Jump to content

Welcome to DBSTalk


Sign In 

Create Account
Welcome to DBSTalk. Our community covers all aspects of video delivery solutions including: Direct Broadcast Satellite (DBS), Cable Television, and Internet Protocol Television (IPTV). We also have forums to discuss popular television programs, home theater equipment, and internet streaming service providers. Members of our community include experts who can help you solve technical problems, industry professionals, company representatives, and novices who are here to learn.

Like most online communities you must register to view or post in our community. Sign-up is a free and simple process that requires minimal information. Be a part of our community by signing in or creating an account. The Digital Bit Stream starts here!
  • Reply to existing topics or start a discussion of your own
  • Subscribe to topics and forums and get email updates
  • Send private personal messages (PM) to other forum members
  • Customize your profile page and make new friends
 
Guest Message by DevFuse

Photo

what causes pixelation?


  • Please log in to reply
4 replies to this topic

#1 OFFLINE   bnewt

bnewt

    Godfather

  • Registered
  • 335 posts
Joined: Oct 02, 2003

Posted 28 December 2004 - 03:57 PM

hope that is the correct term
I just installed the Motorola HD101 ota stb in order to receive my local digital channels. On the FOX station, it takes longer for the signal to lock in & before it finally locks in, the picture is scrambled & blotchy. I have also noticed that the same type of thing happens when watching the channel. Just wondering what causes this problem. I live south of Louisville, Ky - 40165 zip code.

********************************************
May God Guide and Guard the USA!
********************************************


#2 OFFLINE   boylehome

boylehome

    Hall Of Fame/Supporter

  • Registered
  • 2,143 posts
Joined: Jul 16, 2004

Posted 28 December 2004 - 06:53 PM

The main thing that causes pixelation on digital channels it poor/week signal. The signal form OTA or for that matter, from satellite is purely digital, and when the signal strength falls below whatever is normal, you get pixelation or nothing. Sometimes if it is an abrupt loss of signal, you will get a frozen frame with a good picture. Multipath is also a problem when it comes to a digital signal and pixelation.

#3 OFFLINE   bnewt

bnewt

    Godfather

  • Topic Starter
  • Registered
  • 335 posts
Joined: Oct 02, 2003

Posted 29 December 2004 - 07:27 AM

I don't think that it is signal strength. All of the local channels are broadcasting from the same location in digital. I don't know about multipath issues. When I tune to the local FOX network the picture shows up but there it doesn't stabilize as quickly or cleanly as the other local signals. I don't know if pixelation is the correct term or not, kind of reminds me of scan disk on a computer, just little blocks in areas of the screen. Last night I was tinkering with the setup. I have the ota antenna fed into a distribution amp which then feeds other tv sets. Last night I by passed the amp and fed the signal directly into the stb. I switched channels several times and did not have this problem. I then switched out the amp to a radio shack one that had a fm trap switch. Initially, I had the same results, then I changed the fm trap switch & did not have the problem. Could the signal be "over amplified"? I thought about going to Radio Shack & getting a fm trap today & check it again tonight.

********************************************
May God Guide and Guard the USA!
********************************************


#4 OFFLINE   boylehome

boylehome

    Hall Of Fame/Supporter

  • Registered
  • 2,143 posts
Joined: Jul 16, 2004

Posted 29 December 2004 - 07:35 AM

Yes, your signal in fact, could be overamplified and that can be just as bad as a very poor signal. It may be worth while to check your signal strength meter for the channels, with and without the amplifier, to see it your assumptions are correct.

#5 OFFLINE   bnewt

bnewt

    Godfather

  • Topic Starter
  • Registered
  • 335 posts
Joined: Oct 02, 2003

Posted 29 December 2004 - 12:07 PM

My stb does not give a numeric value for the signal strength, it shows colored blocks. The signal strength looks to be the same with & without the amp.

********************************************
May God Guide and Guard the USA!
********************************************





spam firewall