Forum Groups
  All forums
    Help & Feedback
      Questions
      Work in progress
      Finished Art
      Non-Max related
    Community
      Offtopic
      News
    Hardware
    Photography



Maxunderground news unavailable

 
First page  Go to the previous page   [01]  [02]  Go to the next page  Last page
 
JVC TV
show user profile  MrCaseStudy
I brought a new JVC TVthe other day, i when playing dvds thought my scart lead the screen seems to have dark vertical lines on it! its kind of anoying because the picture is not of great quality, dont suppose anyone has the same problems?
read 728 times
7/13/2013 10:21:44 PM (last edit: 7/13/2013 10:21:44 PM)
show user profile  Dmaxer
is it CTR of LCD or a plasma tv ? is it only when you play a Dvd ? is it ok when you watch Tv ?
I had an old CRT Tv that would show white lines across the screen , I fixed it by turning down the back scan inside, but Ive not seen dark lines.


read 719 times
7/13/2013 10:52:11 PM (last edit: 7/13/2013 10:52:11 PM)
show user profile  MrCaseStudy
its an LED tv

this is what it looks like

see the lines on the background?
read 711 times
7/13/2013 11:10:25 PM (last edit: 7/13/2013 11:10:46 PM)
show user profile  Dmaxer
that looks like interference to me how long is the cable ? if its very long try a shorter one but even if it is short have you tried another cable ? it could be bad screening in the scart cable as this could make it pick up interference from a mains cable or some other form of Rf interference from a transformer or even a switch mode PSU, have a look and make sure the scart is not sitting parallel to any main cables or to close to any transformers.


read 701 times
7/14/2013 12:07:53 AM (last edit: 7/14/2013 12:09:13 AM)
show user profile  MrCaseStudy
Well i have a long cable due to the placement of the telly and the plugs etc, the connectors at the back of the telly are all close together, aerial hdmi scart lead etc.
read 664 times
7/14/2013 5:33:26 PM (last edit: 7/14/2013 5:33:26 PM)
show user profile  Dmaxer
as I siad that looks like interference dude and the fact that you say you have a long cable makes me sure thats your problem , you may want to get a cable with better screening.


read 659 times
7/14/2013 10:14:23 PM (last edit: 7/14/2013 10:14:23 PM)
show user profile  Dr. Jim
hmm.....RF interference on a LED screen?...? This is a digital signal...interference would not manifest itself like this.
It does look like traditional analog CRT interference for sure...........but this couldnt happen on a digital signal.
read 622 times
7/16/2013 8:56:16 PM (last edit: 7/16/2013 8:56:16 PM)
show user profile  Dmaxer
Dr Jim your forgetting one thing dude , the Signal in a scart cable is not digital its analog so yes ...interference could manifest itself like that and I would say thats just what its doing.
the codec chip in the Tv will convert the signal to digital before it gets to the LCD driver but any interference on the analog side will also get converted and passed to the driver.


read 618 times
7/16/2013 10:01:55 PM (last edit: 7/16/2013 10:01:55 PM)
show user profile  Dr. Jim
Correct.....but once it is converted to digital it wont be that type of wavy line oscillating interference.
It will be blocky/glitchy artifacting. Same reason none of the traditional analog interference appears on new LCD/LED tv's....

That is what digital signal interference would look like.
There is no way the ADC in the tv would convert the interference into nice little diagnol lines.....just doesn't work like that.

? Am I wrong?....You got me curious now...
read 616 times
7/16/2013 10:04:42 PM (last edit: 7/16/2013 10:17:42 PM)
show user profile  Dmaxer
why wont it ?? think about it this ,, if theres no way the DAC in the tv would convert the interference into nice little diagnol lines how can that same Dac draw nice diagnol lines when your playing a game on your xbox ? the Dac and the codec wont always know that the interference is not part of the analog signal and this can be very true with the cheaper units. I know cos Ive seen it myself. Ive worked with digital and analog equipment for years in tv and audio studios for years now and I can tell you for sure we still worry about interference when it comes to long cable runs .
dont think just because its digital its going to be clean , theres still a lot of ways the data can get screwed up.


read 609 times
7/16/2013 10:20:18 PM (last edit: 7/16/2013 10:21:22 PM)
show user profile  Dr. Jim
Well..an Xbox would draw little lines because it was told to ;)

Hmm...the various types of analog artifacts that are seen on CRT are caused by the analog signal interference affecting the beam scanning and magnet involved with beam scanning in a traditional CRT. Rolling, lines, ghosting..etc....all due to the 'reaction' of the way a CRT operates to an impure (affected) signal.

A digital TV has no magnet, doesnt 'scan' the screen...etc. Totally different operation. When it receives a signal that is impure (affected/jacked up) it's reaction will digital artifacting/glitching..etc.

I can only state my thoughts at this time,....I gotta do some research here. Not saying I don't believe you....but I need to read some tech here on how this would be possible. Very interesting......

Edit: Just did some reading on SCART (hadnt heard of it).....hmmmm...so I see your point...this is 100% analog....until it hits the TV.....hmmm.....
read 601 times
7/16/2013 10:27:36 PM (last edit: 7/16/2013 10:34:56 PM)
show user profile  Dmaxer
well we could go on all night believe me lol , mate but I think your missing the point ,

A digital TV has no magnet, doesnt 'scan' the screen...etc. Totally different operation. When it receives a signal that is impure (affected/jacked up) it's reaction will digital artifacting/glitching..etc.

yes your right the operation is not the same as a CTR but again your missing the point mate the signal is analog it can get distorted and you must remeber the Tv circuit will alway do its best to reproduce the picture. you do need to read up on this stuff mate .I mean your going down the rabbit hole way to much, theres untold ways interference can work its magic in the analog world when it comes to Tv's be it CRT or LCD , my main point is that MrCaseStudys picture looks like interference and the long cable he is using is a scart and that is analog , so if it looks like a duck and sounds like a duck I bet you £5 its a duck , simple as that , Im not in anyway digging at you mate or trying to get one up on you but Ive been working in this feild for over 25 years so I do think I know a bit about it ..
anyway lets hope he sorts it in the end :)


read 592 times
7/16/2013 10:48:14 PM (last edit: 7/17/2013 1:03:20 AM)
show user profile  horizon
I got a fairly new samsung LCD and still have analog TV for legacy reasons. It is connected with the old coaxial cable.
The noise it gets is identical to the one my old CRT has minus some smart noise removal the new TV does.

So... doesn't matter what the destination is, the signal is analog, interference is analog, so the lines will look analog


read 580 times
7/17/2013 9:32:34 AM (last edit: 7/17/2013 9:33:38 AM)
show user profile  Sir_Manfred
Thaaaats right.
Analog signal interference come up as these lines.
Digital signal interference come up as a scrambled picture with artifacts.

So yeah. It's most likely the SCART.



Visit my Portfolio
http://www.Freds3D.com

read 571 times
7/17/2013 10:51:31 AM (last edit: 7/17/2013 10:51:31 AM)
show user profile  MrCaseStudy
so what do you think my next step is? i cant really make the cable shorter as it wont reach the dvd player, im limited with sockets you see
read 551 times
7/17/2013 4:31:23 PM (last edit: 7/17/2013 4:31:23 PM)
 
First page  Go to the previous page   [01]  [02]  Go to the next page  Last page
 
#Maxforums IRC
Open chat window


Support Maxforums.org