Problem detecting Clear QAM

I am on basic cable, and my HD television picks up the QAM fine.

When I try to scan for digital channels in Media Center, it finds none.

My tuner hardware is:

Pinaccle 801e with the latest driver (2.3.3.32)

Avermedia M791 PCIe Combo NTSC/ATSC with driver version 6.104.0.5

I can record two channels at a time, and they are fine on analog. However when I scan for the ClearQAM it fails. It also shows nothing if I try to change to a known channel manually (for example 104.2 on my tv eworks, but doesn't display on my system).

Is there a way to know which tuner I am watching? Can I switch to one specifically before trying Clear QAM? What else should I try?

Thanks!

I do have two splitters. One 3 way in the basement where the cable enters the house, two go to TVs and one goes to my computer area.

I just got a Radio Shack bidirectional 1-4 splitter that is in my computer area. One is terminated, the other three are:

Cable Modem
Tuner Card 1
Tuner Card 2

I just upgraded to Windows 7, and hadn't used my HD stick for a while because I didn't have a splitter to give me the extra connection, and I preferred my internal for "neatness"... When I did experiment with it on Vista, it worked fine, but I didn't have the internal tuner hooked up, and less splitting. I will experiment, and determine if I can get what I need by bypassing the last splitter. That will at least confirm the issue.

Am I correct in assuming that my stick should work on Clear QAM even if it hasn't scanned the channel? In other words, if I type in 104.2, it should receive a signal (if it is strong enough) even if it missed it on the channel scan... Since I am going to disconnect even my cable modem for the test, I won't have the connection to go through the whole channel setup.

Also, I think going to the bedroom, the cable was bought in bulk from Home Depot, and it is the right RG type for digital cable (although right now, I forget because I am not at home, is it 6?). Is that a potential issue? I did use the proper connectors and tools to create the length I am using. I wonder if I have it too close to the flourescent lights in my basement...

So many things to worry about.

Ok I installed cable for a couple years. Please return any Radio shack splitter or any "gold plated " junk. Call your cable company and ask for splitters. They will usually just give them to you to avoid having to fix your issues, and they are commercial grade that I haven't been able to find anywhere retail). Another thing to know about splitters, each 2-way splitter will lose 3.5 dB, basically cutting your signal more than in half. Now on a 3 way splitter it gets WORSE! You will have 1 leg that gets cut 3.5 but the other 2 ports lose 7db! If you could run straight from the -3 port to your tuner, and run the less sensitive stuff off of all the other legs, that would most likely help. Another thing, most trouble calls I went to were caused by bad connectors. the number one cause of issues (assuming no junk splitters, amps, etc). look into your connector, if you see metal particles on the white shielding, those can cause "arcing" between the center and the outside, basically making no longer a 75 ohm cable. Also if the center conductor gets nicked while getting stripped, you just caused an issue since higher frequncies run along the "skin" of teh conductor. Also, clip the center conductor just past the barrel, too long of a conductor can cause issues. Also, make sure no staples or ails got pinned into teh cable anywhere. Also, too tight a bend in cable will ruin the impedance, as will any kinks.

Edit: also you are technically better off witha 5-way splitter in the basement, since even though it would have the same loss as 2 splitters, you won't have the .5-1dB loss of each connector in the chain.

Thanks for the input...

I always knew there was loss on a splitter, but I always assumed that all splitters are created pretty much equal. I even thought the bidirectional was a marketing ploy... I knew it would be different on an amplifier.

I was actually thinking of moving my cable modem and router to the basement and then I could clean up my area a bit... and if I just don't watch TV in the basement, I have the splitters I initially got from the cable installation, a 3 way and a 2 way, and I would have everything except for the TV I never watch hooked up.

I didn't realize that the loss was different on different ports for some splitters, so I need to make sure that the best one from the 3 way is going to the computer area. Who knows, that and going back to to a better splitter in the bedroom may give me what I am looking for. Before I moved my TV down stairs, I had swapped out the original 1-3 for the 1-2 when I did some rearranging upstairs, and no longer needed the additional line. I swapped back when I put the unused tv in the basement, and I may have well set it up that the best signal is going to the unused tv where it is needed least.

Darryl Licht said:

Due to the shielding in most RG60 cables should not be interferred with by other devices in close proximity.

Hope you get it going... I love mine!

To save money, I recently gave up my DVR and enhanced digital cable, so I really do miss the ability to record in HD. I will consider swapping cables, along with the splitters as mentioned above...

And I will cross Radio Shack off of my shopping list... although I do appreciate them for sponsoring a pro cycling team. :)

[QUOTE=Little Darwin;586319]

Darryl Licht said:

And I will cross Radio Shack off of my shopping list... although I do appreciate them for sponsoring a pro cycling team. :)

I wouldn't blame Radio Shack, as even "Monster Cable" and various other overpriced splitters are garbage. Especially anything "gold plated". Most people don't realize to get the benefit of gold plating both sides need to be gold plated, anyways. But regardless the gold plated stuff is junk. And yeah for it to not be bi-directional, they would need to purposefully put in a filter to block the return frequencies (assuming they knew what frequencies your service provider used for the return path). I buy stuff at Radio Shack quite often, but mostly capacitors, transistors, etc.

How about the need for terminators?

Here is a blast from the past for some of you who have been around computers since the PC started getting into the networking world...

I seem to recall back in the ancient history of networking (coaxial ethernet) that there needed to be a special terminator on the last system on each coax run.

Is there a significantly increased loss in a splitter if an output is left open? Specifically for the frequencies used by digital cable.

Little Darwin said:

How about the need for terminators?

Here is a blast from the past for some of you who have been around computers since the PC started getting into the networking world...

I seem to recall back in the ancient history of networking (coaxial ethernet) that there needed to be a special terminator on the last system on each coax run.

Is there a significantly increased loss in a splitter if an output is left open? Specifically for the frequencies used by digital cable.

In old networking(token ring style) you needed that terminator to keep the impedance correct. In cable TV, it's not that important as in networking, BUT, you can get interference leak back in and cause issues. It's not the loss you are concerned with. It can especially affect broadband, return carrier data, and used to cause ghosting if you had a strong analog OTA signal near you.

However for some trivia for you, it is VERY IMPORTANT for cable companies to install them on ALL open ports on all of their taps they have on poles and underground because of the leakage that you mentioned. the reason this is because some time ago( I think mid-late 70s but cant remember) there was a commercial airplane that was having major problems and was trying to land in very bad conditions. They were near the airport, and it's system picked up what it thought was the runway, a long straight run of signal. Only it turned out to be a long straight run of residential cable lines. So you can imagine the outcome when it landed. The FCC then wanted to make sure that never happened again. Around my area I can sopmetimes see the helicopters they sound out to test, it's a helicopter witha very large "module" hanging off the front. If you didn't know better you might think it was a camera, and they fly over the power lines.