tech Talk: I’ve Got The Low-Band DTV Blues (June 2009)
- Published on Thursday, 08 April 2010 15:55
- Pete Putman
- 2 Comments
One of the more interesting stories that has developed following D-Day (June 12) is the trouble that viewers are having in several large markets with low-band TV channels – specifically, channel 6, which is now digital in Albany, NY; Philadelphia, PA, New Haven, CT, and five other TV markets.
There have also been reports of difficulty with stations on channel 7, most notably WLS in Chicago and WABC in New York City. The situation there is quite different, but we’ll take a quick look at it at the end of this article.
THE OP-ED SECTION
First off, let it be said that the FCC’s decision to retain channels 2 through 6 in the DTV channel core was ill advised. These are some of the oldest TV channels in existence and used to be the prime spots for a TV station, since they were the lowest channel numbers on tuners.
But the frequencies in which these channels are located – specifically, from 55 MHz to about 88 MHz, give or take several kilohertz – have long been plagued with impulse noise, such as you’d get from noisy fluorescent lamp ballast, brush motors, or any electronic equipment that creates inductive voltage spikes.
To make matters worse, seasonal signal propagation enhancement, caused by sporadic ionization of the ionosphere’s E-layer, can cause signals on these frequencies to hop across the country and create co-channel interference many thousands of miles away. Ham radio operators like myself refer to this summertime phenomenon as “E-skip,” for short.
Here’s another reason why channels 2 through 6 should have been retired: They require very large antennas for efficient reception. A full-wave loop antenna for channel 2 (56 MHz) would measure 5.4 meters in length, or about 17.5 feet! (Contrast that with a full-wave loop for UHF channel 42, which would be about 18 inches around.)
This makes it problematic to design an indoor antenna with any kind of gain, short of adding an internal amplifier. Unless that amplifier’s design is bullet-proof (and for normal Radio Shack prices, it usually isn’t), the antenna system will be overwhelmed with noise and interference from other nearby RF signals, such as FM radio stations.
THE CHANNEL SIX CONUNDRUM
But that’s water under the bridge now, and 40 stations have decided to stay put on this not-so-valuable real estate. As a result, I’m getting quite a few emails about some bizarre low-band VHF reception issues.
My favorite so far is from a television station monitoring service, whose rooftop channel 5 antenna in West Virginia is being routinely wiped out every day by fluorescent lights in the Ace Hardware below, during normal store hours. (Not impossible to fix, but it will take some detective work.)
Getting back to my home market of Philadelphia, there are plenty of problems with reception of WPVI’s digital signal on channel 6. And it became evident pretty quickly that WPVI was having these problems just 24 hours after shutting down their analog signal on channel 6.
Subsequently, WPVI and CBS affiliate WRGB in Schenectady, NY (also on channel 6, and also experiencing reception issues) applied to the FCC for an emergency authorization to go to higher power.
According to a news story in the June 22 issue of Broadcasting and Cable magazine, “…The FCC granted the station (WPVI) a special temporary authority (STA) to boost its transmission power on Ch. 6 from the relatively low 7.5 kilowatts (kW) to 30.6 kW, the maximum power for the northeastern “Zone 1” region of the U.S.”
WPVI’s original digital signal on June 12 at 1 PM, as seen in Figure 1, wasn’t too shabby to begin with, and I could receive it quite easily on both my rooftop and attic antenna systems. It also came in nicely near the southwest wall of my house, on both floors, while using Eviant’s T7 Card portable digital TV set.
But there are always devils in the details, and you can see them quite clearly immediately to the right of WPVI’s flat-topped 8VSB carrier. Those numerous rounded peaks are FM broadcast stations, the closest of which is on 88.5 MHz (WXPN). Almost immediately adjacent is WRTI’s FM operation on 90.1, followed by WHYY on 90.9, etc.
So, what’s the problem? Those FM stations are co-located at the Roxborough TV tower farm, NW of Center City. And they present very strong signals that can slip through the filters in NITA converter boxes, resulting in interference to the channel 6 signal. What’s more, FM and TV signals mixing in converter box receivers will produce sum and difference frequencies that wind up right in a portion of the channel 6 spectrum.
So what’s likely happening is that closer-in TV viewers, who probably don’t have really long rabbit ears (a full-wave loop @ 85 MHz measures 3.53 meters, or 11.6 feet) are trying to pull in a signal that’s competing with strong, adjacent-channel signals from FM broadcasters. Toss in the usual elevated noise floor from arc lamps, power transformers, air conditioning compressors, and refrigerator motors, and you have a sticky wicket indeed!
WPVI’s Special Temporary Authorization (STA) from the FCC definitely resulted in a stronger signal, as seen in Figure 2. And Figure 3, which shows a wider view of all low-band and high-band VHF channels, plus the FM band, reveals that WPVI’s broadcast is now the strongest TV signal coming out of Philadelphia. (Notice the comparatively weaker signal from WHYY-12, the 8VSB carrier to the far right.) But is WPVI even strong enough now?
In both of my spectrum analyzer screen grabs, you may notice that the FM radio station carriers get progressively weaker as the frequency increases. That’s because I’m using an FM trap to try and attenuate them. But that filter simply isn’t sharp enough to subdue WXPN, WRTY, and WHYY without also affecting the strength of WPVI’s signal.
Only precision signal filters with multiple poles and what we call “Hi-Q” sharp filter skirts can solve this problem. Except that filters like that are VERY expensive to manufacture, and not something you’d put into a $59 converter box or a $500 TV set.
The adjacent channel overload problem is compounded by the use of circular signal polarization from FM stations. This is done among other reasons so that their broadcast signals remain moderately stable in as your drive around in your car. But that’s no help to the home TV viewer, who may try to no avail to weaken the FM signals by positioning their TV antenna horizontally or vertically.
In case you think this is just a “big city” problem, look at Figure 4, which shows the FM carrier immediately upstream from WRGB-6 in Schenectady. Same problem – multiple strong FM stations that can play havoc with converter boxes and integrated TV sets are located immediately adjacent to WRGB’s 8VSB carrier. And similar complaints about lost reception are coming into the chief engineer’s office up there.
OK, SO WHAT DO WE DO NOW?
Unfortunately, there isn’t any “one size fits all” fix to this problem. But there are some things that may work.
Inline signal attenuators: First of all, ATSC signals will come through at very low carrier-to-noise ratios, where analog NTSC signals won’t. It stands to reason that viewers close to the TV antenna farms have more than enough signal to begin with, so the counter-intuitive approach is to add attenuators inline with the antenna leads.
This will result in a weaker signal on channel 6, but will also drag down the levels of FM stations, too. Toss in an inexpensive FM notch filter, and at some point the TV receiver or converter box may be able to make better sense of the differences between the FM and channel 6 8VSB signals.
Of course, for this to work correctly, the attenuator should only be in the VHF antenna line, because it’s also going to clip signals from every TV station upstream from the filter, including high-band VHF and UHF. The VHF antenna should also be horizontally polarized, and not vertically polarized. That means flattening out those rabbit ears, or using a bar antenna or folded dipole on the roof, or in the attic.
Eliminating noise: Another possible problem is broadband noise, as I mentioned earlier. It’s worth checking out DTV reception problems with as many of your home appliances and lights disconnected as possible, to see if some “hash” isn’t getting into your system and creating interference problems.
Such interference would manifest itself on the FM band (Surprise! FM isn’t completely noise-free) as well. Any offending appliances should be replaced or repaired, because they’re likely creating bigger interference problems with other electronic devices in and nearby your home.
Using the wrong antenna: Of course, in more than a few cases, the problem seems to be one of trying to receive VHF channel 6 with a UHF antenna, which of course is akin to trolling for marlin with a Pocket Fisherman.
Many folks don’t realize that WPVI is now relocated a long ways away from its former position on UHF channel 64 (about 771 MHz), and that the small UHF loop antenna that used to work so well to pick up Jim Gardner and Action News is little more than a piece of decorative aluminum when it comes to watching VHF TV channels.
So what’s needed is a pair of longer rabbit ears, or even better yet, a folded dipole antenna that can be mounted on the side of a house, or in the attic – or even on the roof. The size would be ½ the length of a full-wave loop, or about 5 feet 9 inches. (5 feet is close enough for government work.)
This folded loop can be made out of copper tape, aluminum, or stiff wire – anything conductive. Even refrigerator drain hose (also copper) also works. Simply solder the leads of a 300-ohm coaxial balun to the open ends of the loop and run a piece of RG-6 to it, and you’re in business. Here’s a link to a simple folded dipole design, made from TV ribbon wire (twin lead). It’s scalable to any VHF channel.
Of course, you can also try a pair of conventional rabbit ears, but if you’re close in to the TV station (10 miles or less), stay away from amplified designs. They’ll only make the problem worse. On the other hand, WRGB’s chief engineer reported at least one viewer had complained about losing the signal on his rabbit ears antenna…30+ miles away. In that case, the amplifier is a good idea, but a rooftop or attic antenna is a lot more sensible.
MEANWHILE, BACK AT THE RANCH…
The problems that have been reported with reception of VHF channel 7 in New York City and Chicago appear to be arising from either improper antenna selection, or elevated noise floors, a common problem in cities. VHF signals have a tough time penetrating tall buildings, a task that UHF signal seem to handle with more aplomb.
But once again, a UHF antenna is not even close to resonance at 180 MHz (Channel 7). That’s about 1.67 meters, or 5.5 feet for a full-wave loop antenna. The good news is, everyday rabbit ears will usually do the trick here, but you’ll need to experiment with their polarization to see what works best. Fortunately, there aren’t any pesky FM radio station carriers lurking nearby.
What there IS, however, is lots of broadband noise. Figure 5 shows a spectral view of analog channels 7 through 13 in New York City, about 3.5 miles northeast of the Empire State Building, inside a 3rd-floor apartment where I’ve been researching an indoor TV antenna design.
So far, so good! But I wanted a little bit more separation between TV carriers and noise for more reliable DTV reception and to feed multiple TVs. So, I tested an inline preamplifier – with disastrous results. Figure 6 shows that the amplifier boosted channels 7 through 13 by almost 20 dB, but also kicked up the noise floor by the same amount – basically accomplishing nothing.
Lesson learned? I’ll have to come up with most of the gain in the antenna system, and try with different combinations of attenuators and preamps to see how I can add some “active” gain to the system without adding more noise and creating a new set of headaches.
I’ll be conducting more tests on channel 6 reception and also high-band VHF stations during the summer to see what practical solutions myself and others can come up with. Look for more coverage of this issue later in the summer. In the meantime, email any questions and observations you may have about “difficult” DTV stations, so we can share them with other readers.
HDTV Tech Talk Tutorial: 3D Program Formats
- Published on Tuesday, 30 March 2010 16:49
- Pete Putman
- 2 Comments
Here’s a quick tutorial on 3D program and transport formats, all coming to a TV near you.
Have you heard enough about 3D yet?
Probably not. Samsung and Panasonic are long out of the gate, while LG just started its advertising campaign for INFINIA LCD TVs during the NCAA Men’s Basketball Tournament. And there will be more companies following with 3D TVs, Blu-ray players, and a host of accessories.
One question I’ve gotten repeatedly is this: “How do they pack a 3D signal into a conventional cable TV channel?” Another one: “How can DirecTV send out 3D, which is progressive scan? They’re not broadcasting in 1080p!”
Time to wheel out the whiteboard! In a nutshell, here’s how the different 3D transmission formats work.
Earlier this month, the 3D amendments for the HDMI 1.4 standard were released. These standards include a host of broadcast 3D formats, along with the Blu-ray top/bottom packed 1080p frame format. (I’ll touch on that, too.) These mandatory 3D formats must be supported if the HDMI interface is a ‘true’ 3D connection.
That’s not to say that a TV manufacturer won’t support other formats: They can, and they are! Examples of ‘other formats’ include checkerboard, interlaced 3D, line-by-line, and alternate frame. There are even 2D+ depth and other ‘overlay’ formats (think of the FM subcarrier for stereo from the 1950s) that are backwards-compatible with older TVs.
What we’re interested in is what DirecTV, Dish, Comcast, Cox, Discovery, and possibly major TV networks like CBS, NBC, and Fox are doing, and might do. Here’s the short list:
Side by side: This is the format that DirecTV will launch in June. It’s also likely to be used by Comcast, Dish, Cox, and any other multi-channel video system. In the side-by-side system, the left eye and right eye images are anamorphically squeezed to fit into a single 1920x1080i/30 frame. (Figure 1)
That means that each image has half the horizontal resolution, or 960×1080 pixels, when expanded back to its normal shape and presented sequentially. Does this look bad? Not really, considering there’s still over 1 million pixels in each eye. As it turns out, HDMI 1.4a calls for side-by-side exclusively with 1920x1080i video content.
Top + Bottom: This format is more likely to be used by stations transmitting progressive scan signals. Once again, the left and right eye images are anamorphically squeezed and packed into a single frame, except they are aligned one atop the other. This is the standard for 1280x720p/60 and 1920x1080p/24 transmissions. (Figure 2)
In this case, each image has half the vertical resolution of a full HD video frame. For a 1080p program, that’s no big deal – each eye works out to 1920×540 pixels. But 720p comes up short, with an effective resolution of 1280×360 pixels in each eye.
The thinking here is that it’s better to sacrifice vertical resolution in a progressive scan TV system than horizontal resolution. I don’t think it makes much of a difference with 1080p content, but 720p? It may not look as good as it should.
What about the alternative? Using a side-by-side format, this would reduce the resolution of each left and right eye image to 640×720 pixels – not much more than a regular DVD. As a result, adopting 720p as an HD format may leave something to be desired with respect to 3D.
HDMI 1.4a: There are two formats here. One uses a top/bottom dual-frame structure (Figure 3) with a total of 1920×2205 pixels. (45 pixels are a blanking or metadata interval.) This retains full 1080p resolution and the frame rate is 24 (23.98) Hz. The other format is for video games, and oddly enough, it’s at a lower resolution – 1280×720 pixels, with either a 50Hz or 60 (59.94) Hz refresh. (Figure 3)
To summarize, these are the ‘mandatory’ HDMI 1.4a 3D formats. A compatible 3D TV will support all of them. On the other hand, set-top boxes and media players only have to provide one of these signals (for Blu-ray players, it’s the full 1080p top + bottom format exclusively), based on the content being served up.
It’s important to remember that, not matter what delivery (transport) format is used, the 3D TV will present ALL of these as sequential left eye/right eye images, using the same active shutter glasses. Only the physical resolution of the images will vary, along with frame rates.
And now you know the rest of the story…to quote the late, great Paul Harvey.
Samsung, Panasonic Get a Flying Start on 3D
- Published on Wednesday, 10 March 2010 19:16
- Pete Putman
- 9 Comments
This past Tuesday and Wednesday, Samsung and Panasonic showed they’re serious about marketing and selling 3D TVs in the United States with some significant product announcements.
Samsung’s press event, held at the Samsung Experience in the Time Warner Center, showcased numerous demos of 3D plasma and LCD TVs. Content from 3D Blu-ray discs and DirecTV was featured, and DreamWorks Animation head Jeffrey Katzenberg even stopped by to add his two cents to the proceedings, attracting a crowd of paparazzi along the way.
In the LCD line, the LN46C750 (CCFL) will be first out of the gate with 3D support and 240Hz image processing. It is expected to retail for $1q,700 and will be in stores in May. Over in the LED BL LCD line, eight models ranging in size from 40 to 55 inches will handle 3D playback, starting with the $1,999 UN40C7000 and topping out with the 55-inch UN55C9000. Look for shipments to start in March with selected models.
Plasma is still part of the 3D equation at Samsung, and six new PDP TVs are ready to deliver 3D. The 63-inch PN63C8000 sits at the top of the line and will set you back $3,800 (May 2010), while the 50-inch PN-50C7000 can be yours fro just $1,800 (also May 2010).
Got Blu-ray? The BD-C6900 is BD3D compatible and ready to deliver the goods (which is a neat trick, considering that Silicon Image just finalized the HDMI 1.4 delivery formats last week!) for $399. It should show up later this month. Each 3DTV and the Blu-ray player will come with one pair of active shutter glasses. (Samsung is also running a limited-time promotion with two pairs of glasses and a 3D BD copy of Monsters Vs. Aliens with each new TV.)
On Wednesday, Panasonic unveiled its first 3D TV entry, the 50-inch TC-V50PT20 ($2,499). This set will come with one pair of active shutter glasses. Larger models will be rolled out as the year progresses, and there aren’t any plans currently for 42-inch or 46-inch 3D models. (No surprise, considering how inexpensive 50-inch glass has become!)
There’s also a new Blu-ray player, the BDT-300. It will retail for $399 at Best Buy. Want the TV, player, and glasses? You can have the lot for $2,900.
It should be noted that plasma TVs have always had the ability to switch at the high speeds required for 3D (120 Hz)..they just haven’t had the correct interface and HDMI 1.4 support. LCD TVs that process at 240Hz can also juggle a 3D signal nicely. (For that matter, so can 120 Hz sets, but the faster refresh rate does a cleaner job with motion detail.)
It’s possible that many of these sets will be purchased and not used for 3D viewing right away, as consumers want to “future-proof” themselves. Considering how few Blu-ray players are on the market, it’s probably not a bad idea to wait a few months until more product is on the shelves and the market figures out pricing.
As for DBS and cable-delivered 3D, you’ll need an upgraded set-top box with HDMI 1.4 support to view the side-by-side 3D content that most networks are likely to use. DirecTV has already stated its intention to use side-by-side, while ESPN is still in the planning stages.
Keep in mind that both side-by-side and top/bottom 3D delivery formats cut resolution in half. Side by side slices horizontal resolution, while top/bottom pares vertical resolution. For a 1080i image, that means 960×1080 pixels in each eye, while the 720p format gets whacked down to 640×720 pixels per eye…not much better than a DVD.
In contrast, the Blu-ray format delivers two complete 1920×1080 progressive frames (left eye on top, and right eye below) with a blanking interval of about 40 – 45 pixels. So you can expect 3D content from Blu-ray to look much better than network content.
Welcome to the 21st Century
- Published on Tuesday, 12 January 2010 17:26
- Pete Putman
- 1 Comment
OK, so I’m a little late – by ten years.
But better late than never, I always say. And with that, I want to welcome you to HDTVexpert.com 2.0 – a new, updated, and slimmed-down version of the original site, launched way back in November of 2004.
This new look has been in the works for several months. And it’s very much a work in progress. But it will allow me to provide more frequent updates, news stories, and analysis of trends and trade shows – something that was not as easy to do with the previous version of HDTVexpert.com.
You’ll find the same insightful and opinionated coverage as before, in the “Front Line” blog. I’ll also feature selected reviews of significant and groundbreaking products – no more “me, too!” reviews of products you can just as easily find elsewhere on the Internet.
The popular “Catch Pete At” and “HDTV Tech Talk” sections have also been retained. Look for useful tutorials on a wide range of subjects near and dear to the world of HDTV, such as IPTV, broadband television, digital video downloads, storage media, and alternative delivery methods.
The analog TV shutdown is now history. As a result, I won’t be posting as many stories about antennas and DTV reception, although both are still very important topics. I will keep reviews of appropriate DTV reception products posted as long as there is still interest in them.
Because of time and space limitations, the new layout won’t have a Letters section for now. However, feel free to send any questions or comments you may have to me at firstname.lastname@example.org. I’ll compile them from time to time in my Front Line section.
If you are looking for an archived article and review from the past couple of years, I’ll be glad to send it to you as a PDF file – just ask.
I’d also like to take a moment to remember Chris Campbell of CC Graphic Design, who was taken from us suddenly this past December at age 50. Chris developed my first Web site back in 2000 and was responsible for the clean look and easy reads of HDTVexpert.com. We worked together for nearly 20 years and he will be greatly missed.
In closing, I want to say thanks for your continue support. My advertisers appreciate your interest, too! Please continue to patronize their products and Web sites, for it’s their support that keeps HDTVexpert.com going!