Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[mv6copcar]

un-related to cars.

Got an issue with my TV. I've got these lines scroling up the screen, been told its call 'hum' caused by differing voltages in the grounding cables around the TV and componants,(sky box, dvd,wii etc)
I've moved all the video cables away from any mains cables and made sure they don't cross eachother, but still no different.
It's more noticable when theres dark/black screens shown, even watching the footie,the green of the pitch shows the lines quite clear.

I've earthed all equipment to the same ground.

I can't seem to find any type of 'ground loop' isolators anywhere!!

Anyone else have this issue / had this issue?

Cheers  

[Jimbob]

No, but have had other issues when devices like washer / dryer / heating / shower turn on or off.

They used to upset an old DVD player, cause PC issues.

Sorted them all by using these Surge / Spike / RF protection extension leads, Belkin and a few others do em....
Sure most the claims on the box are rubbish, but did solve my interference issue.

May be worth a try

[Marks DTM Calib]

No, but have had other issues when devices like washer / dryer / heating / shower turn on or off.

They used to upset an old DVD player, cause PC issues.

Sorted them all by using these Surge / Spike / RF protection extension leads, Belkin and a few others do em....
Sure most the claims on the box are rubbish, but did solve my interference issue.

May be worth a try

Thats sudgesting a wiring fault somewhere!

Or if a single device then an issue with the internal suppresion.

As for ground loops...I am not convinced.....does it still occur if viewing say an RF video source (video recorder), does it do it on all channels, is it only on aux or scart?

[mv6copcar]

I've tried unplugging all cables and just connected the sky to the tv, much better but still there, then i plug the dvd player in, getting worse, plug the wii in, worse still, and with the cctv plugged in as well, totally unwatchable (constant bars rolling up picture)
PS i'm using a 4way remote controlled RCA selector to switch between different inputs.
the TV's mounted on the wall with a single Video RCA connected, Audio L+R RCA's go to the surround sound.

[mv6copcar]

And everywhere i look on the web i find 'ground loop' isolators for audio, but none for visual..........must be something out there

[Martin_1962]

SOunds like poor cables to me and you should be using a Scart selector as RCA is rather poor anyway

[mv6copcar]

SOunds like poor cables to me and you should be using a Scart selector as RCA is rather poor anyway

cables are 'cambridge audio visual' screened and gold plated, and the reason for rca is that the wii has triple phono output, the cctv has bnc (with convertors to phono) and the sky has the option for rca, so it was easier.

would using a scart selector with 2scart-to-rca adaptors be better?

[Marks DTM Calib]

Agreed, sounds like poor cables....and just because you have some over rated cambridge audio gold plated, million strand conductor, oxygen free copper stuff......dont assume they have a good screen in them.

[Gaffers]

Are you sure the ground in your building hasnt been knocked out?  

[mv6copcar]

Are you sure the ground in your building hasnt been knocked out?  

  checked that, and its ok. good job too ay!

[Gaffers]

Are you sure the ground in your building hasnt been knocked out?  

  checked that, and its ok. good job too ay!

phew!  

[mv6copcar]

Agreed, sounds like poor cables....and just because you have some over rated cambridge audio gold plated, million strand conductor, oxygen free copper stuff......dont assume they have a good screen in them.

well i can see what your saying but i've tried to get the best gear i can, in total all the cables i needed came to £185, been re-asured by the shop that sold them to me it wont be caused by the cables.

am pulling my hair out at the mo!!!!!!!

[Gaffers]

Have a look here:

http://en.wikipedia.org/wiki/Ground_loop_(electricity)

[mv6copcar]

Have a look here:

http://en.wikipedia.org/wiki/Ground_loop_(electricity)

cheers mate, but been there befor, and yet again they talk about a loop isolator. i've earthed all equipment to the same ground.
just got to find where to get these isolators!

 :-/

[Gaffers]

Have a look here:

http://en.wikipedia.org/wiki/Ground_loop_(electricity)

cheers mate, but been there befor, and yet again they talk about a loop isolator. i've earthed all equipment to the same ground.
just got to find where to get these isolators!

 :-/

If you scroll down it talks about low amp devices causing an imbalence of ground voltage which could be causing the issue.  If you have a different screen try using that and see if the results are similar.