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Noise Bars? Need Help

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Anonymous
June 28, 2005 11:32:20 AM

Archived from groups: alt.tv.tech.hdtv (More info?)

Are noise bars what we call the subtle yet annoying horizontal lines rolling
through colored areas of the screen, most notably all-white or deep blue?
My HD CRT has this problem and it's driving me crazy. Everything I've read
says it's a "grounding issue" and I should disconnect all equipment, then
reconnect one-at-a-time to find the culprit, then use an "isolation
transformer". Can anyone explain this to me in layman's terms... I have the
TV, DVD, DVR & Xbox hooked into a Monster surge protector which in turn uses
one outlet.

Thanks,
Aphelion

More about : noise bars

June 28, 2005 4:01:11 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

In article <827we.42299$fp6.30883@twister.nyroc.rr.com>,
sonship@twcny.rr.com says...
> Are noise bars what we call the subtle yet annoying horizontal lines rolling
> through colored areas of the screen, most notably all-white or deep blue?
> My HD CRT has this problem and it's driving me crazy.
>


1. I found a bad video cable was causing mine. Try swapping.

2. It *could* be coming from some sort of ground problem. ("Ground"
isn't always the same on all things. Slight differences can cause
problems.) Try disconnecting every input source, then connecting one-by-
one.

If you can isolate the problem, then you are half way there.
Anonymous
June 28, 2005 4:12:52 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

Aphelion wrote:
> Are noise bars what we call the subtle yet annoying horizontal lines rolling
> through colored areas of the screen, most notably all-white or deep blue?
> My HD CRT has this problem and it's driving me crazy. Everything I've read
> says it's a "grounding issue" and I should disconnect all equipment, then
> reconnect one-at-a-time to find the culprit, then use an "isolation
> transformer". Can anyone explain this to me in layman's terms... I have the
> TV, DVD, DVR & Xbox hooked into a Monster surge protector which in turn uses
> one outlet.
>
> Thanks,
> Aphelion

You have a ground loop problem. Since all the AV boxes are connected
to the same surge protector, my guess is that your RF input line - be it
from cable or satellite co-axial hookup - is not well grounded. I had
the same problem with my Comcast cable hookup and my solution was to run
the RF cable line through the surge protector which had RF input/output
connectors on it. That grounded the RF line to the same ground as the TV
and the problem was solved. If your Monster surge protector has RF
connectors on it, try that first. If it doesn't, then you could try to
ask your cable company to properly ground the cable line running into
your house.

If you have satellite, connect the set top box to the same surge
protector as the rest of the gear. Beyond that, call your satellite
company. The antenna line may not be properly grounded.

Alan F
Anonymous
June 29, 2005 5:19:23 PM

Archived from groups: alt.tv.tech.hdtv (More info?)

On Tue, 28 Jun 2005 07:32:20 GMT, "Aphelion" <sonship@twcny.rr.com>
wrote:

>Are noise bars what we call the subtle yet annoying horizontal lines rolling
>through colored areas of the screen, most notably all-white or deep blue?
>My HD CRT has this problem and it's driving me crazy. Everything I've read
>says it's a "grounding issue" and I should disconnect all equipment, then
>reconnect one-at-a-time to find the culprit, then use an "isolation
>transformer". Can anyone explain this to me in layman's terms... I have the
>TV, DVD, DVR & Xbox hooked into a Monster surge protector which in turn uses
>one outlet.

You haven't included enough specifics about your setup.
(Cable?, Sat?, OTA?, number of outlets?, AV components?, etc)

A pair of slowly scrolling white noise bars are called hum bars.
They occur when too much AC current is traversing the coax shield at
some point in your setup or cable service. (1/2 amp for RG-6, ~4amps
for .75 inch coax). Reduce AV components & TV power plugs to a
single outlet. Disconnect all other jacks. Are hum bars still
present?

Does the noise occur on all signal sources.. or just one?
Which ones?
Is local playback from VCR/DVD affected?
!