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Discussion Starter · #1 ·
Could someone please explain to a "beginner" why the picture quality is so bad? What can be done to improve it? Later this year, I had planned on purchasing a stb in order to receive the hd/digital signals that the locals channels are supposed to be broadcasting. I want to watch these digital signals on my current 36" analog set. The main reason that I want to go through this process is because I cannot presently receive all of the local ota channels. Supposedly, when all of the locals become digital, they will be broadcasting from the same general direction, thus allowing for improved reception. That is my first goal, then I would like to move on to a hdtv. Is any of this an obtainable goal..........or is it a pipe dream.
 

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I am not clear on your question. What signal are you referring to when you say "the picture quality is so bad"? If you don't yet have a STB, you are not receiving OTA digital signals. Please provide more information about your local stations. Are they broadcasting digital at this time? How far away are they? Do you receive their analog signals OK?
 

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Discussion Starter · #3 ·
I receive the analog signals very well except for the local NBC affiliate. They have their transmitter in approximately a 45 degree angle difference from the other major networks transmitter. Supposedly, later this summer/fall they will all be transmitting digital signals from the same direction/area, which if I purchase a stb, will allow me to receive "crystal clear" pictures from all of the networks. I know that it won't be hd on my analog set, but it should allow me to receive a sharp picture. Right?????? My question is when I stop by Ovation, Circuit City, Best Buy, etc. the analog picture on the hd sets seem very blurry. I know that the signal is split numerous times for all of the tv's that are connected, but you can watch the same signal on an analog tv & the picture is a lot clearer, sharper. Why is that? I thought the hd sets were supposed to give a sharper/better picture.
 

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Quote:
Originally posted by bnewt
...but you can watch the same signal on an analog tv & the picture is a lot clearer, sharper. Why is that? I thought the hd sets were supposed to give a sharper/better picture.
Analog NTSC OTA signals provide about 480X440 (full screen width) maximum, although most standard sets can display higher resolutions. H/DTV signals can be, among other parameters, 480X704 (enhanced) or 720pX1280 and 1080iX1920 (HDTV). If you can find a H/DTV STB that provides 480X704 in interlaced format, say with an S-video output, your analog set could probably display the higher resolution. Such digital images (originally) should also look better because, unlike NTSC, their B&W and color components haven't been 'combed' together and scrambled. A HDTV adds the benefits of component signal (YPbPr) processing with significantly more color resolution, plus higher B&W resolution capability, plus the ability to display deinterlaced (progressive images), which appear 'smoother' and without interlace artifacts if your deinterlacer does a good job. Although store displays of H/DTV are improving, many do a poor job of showing its benefits.-- John
 

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I suppose it also has to do with the fact that most all HDTV's have a built in line doubler that supposedly makes analog channels look better but yet if that analog signal isnt pristine the doubler not only doubles the picture info but any amount of "garbage" in the signal. Be it OTA, cable or DBS.
 

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Bnewt what you are seeing is standard definition video that is upconverted at the TV station. You can't make something out of nothing. This is the signal seen on the Digital Channel when there is no HD content. Some stations do a better job than others.


The standard definition video tuned in on an analog channel and viewed on an HD display is soft. This is helped by the latest set top boxes. As an example I have an RCA DTC-100 and a Zenith DTV-1080. Tune in an analog station and there noticable difference in the quality of the picture between the two units. Neither of which is near HD quality because the original signal is std def.


One use for a STB before you purchace an HD display is to use the STB to view the digital signal via the s-video connector to your std def TV. This will improve the video over the analog NTSC transmission.


I hope I haven't confused the issue. I am a broadcast engineer dealing with HD in Dallas. This is a great place to get information. Maybe even more than you want at times.

JStigler
 

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Also, bnewt, there is a thread titled Louisville, KY - HDTV Talk (or something like that) in the Local HDTV Info and Reception forum. As you're probably already aware, WKPC-DT (PBS) and WHAS-DT (ABC) are up and running and we're just waiting on the laggards.
 

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Discussion Starter · #8 ·
Quote:
originally posted by JStigler:


One use for a STB before you purchace an HD display is to use the STB to view the digital signal via the s-video connector to your std def TV. This will improve the video over the analog NTSC transmission.
That is my goal at the present time - to enhance my reception of the local NBC affiliate. It is the only ota channel that I can't get decent reception. Then after all of the locals are broadcasting in digital/hd, I want to upgrade my tv.
 

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The trials and tribulations of bnewt's analog NBC reception have been chronicled elsewhere. Basically, his analog channel 3 signal comes to him over unfavorable terrain. Even though he now has a professionally installed, cut-to-channel Yagi, coupled with a ChannelMaster channel 3 Jointenna, his analog reception is still less than pristine.


I do not know the digital assignment for NBC in that market, but if channel 3 analog signal can't be adequately developed over that terrain with that antenna, he may be even worse off when a digital signal, probably at a higher frequency, becomes available.


I am puzzled by the following remark:


"....when I stop by Ovation, Circuit City, Best Buy, etc. the analog picture on the hd sets seem very blurry. I know that the signal is split numerous times for all of the TV's that are connected"


Splitting a broadcast DTV signal has no effect on picture sharpness. If the tuners connected to the so-called HD sets are only receiving analog signals through numerous splits, then these TVs are not displaying the pictures that one would normally develop from broadcast DTV signals that were initially developed from standard resolution analog signals, but if the tuners are receiving decoded 8VSB broadcast signals, then yes, that is probably the picture quality one would see in his own home using comparable equipment.


Bnewt's own viewing needs may best be met when DISH network gets its next spot beam satellite up and running and adds Louisville to its list. He may be living in a nightmarish broadcast reception situation as far as his local NBC DTV reception is concerned.


Bnewt, did you ever buy a ladder? You may wind up being one of those people who needs to try every gimmick in the book, including a rotor and a tilter. Sorry to have to give you the bad news.


Is there any talk of locating their digital transmitter to your Northwest with the other transmitters?
 

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Discussion Starter · #10 ·
Supposedly, all of the digital transmitters will be located in the same vicinity that all of the analog transmitters (except WAVE) are now located. If this is true, I should be able to get a good picture from all of the locals - including WAVE when they go digital. My present analog reception is excellent for WHAS, WLKY, FOX, etc.

Any ideas when DISH will have the locals available???????
 
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