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Missing HD Channels

03-31-2008, 07:24 AM

I have a new HDTV, and I'm using Time Warner with a converter box.

I'm getting some of the HD channels, but not others. Thus, I'm getting ESPN on channel 950, but not ESPN2 on 951. I'm getting NBCHD on 805, and PBS on 800, but I'm not getting CNN on 839, Food channel, etc. I'm not sure about CBS on 810. I had on the NCAA final four last night, and there is severe break-up watching this.

The TWC cable guy came out, and he's told me my rg59 cable is at fault, and that the house needs to be recabled. Maybe he's right. Maybe the reason for the break-up on CBS has to do with the fast moving action.

But here is the "spooky" part. He says that the channels that I don't receive come into the house on a "different frequency" and that the rg59 cable can't handle this frequency. This makes no sense to me.

Moreover, the guy next door came out and button-holed the cable guy to describe essentially the same problem -- AND HE HAS BRAND NEW CABLES IN HIS HOUSE.

Does anybody know about this so-called "frequency" problem with some HD channels? And what about my rg59 cable? I've seen several threads that say the rg59 is fine.

Thank you.


The box I'm speaking of is the Scientific Altlanta 4250HDC. I personally know that these boxes are not compatible with the HDMI cable into the TV. From another forum, I've learned this is because of some security issue where the cable box has to send a code (I'm thinking this is some sort of a handshake) for the HDMI cable to work. As a result, even if you can configure the SA box so that the HDMI port is working, it comes up with an error if you change channels or leave the TV alone overnight.

When TW can to install this box, they told me this was a "newer" one that will work with the HDMI. It does not. I've learned that the fix for the problem has nothing to do with the age of the SA box. Instead, it is a patch that has to be sent to the box by TW to get around this security handshake. Most of the tech people you talk to do not know of this patch (and various conspiracy theories exist that this is to make you upgrade and pay more).

So in line with the reply I've seen so far (thank you for the input), I'll bet that the same reason the tech guy could not get the HDMI cable to work when he was here yesterday is the same reason that these channels are not working. There is some issue with TW and the SA box that is at the root of the problem.

The tech guy claimed that the HDMI cable would not work (i.e., work at all for *any* channel) because of the rg59 cables in the wall. But this would make no sense to me because, after all, the HDMI cable is nothing more than a conduit. You would expect that if the component wires are carrying the signal, the same signal should pass through the HDMI cable.


It sounds like "smoke and mirrors".

No "conventional" cable systems function in this manner as the installed main cable, amplifiers, etc., typically do not operate beyond a maximum frequency of 520 mHz (well within the capacity of RG59). Even some (uncommon) dual cable systems only carried 300mHz on each cable then used the cable box to do the selection.

Even FIOS does not send content into the home that cannot be handled quite well by RG59.

The single notable exception, of course, is Dish Pro which requires "rated" cables because they send some content at frequencies up to 2,150mHz.

Perhaps the guy doesn't know what he is talking about or is simply trying to sell you an unnecessary cable upgrade.

I'd get on the phone with TW on Monday and get to the bottom of the problem (which your neighbor is also experiencing).
Sounds like a TWC problem.

03-31-2008, 12:30 PM
The guy came out, and he insists my problem is the RG59 cable. I showed him the reply I've received that "no cable system operates beyond a maximum frequency of 520mHZ." He claims this is not true. He says that I'm not receiving ESPN2 because it comes in at 724 mHZ. He says that ESPN comes in at 603mHZ. He says that "I'm lucky to get ESPN with my RG59 that only receives 520nHZ."

I also asked about why I'm seeing so much breaking up with CBS, and this got a different answer that they are "having problems with the signal they get for that station."

I'm in Hilton Head, SC, and this is TWCSC that I'm working with.

04-01-2008, 06:27 AM
Here's a link ---good read


04-02-2008, 08:42 AM
I went out last night, and I purchased a 50' length of RG6 cable at HD with the connectors on both ends. I connected this cable directly from the hub coming into the house and the back of the SA 4250 converter box.


So the cable guy was right, and the link cited by Treker (thank you!) does give an explanation of this.