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Discussion Starter · #1 ·
Do they make a device, not a cable box, that will convert the cable coaxial to hdmi. I am installing a 19 inch LCD in the kitchen, using QAM (do not want cable box in kitchen).


However, when I use the regualr coaxial, the picture on the QAM received channels is not very good.


So I was looking for a device to pluf the coaxial into and then output a hdmi cable to the tv to get HD.
 

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If your LCD has a QAM tuner, you need to perform a digital scan to find the unencrypted DT (HD) channels that may be available from your cableco. Does your set have a QAM tuner? It may just have an analog NTSC/digital ATSC tuner. What model is it?
 

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Quote:
Originally Posted by gerst003 /forum/post/12898570


Do they make a device, not a cable box, that will convert the cable coaxial to hdmi. I am installing a 19 inch LCD in the kitchen, using QAM (do not want cable box in kitchen).


However, when I use the regualr coaxial, the picture on the QAM received channels is not very good.


So I was looking for a device to pluf the coaxial into and then output a hdmi cable to the tv to get HD.

I believe at least some HD Tuners has QAM input and HDMI output (for those early adopters or those who bought an "HD Monitor". But then you will have to re-run an HDMI cable to your kitchen. Maybe it is your TV's fault of having a poor QAM tuner. In that case, the solution is much cheaper.
 

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Discussion Starter · #4 ·
The TV has a QAM tuner and I was able to find the channels, i.e. 84.2.


However, because I am only running a coaxial cable, the quality is not what I would expect from HD - not even close.


Being I can't get a cable box, I just want better picture quality without one. I think the only way would be to use component or hdmi to get full HD on the 84.7 type channels.


So I am looking for a device that inputs coax and outputs hdmi. Basically - do the same thing has a hd cable box, but not do any channel decryption.
 

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I'm pretty sure that HDMI can't carry multiple channels so you'd need something to select a channel and send it over HDMI. Like a cable box.
 

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Quote:
Originally Posted by gerst003 /forum/post/12899873


The TV has a QAM tuner and I was able to find the channels, i.e. 84.2.


However, because I am only running a coaxial cable, the quality is not what I would expect from HD - not even close.


Being I can't get a cable box, I just want better picture quality without one. I think the only way would be to use component or hdmi to get full HD on the 84.7 type channels.


So I am looking for a device that inputs coax and outputs hdmi. Basically - do the same thing has a hd cable box, but not do any channel decryption.

The internal QAM tuner is basically the same as any external QAM tuner that you could purchase. There will not be a major quality difference in using an external QAM tuner over the one integrated into your set. Your internal QAM tuner, if tuned to an HD channel, is fully capable of providing full HD. On a 19 inch screen, it should look fantastic. I suspect, you either have not scanned correctly, or you LCD is not setup properly. What channel is 84.2 or 84.7? Maybe they are just digital and not HD channels. What model LCD do you have?


As for your request in the last paragraph, no such thing. I don't think you have a clear understanding of the issue, which leads me to believe that your problem can be solved with a little discussion and explanation.
 

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The TV has a QAM tuner and I was able to find the channels, i.e. 84.2.

QUOTE]


Just because your QM digital tuner is receiving a digital signal does not mean that it is a HD digital channel. All HD is digital but all digital is not HD.

The networks nomally only transmit HD resolution over the xx-1 digital sub channel and transmit SD resolution programs over their xx-2 or xx-3 sub channels since they don't have the bandwidth available to trasnsmit more then one HD channel.
 

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Quote:
Originally Posted by gerst003 /forum/post/12899873


The TV has a QAM tuner and I was able to find the channels, i.e. 84.2.


However, because I am only running a coaxial cable, the quality is not what I would expect from HD - not even close.


Being I can't get a cable box, I just want better picture quality without one. I think the only way would be to use component or hdmi to get full HD on the 84.7 type channels.


So I am looking for a device that inputs coax and outputs hdmi. Basically - do the same thing has a hd cable box, but not do any channel decryption.

There is no such device that does what you are asking, nor will there ever be. The coax cable is carrying a digital signal for QAM stations. The tuner breaks it down into audio and video and sends it to the appropriate places. HDMI is just another form of carrying audio and video on the same cable. It can carry higher quality, uncompressed digital signals. But it cannot improve the quality of the signal input into it. The output signal, regardless of cable type, can only be as good as the input signal, which in this case is coax cable.


I agree with everyone else here that the stations you are seeing are being broadcast in digital, but not HD. With my QAM tuner I get at least 50 digital stations including some VOD channels, but only 5 of them ever have HD content and even then it is only if the TV show was recorded in HD, which is probably only 1/3 of the programs broadcast.
 

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This is a total noob question (my apologies) but this thread seemed as good as any (short of starting a new one), so here goes:


How is it that HD can be carried through coax from an antenna (OTA), from cable (QAM or pay HD), or from a satellite dish to an HD Receiver, yet I have seen numerous sources (online "basics", news articles, "HD for Dummies"-type things, etc.) that say that HD signal can only be carried by HDMI, DVI, and component cables? In fact, I think I read one place that said coax can only carry 480i?


Obviously HD signals can be carried by standard coax, because all three sources (OTA, cable, satellite) use it. So what is "bad" about coax, that it is not used to go from the STB to the TV input?


I'm assuming that these "info experts" don't list it as a type of cable that can "carry HD" because you never see it used between the STB and the TV?


I'm sure this was explained somewhere previously within this forum, but there's so much info here that it's daunting to find. If it's easier than retyping, just point me to the right thread. Again, my apologies for such a noob question.



Thanks!
 

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The signal coming in via coax cable be it OTA, sat or cable is compressed, it's then uncompressed in the cable box/sat tuner/OTA tuner and is passed to the display in uncompressed format.


Compressed OTA is typically around 14 to 18 MB's per sec depending on how the channel is set up by the station, uncompressed 1080i is about 800 MB's per sec.


In the case of this thread the signal is passed compressed into the set and uncompressed by the internal tuner for display.
 

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Just how long of a distance are you runing your coax and how are you connecting into the cable system?

What exactly does your poor picture quality look like?

How large is the LCD screen?

What type of coax are you using? (RG-6?)


Coax cable can send QAM signals a whole lot farther than HDMI can send a video stream. Coax is the way it's commonly done.

It sounds like you have a problem with one of three things:


The way you split the cable signal at your starting point.

Length of cable

The type of cable you used

The tuner in your LCD TV


It would be easy enough to check the tuner by temporarily moving the TV to a cable outlet that you know is in working order.


If you have a low signal strength because of splitters or a long length of cable, a cable signal amplifier at the source makes sense.


It would be possible to use a HD QAM tuner, a high grade HDMI cable, and a RF remote to do things (almost) like you originally described (up to about 35' max.), but you would be spending maybe $400 on Rube Goldberg fix instead of address the problem.
 

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Quote:
Originally Posted by mjones73 /forum/post/12913893


The signal coming in via coax cable be it OTA, sat or cable is compressed, it's then uncompressed in the cable box/sat tuner/OTA tuner and is passed to the display in uncompressed format.


Compressed OTA is typically around 14 to 18 MB's per sec depending on how the channel is set up by the station, uncompressed 1080i is about 800 MB's per sec.

I thought that OTA HD was supposed to be a little "better" than cable or satellite HD because it was not compressed (I know I read that somewhere)? Or is it just less compressed than cable/satellite, but still compressed?
 

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Quote:
Originally Posted by pjpjpjpj /forum/post/12918404


I thought that OTA HD was supposed to be a little "better" than cable or satellite HD because it was not compressed (I know I read that somewhere)? Or is it just less compressed than cable/satellite, but still compressed?

The latter. Well, *sometimes*; some cable providers will recompress the stream, or do rateshaping on the bitstream, to get it to fit into a QAM channel with a couple (or more) other streams at the same time. Some do not. It depends on the provider, and the location (different locations, even those owned by the same provider, often do things *very* differently). They're all still encoded using MPEG-2 at either 720p (1280x720, 16x9, 60fps progressive) or 1080i (1920x1080, 16x9, 30fps interlaced), the variation is in the encoding process.


Edit: Or 480i, but for HD, it's one of the above; also, satellite providers reencode and tend to cut the resolution of the video, hence the references you'll see peppered around to "HD-lite" (usually like 1280x1080i or something along those lines).
 

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Directv is known to cut the resolution on their older MPEG2 compressed 1080i channels due to lack of bandwidth on the older sats, no proof if they are doing it with their newer MPEG4 channels yet. The reports in general is the PQ is similar or equal to OTA feeds for the HD local channels.
 

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hanging an lcd on wall I have coaxial cable where tv will go and coaxial where

hd box will go, tv and cable box will be about 10 feet away from each other. i dont want to see the hdmi cable. is thier some sort of converter i could buy to make it look clean.
 

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Gefen makes a new product that distributes HDMI over a single coax using a sender and receiver combo. It even works through passive splitters! Best bet is to ask a friend if they know any local custom installers. They could probably custom install an HDMI cable for less than the combo.
 

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OK, here's a reason why I need to convert coaxial cable TV in to HDMI: I have an HD TV that I primarily use as an external monitor for my laptop. One day I did something stupid and went to plug the coaxial cable in to the TV. But I forgot to turn it off. Sparks flew.


After cursing myself for 10 minutes I powered everything down and went to plug in the cable to the TV. Then I plugged the TV in to the power strip. The power strip wasn't even on and it blew the fuse at the breaker box. What did I do? I tried it again. It did the same thing.


So I bought a power strip that grounds cable and also has a "grounded" light indicator. The outlet wasn't grounded either.


Until I can get an electrician to do some work in "this old house," I have thought of getting a cable box that has a coaxial input and an HDMI output. I still use the VGA input from my computer and it works fine.


Thanks for reading my long, clutzy story.


extensive online searching continually brought me to this post.
 

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Quote:
Originally Posted by 3wavestudio /forum/post/15721495


OK, here's a reason why I need to convert coaxial cable TV in to HDMI: I have an HD TV that I primarily use as an external monitor for my laptop. One day I did something stupid and went to plug the coaxial cable in to the TV. But I forgot to turn it off. Sparks flew.


After cursing myself for 10 minutes I powered everything down and went to plug in the cable to the TV. Then I plugged the TV in to the power strip. The power strip wasn't even on and it blew the fuse at the breaker box. What did I do? I tried it again. It did the same thing.


So I bought a power strip that grounds cable and also has a "grounded" light indicator. The outlet wasn't grounded either.


Until I can get an electrician to do some work in "this old house," I have thought of getting a cable box that has a coaxial input and an HDMI output. I still use the VGA input from my computer and it works fine.


Thanks for reading my long, clutzy story.


extensive online searching continually brought me to this post.

You may have an electrical current in your cable. You need to get a qualified electrician to examine your problem before someone is injured or killed. Attaching a coaxial cable to a TV that is on is probably not a great idea but should NOT result in sparks.
 

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Quote:
Originally Posted by pjpjpjpj /forum/post/12918404


I thought that OTA HD was supposed to be a little "better" than cable or satellite HD because it was not compressed (I know I read that somewhere)? Or is it just less compressed than cable/satellite, but still compressed?

Supposedly OTA is less compressed than cable/sat TV.

But compression is not the real problem.

The problem (or cause of PQ loss) is that the video compression is lossy.

You can use compression to reduce the size of data files and programs on your PC, but when you uncompress those ZIP files, you get back the original data and files. That's lossless compression.
 

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Quote:
Originally Posted by HDMI Guy /forum/post/15721782


You may have an electrical current in your cable. You need to get a qualified electrician to examine your problem before someone is injured or killed. Attaching a coaxial cable to a TV that is on is probably not a great idea but should NOT result in sparks.

Yeah, sparks indicate something bad, unless it was just static electricity.

If that's the case, you need to learn to ground yourself and discharge the static buildup before touching electronics.
 
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