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Can't tune in HDTV channels

carealtor
04-24-2007, 08:34 PM
I have 2 HDTVs in the house. A 55 inch Sony in the media room and a 26 inch Sylvania in the bathroom. For purposes of this discussion, neither is using the Comcast DVR for tuning, but rather the built in tuners. When I first set up the Sylvania using the autoscan, it picked up all the same digital channels that the Sony did. But now when I reran autoscan on the Sylvania, it only picked up *some* of the digital channels. There are channels that show on the Sony but don't on the Sylvania. At first I thought it was all the HD digital channels that it didn't pick up, bup at least one, a PBS channel. But most of the HD digital channels were not picked up by the Sylvania's autoscan. Even more disappointing, they don't come in when manually entered either. *no signal*. I know the channels exist because they tune in fine on the Sony, but are AWOL on the Sylvania. Anyone have any ideas? The only thing I can thing of is that Comcast has somehow changed the signal on the HD channels and the Sony is smart enough to still decode it, but the Sylvania isn't? I don't know if that even make sense or is possible, but it's all I can think of. TIA :hithere:

HiDefRev
04-25-2007, 12:00 AM
It could be that the Sony has a better tuner than the Sylvania. When I was shopping for my current Plasma, the store had all the HDTVs hooked to cable. When I went through the digital channels, I noticed that the Sonys, Hitachis, and Philips were tuning in channels that some of the others could not, even though they were all hooked to the same cable.

oblioman
04-25-2007, 04:36 AM
How are you receiving the Comcast signal - with cablecard? Just because your tv's have ATSC tuners does not mean you will get HD cable. This looks like your Sony has ATSC/QUAM capabilities and the Sylvania only has an ATSC tuner.

bobbeck
04-25-2007, 08:12 AM
In the bathroom, ata boy !!! :)

carealtor
04-25-2007, 09:24 AM
How are you receiving the Comcast signal - with cablecard? .

No, not using a cablecard. Just straight from the cable.

Just because your tv's have ATSC tuners does not mean you will get HD cable. This looks like your Sony has ATSC/QUAM capabilities and the Sylvania only has an ATSC tuner.

But the thing is, I WAS getting all the same HD channels, and I am still able to get the one PBS HD channel.

carealtor
04-25-2007, 09:27 AM
It could be that the Sony has a better tuner than the Sylvania.

Could this still be the problem in light of the fact that I WAS able to get all the same HD channels before and still able to get the one PBS HD channel?

dels28
04-25-2007, 11:54 AM
Oblioman said exactly what I was thinking. I see many tvs in the 22-32 inch range do not have QAM tuners just atsc/ntsc tuners. That is the only difference that I see in your setup. Does the sylvania have a built in QAM tuner?

carealtor
04-25-2007, 06:10 PM
Had to look up QAM tuner :rolleyes:

Wikipedia: A QAM tuner is present in some new digital televisions and similar devices. It enables direct reception of digital cable channels without the use of a set-top box.

If this is a true definition, then it must have QAM tuner, because it will tune a bunch of digital channels. However, I don't see it mentioned in the specs. As mentioned above, it did at one time tune *all* of the digital channels available just fine. Is it possible that some digital channels are able to be received without a QAM tuner? Or is it an all or nothing situation?

carealtor
07-05-2007, 09:51 PM
Sorry to revive an old thread, but I have some new info on this and thought maybe someone would care. As of yesterday, I found the rest of the HD channels on the Sylvania. :banana: They may have been there all along, but I'm not sure. What is really strange, is that they are on a different channel than on the Sony. And what's really strange is that the Sony's autoscan didn't find them. So, in a nutshell, all 6 of the HD broadcasts can be found at 2 different channels. For instance, NBC-HD is at both 3.1 and 88.1, the Sony autoscan found 3.1 and the Sylvania autoscan found 88.1! I can manually tune 88.1 on the Sony and get the channel, but the autoscan did not find it. Conversly, I can't manually tune 3.1 on the Sylvania, and this is what was causing so much of an issue for me a few months ago. It never occured to me that the HD broadcast might be on any other channel other than 3.1, but it is! This makes for an even greater mystery as far as I'm concerned, but ultimately it doesn't matter because I can tune all the HD broadcasts on both TVs, just not on the same channel.

pappylap
07-06-2007, 12:38 AM
the sony is setting the digital channel to what you would normally tune to watch it,I assume channel 3 right? its like this, my analog channel 11 digital counterpart is 58.1 but when my tv tunes it in it shows as channel 11 which is what the stations number has always been in analog, channel 11 cbs get it? confusing I know..
the sylvania must not display the digital channels analog counterpart...
hope this helps

carealtor
07-06-2007, 02:49 PM
No, that's not it. The Sony shows "3.1", not "3".

Lee Stewart
07-06-2007, 03:16 PM
No, that's not it. The Sony shows "3.1", not "3".


Can you give is models #'s for the Sony and the Sylvania - that way we can look at the specs to see if anything comes to light.

carealtor
07-06-2007, 03:32 PM
Sure!

Sony KDF-55WF655
Sylvania 6626LCT

Lee Stewart
07-06-2007, 03:49 PM
Sure!

Sony KDF-55WF655
Sylvania 6626LCT

Sony KDF-55WF655

NTSC and ATSC (HDTV) tuners

Authorized CableCARD ability means the set will receive digital cable television systems services directly from the cable operator without requiring a bulky, external cable box.

Sylvania 6626LCT
<TV>
● Built-In ATSC/NTSC Tuner
● Automatic Channel Preset
● MTS Stereo, SAP Sound System
● Closed Caption Decoder
● V-Chip Function

I have a question? The Sony has a CableCard slot - you would pay less than $3.00 a month for a CC - gets you ALL programming you sign up for - 10 to 17 channels of HD depending on where you live.

They both say they have NTSC/ATSC tuners. Are there more than one input on the TV's for the attachment of the cable?

Is there a menu on the TV to make a selection as far as ATSC channels?

Tv stations are still sumilcasting in analog, digital and HD. This may be causing some confusion in the tuners.

pappylap
07-06-2007, 08:33 PM
No, that's not it. The Sony shows "3.1", not "3".


the digital counterpart for your analog channel 3 is 88.1 that is the digital channel assigned to the station for channel 3 in your area you may also have 3.2 and 3.3 maybe more....your Sony will lock onto the digital signal for channel 3 at 88.1 but it is sophisticated enough to then display it at the channel you are normally used to watching it at or at 3.1 which designates it as a digital couterpart of 3
the sylvania is not.....

Like i said channel 11 in my area is cbs but it is assigned to channel 58.1 and 58.2 channel 5 nbc is assigned to channel 28.1 and 28.2 my tuner once it locks onto the signal at the digital channels assigned will then show the station as the more familiar channel 11.1for cbs or 5.1 for nbc... it is alittle confusing to say the least..

pappylap
07-06-2007, 10:37 PM
Boy do I feel stupid, when I first saw this thread I went immediatly to the latest post I did'nt realize this was dealing with your cable connection.....I was attempting to explain OTA digital signals...the only thing I can add is that maybe the 3.1 channel is the digital feed from comcast and the 88.1 is the high definition feed for that channel they do come in at different levels of your digital channel lineup..
digital cable cbs in my area is channel 3 but high def for that channel is 3 hundred something..

I apologize for not paying attention...just worked a 48 hour shift...

carealtor
07-07-2007, 11:32 PM
Boy do I feel stupid, when I first saw this thread I went immediatly to the latest post I did'nt realize this was dealing with your cable connection.....I was attempting to explain OTA digital signals...the only thing I can add is that maybe the 3.1 channel is the digital feed from comcast and the 88.1 is the high definition feed for that channel they do come in at different levels of your digital channel lineup..
digital cable cbs in my area is channel 3 but high def for that channel is 3 hundred something..

I apologize for not paying attention...just worked a 48 hour shift...

Too funny! I was just about to write that your previous explanation made sense to me. LOL

As far as 3.1 being the digital simulcast and 88.1 being HD... both 3.1 and 88.1 are HD, so that's not it.

carealtor
07-07-2007, 11:51 PM
I have a question? The Sony has a CableCard slot - you would pay less than $3.00 a month for a CC - gets you ALL programming you sign up for - 10 to 17 channels of HD depending on where you live.

I know, I know. When I first got the upgrade and the DVR I inquired about also getting a CC. The very uninformed person on the other end of the phone told me it was "impossible" to have both a DVR and a CC. :rolleyes: I haven't pursued the issue since. I just use the DVR if I want to watch one of the scrambled HD channels.


They both say they have NTSC/ATSC tuners. Are there more than one input on the TV's for the attachment of the cable?

The Sony has a "VHF/UHF" jack and a "Cable" jack. I'm using the "Cable" jack.
The Sylvania only has an "Ant. In" jack.


Is there a menu on the TV to make a selection as far as ATSC channels?

Not sure what you mean, sorry. But I don't think so.

pappylap
07-09-2007, 05:21 PM
Is there a menu on the TV to make a selection as far as ATSC channels?

it is possible that your set, the sony especially may be tuning in OTA digital signals even if you do not have an external antenna hooked to it so you may be getting extra channels...
if you can do a antenna scan only that will show if you are recieving any OTA signals...