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Digital TV problems start to surface

December 5, 2008

So the broadcast industry took 20 years to come up with the digital TV standard and it sure does not live up to all the hype. I have been using over-the-air digital TV for about two years. As you would expect from anything digital, when it works it is pretty good, but when it screws up it “falls off a cliff” as they point out in this great article. .

I could only pick up about five channels, eight at most. And they were never the same ones. Twist the antenna one way and get ABC and NBC. Turn it another way and get CBS and Fox. I couldn’t get any PBS stations at all, which were the real reason I wanted to get a better signal in the first place.

And this;

A digital signal is affected by practically everything – where your TV set is located in your house, the walls in your house, the number of trees in your yard, how close it is to other electronic devices, birds migrating south in the fall. No kidding. A Washington Post story described how a woman who lived on the 20th floor of an apartment building would lose her signal for a few moments every time a plane landed or took off from Reagan National airport.

And this in a comment:

With my converter box the picture is crystal clear - when I can get it. I tried it for a while and the whole family agreed - snow is better than the picture dropping out completely every few minutes. I tried positioning an antenna all over the outside of my house but with no better luck than the indoor one. We had some success with the front door open and the antenna balanced and pointed in a particular direction but that did not seem like a good long term solution.

I told you folks about this last summer but everybody thought that I was a nut since they have been conned to think anything digital has to be better. That is false, and the promises of digital TV are a little suspect too. In short, if the TV station puts up 5 signals in the bandwidth of one, like our PBS affiliate does here, the picture quality sucks, it is full of JPEG artifacts, those blocky jerky crappy pictures. A commenter in my rant said DTV was MPEG2 but MPEG is just a JPEG key frame followed by frame change information for 64 frames and then another JPEG key frame. When you don’t have a lot of bandwidth you have to use low-quality JPEG settings and the picture looks crappy—this shows up any time there are fast scene pans or water or fire. Next up is interference. The government promised there would be less but that is a lie. Digital signals are far more sensitive to disruption. A few bytes lost means the whole digital processor loses sync and the picture (and sound) just disappears for a second. Pretty annoying. If you have cable or satellite don’t worry, this whole DTV scam was part of the deal to screw the broadcast industry so the phone companies can buy the bandwidth. Now that’s a fait accompli, so Google and Intel want to use TV whitespace to put up wifi up and screw the phone companies. Note that the public’s interest is not even on this list, it is only a question of whether the government helps the broadcast industry, the phone companies or the internet companies. You don’t matter, and sorry, you never have.

I will talk about the whitespace in a later post, ‘til then, I hope you live in a metropolitan area and be sure to buy a giant external antenna and mount it as high as you can. Use a tower if you don’t want lighting to burn your house down. And be sure to buy an antenna rotator while you are at it. I just got mine at the last electronic flea market.

Posted by Paul Rako on December 5, 2008 | Comments (20)

August 5, 2009
In response to: Digital TV problems start to surface
donee commented:

Hi All, The FCC is limiting the power output severly. For example Channel 7 in Chicagoland is down under 5 KW! Yikes, an average DXing VHF/UHF Ham station will put out 5 KW ERP! (13 dBd antenna, 160 watts). This is rediculous! Any kinda precipation goes by and Channel 7 drops out. These broadcast station used to run tens of KW on analog into 10 dB omni antennas, or about 10 times the ERP. The rural people are not well served at all by this, and the suburanites (like me) are getting sub-standard service.


July 24, 2009
In response to: Digital TV problems start to surface
daisyreads commented:

I figured there would be problems with reception because I live in the country with tall trees in every direction and, indeed, there are. I could understand a signal not be strong enough for my location, but what makes it come and go? When my dog wags his tail, I lose the signal. It'll work in one antenna position and then suddenly it won't. And then it will again in a few minutes or hours but then again it cuts out. The trees are not moving, I've checked. I've asked the dog to stop wagging his tail. He doesn't understand. Either do I. I've gathered this is another thing we can blame on the Republicans. And I do.


June 20, 2009
In response to: Digital TV problems start to surface
Anne commented:

Well here we are, after the switchover. I have no more channels on TV. I got the converter box over 6 months ago. It didn't work. I was told I had to buy a new antenna. I bought a new antenna. Still did not work. I got one single channel every now and then, but after a few minutes the screen would freeze and it would change to 'no signal'. I was told I had to do the scan. Did the scan. No channels found. I am too far out, there is no cable here and I'll be damned if I buy a dish just because this digital TV BS forces me to. Two million people without TV right now. Thanks for nothing. Oh sure, we'll be blamed for not doing somethign right.


June 18, 2009
In response to: Digital TV problems start to surface
8ph56 commented:

My father who uses the Tvfor news and a few programs each day has a small portable tv with antena He purchased the new and the most recomended converter and we installed it for him. As uSsul the digtal bandwith is a poor substitute for the analog systems As with radio it is dificult to stay in the bandwidth. iE my favorite RADIO station started drifting in and out several years ago when the station upgraded to a digital signal.wITHANALOGi COULD FINETUNE BUT DIGITAL SKIP OVER. Now I guess my Blind 93 year old father is loosing his TV sound too. THIS IS JUST A mONEY GRAB FOR CABLE SATALITE CO'S tHE CONVERTORS DRIFT AND ANY HOUSEHOLD MOVEMENTS (HIS CAT WALKING BY) CUTS THE DIGITAL SIGNAL hE WONDERS WHY AS THE PIXILS, WHICH HE CANNOT SEE DANCE ACROSS THE SCREEN THE BIG PROBLEM FOR HIM IS NOOOO SOUND i GUESS FREEDOM OF THE (DIGITAL) PRESS IS NOT A RIGHT ANYMORE.


June 13, 2009
In response to: Digital TV problems start to surface
Ralph commented:

This digital TV crap is simply another excuse to extort more money from the public. We didn't need it! Analog worked just fine.


January 2, 2009
In response to: Digital TV problems start to surface
Connor commented:

All this is presupposing there would be something worth watching on the box in the first place. I refuse to buy cable until they offer "a la carte" or pay-per-channel so I'm not supporting Focus on the Family shows and, even if I had cable, the offerings there aren't worth the time spent gaining weight on the couch. Since movement conservatism trashed the financial base of PBS (our tax dollars were doing something worthwhile like educating the masses, so they had to yank that, fer sher), those channels mostly offer fundraising telethons now. So much trouble for such small return...


January 2, 2009
In response to: Digital TV problems start to surface
Rochester commented:

I was generally pleased with how well DTV worked. Until last week, that is. We had high winds here on 12/25 and 12/26. All the DTV channels on both TV's here in Rochester, NY were virtually un-watchable: the audio and video were constantly dropping out, seemingly with the windgusts. (Both sets, one a DTV set with an excellent tuner, the other on a government Zenith converter are on inside antannas.) The signal level meters were swinging wildly, from ~15 to ~85. And, I agree, a snowy picture is way better than one that keeps dropping out.


December 22, 2008
In response to: Digital TV problems start to surface
Joao commented:

I live in Portugal, so we still don''t have digital TV over the air, only by cable or satellite. But, 2 years ago I was in Edinburgh, Scotland, UK, at some friends'' house, and over there the TV broadcast is fully digital. They have more than 20 channels, open broadcast, and they have some that are paid channels, like in cable TV. During the time i was there never experienced lost of transmission in the main channels, sometimes just a little of trouble to tune in the channel. My point in this is that there are ways of making digital broadcast more reliable, it depends on the signal provider, but it''s possible. Don''t blame digital TV, just because it''s digital, blame the signal provider that doesn''t want to invest in signal transmission hardware to make it more reliable, or better video compression algorythms or error recovery during transmission.


December 18, 2008
In response to: Digital TV problems start to surface
BigBears2 commented:

I live in the country and I have, from what I know the largest outdoor antenna Radioshack made, a VU-210 and a booster capable of 30db gain. I have always enjoyed clear TV viewing of all the stations in the area for many years. By turning my antenna I could even watch TV stations in the neighboring state and a few out of Canada. This is not the case with DTV, I purchased a Zenith DTT-901 converter box and it can''''t recieve anything from anywhere. It has been stated in several spots online that they, the stations, are not broadcasting their digital signals at full strength or that the digital antennas aren''''t at the tops of the towers yet. We like many other americans can only hope that one or both of these rumors are true. Otherwise I think many americans that live outside the main broadcast areas will discover, even with the best equipment, that they have wasted thier money whether they purchased a converter box or a new digital TV. I think the poor and rual america would have been better served with a free ( local channel only ) cable subsidized by the goverment instead of the $40 coupons that will only get them a new paper weight. I find it oddly disturbing that nobody is covering the stories of those who won''''t recieve DTV signals under any circumstance. Then again I always did think this was nothing more than a plot to force people with old sets to buy new ones and/or force more of the masses to get cable or satilite TV to increase the the pay-tv profits and their control over us and what we see.


December 17, 2008
In response to: Digital TV problems start to surface
Bob Robertson commented:

I have to ask, why is anyone surprised? It's not like DTV was developed through competition in a free market or anything. No, it was mandated by politicians. The final two sentences of the article are the real issue, everything else is distraction. The problem I've had as an anarchist in pointing out how government is destructive to everything it touches, is that everyone has _something_ they think must be accomplished by force. It's fascinating how those _somethings_ are often so very different, showing that there is little or no consensus as to what government "should" be doing anyway.


December 17, 2008
In response to: Digital TV problems start to surface
arclight commented:

@GREG: The FCC Commissioners are appointed by the President but confirmed by the Senate. The Commissioners who set DTV in motion were appointed and confirmed during the Clinton years. Can't blame George Bush for this one. Work on DTV was moving ahead heavily during the late 1990s (I was working on it as a NASA contractor). @PaulRako: Interestingly enough, I heard on a conference call about the white spaces yesterday that the TV broadcasters are now beginning to think about filling the white spaces with hardware designed to meet the requirements for unlicensed equipment but configured to act as TV translators / repeaters. Their plan seems to be that as long as anyone is going to operate in those spaces, it's going to be them!


December 16, 2008
In response to: Digital TV problems start to surface
Chris commented:

I just got the box (Zenith/LG) a couple weeks ago, and overall I'm really happy with it. I could only get a couple clear channels on analog, but now I get all those channels and more. It's true that sometimes a channel that's usually reliable sometimes cuts out. But overall it's been great. I'm using rabbit ears right next to a window. (Mountain view, CA)


December 16, 2008
In response to: Digital TV problems start to surface
Joe commented:

I should have said "channels" not stations, e.g. 24.1, 24.2, 24.3, etc. Also, we are using the Zenith DTT900 converter box(I think there is a newer model now).


December 16, 2008
In response to: Digital TV problems start to surface
Joe commented:

Near Utica, NY I could only get one OTA analog station. Now with digital OTA, I get 11 stations, including several in Syracuse 50 to 60 miles away, most almost perfectly. I use a radio shack amplified antenna (roof, no rotor) HDTV Indoor/Outdoor Directional Antenna, Model: 15-2187, Catalog #: 15-2187, and a second RS TV amplifier down below. Same problem at my folk's home in central Mass. They now get 18 stations. I used the same RS roof antenna (again no rotor) and a Motorola amplifier purchased on eBay. (RS seems to have fixed a problem with an early production model that caused a lot of failures.) Elevation here is about 500 feet above sea level, and 400 feet at my folk's home, which might explain in part our success with digital OTA.


December 8, 2008
In response to: Digital TV problems start to surface
Lora commented:

yea i don't like how digital signal just drops completely, so you can't even guess from the sound or shaky image what was going on in that part of the show. nbc been the most problematic for me where i switch off the digital that keeps crapping out and go to the analog which is just fine and looks good. i haven't even try the pain of timing my digital reciever and vcr simulataneously so that i can still use my vcr for the simplicity of recording local shows. and the digital converter boxes (even after stupid $40 government coupons) are overpriced!!! stupid simple little things. cheaper than a cable subscription yes, but still annoying to have to pay for it all. especially as this article suggests, none of it was for the public's interest.


December 8, 2008
In response to: Digital TV problems start to surface
GREG commented:

Thank you Pres Bush Administration and FCC (Fcc Chief is pres appointed position), Gee you know the rules don''t you?..... The special interests and campaign contributors --yeah whatever you want... the little people --hardworking taxpayers ...don''t exist! Get screwed.... We need to make a law deporting all Bush''s .... since they think Iraq is a great success maybe they can live there!


December 8, 2008
In response to: Digital TV problems start to surface
Mike_NJ commented:

This is only a problem for the poor (those who can't afford Cable or Satellite) and as we all know the poor don't count.


December 8, 2008
In response to: Digital TV problems start to surface
Mike M commented:

ATSC has significant advantages in the US, mostly due to the underdeveloped translator/repeater system. In Europe, main transmitters are not expected to reach much beyond 25 miles, instead relying on relays/repeaters for outlying areas. COFDM also requires quite a bit more power to cover the same area. If you do a search for 8VSB, you can find some articles on this. ATSC handles impulse noise better than COFDM and much of the early multi-path problems have been resolved in newer chip-sets. However, the attempt to use Low-VHF with ATSC is the main down-side of the standard. The impulse noise characteristics are better, but not that good. We will need UHF channels 52-59 in some areas, but they have already been auctioned off. Hopefully, the few other ATSC countries won't make the same mistake, but Canada's heart doesn't seem to be into digital terrestrial at all.


December 7, 2008
In response to: Digital TV problems start to surface
Bozzmonster commented:

A lot of discussion has been spent talking about OTA antenna, service area plots, placement of equipment, etc. Many, including the FCC forget that the typical OTA signal user is more than likely using a pair of rabbit ears in less than optimal conditions. For them, a snowy or ghosty picture is the norm, something they can live with and the lingo they don't understand... and they never needed to. Or, living in a deed-restricted area (ie. apartment or condo) with no additional monetary resources, analog OTA - no matter how poorly received, is the only alternative they have. Unfortunately, digital television is going to serve a smaller percentage of these viewers. If comparing the equal strengh of signal digital vs analog, and the analog signal was weak, but receivable 100% of the time, there is a great likelihood the digital signal cannot be received, or will only be received part time due to the cliff effect. When I speak the lingo to the typical 'plug and play' user, I have to do a lot of explaining to make them understand. In this transition, nobody has gone to bat to say in clear terms 'you aren't going to receive the same stations you did before without a new antenna, even with a converter box.' In my case, I did spend a little money (about $200) for a modest outdoor antenna with rotor and amplifier that does quite well in my area. It even improved my FM radio reception! If I relied on the standard non-amplified indoor antenna, I would only be able watch a fraction of the channels I could pick up in analog form. Though snowy, they were watchable. I'm another one who quite happily dropped cable after fine-tuning my outer antenna, but I am the only one in the whole neighborhood with a new outdoor antenna. I haven't watched analog television in months. However, keep in mind the old 'analog' technology to receive the signal, a quality antenna, is still needed. The physics do not change. The digital signal is still broadcast on UHF and VHF, so the science of receiving antenna still applies.


December 5, 2008
In response to: Digital TV problems start to surface
NotAsBadAsItSounds commented:

I've been using the New OTA for about 9 months. It takes some getting used to. I invested in a 300 dollar outside antenna because most of the channels are going to UHF. I can get good signals from about 60 miles away. I've also found it depends on the tuner, the two overall best ones you can get with the coupon IMHO are the DTVPal and Digital Stream at Radio Shack. What I did was get my antenna db plots, overlay that onto my channel orientations and strenthgs from antennaweb.cpm and TVfool.com to figure out what antennas will block out co-channel interference the most. Its worked pretty well for me.

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