Machine noise in picture? –Weird Problem

[FreeBSD4me]

Not sure why, but since I completed my configuration and moved it downstairs, I’m now noticing picture noise in the background. This noise is in the form of small lines alternating virtually, and to some degree horizontally, and is most noticeable when the screen goes dark, or in a dark scene. The more action /light that’s is a scene, the more the noise momentarily disappears. This is appearing on my TV btw..

It’s no doubt machine noise, as when I go to a raw video feed from the satellite box, it’s totally clean. I switched video cards to see if that would help, but no luck. I moved the wires around to see if the noise would fluctuate, but no change at all.

Clearly, the noise appears to be originating from the PC/ TV-Out, but how? Is it the hard drive perhaps? It’s a fairly new machine. An AMD 2200 Mhz; Western Digital HD, GeForce 5200, etc. Pretty standard config...

I’ve seen this type of noise before from crappy cables, but everything I’m using here is pretty decent. Has anyone seen this before? Since it’s not a software problem, there’s not a whole lot of adjusting that can be done. This is a drag, as it adds extraneous background noise to what otherwise is a very nice picture. Reminds me of that annoying AC hum present in some audio systems. Any insight here would really be appreciated.

Many thanks,

Dave

[FreeBSD4me]

Possible problem / theory:

Looking over the config again, I noticed the ‘included’ S-Video to composite cable looks a little lame –not too well shielded. The TV I’m using is an 8-year old Sony 27 inch. I noticed that if my monitor is within 12 inches of it, it’s sporadically thrown out of sync as the result of a considerable amount of electro magnetic energy emanating from the TV.

I just wonder if my thin S-Video to Composite cable is picking that up, since it’s so close to the back of the set. If it was picking this up, that may be the cause of the screen noise I’m seeing. Is this a possibility?

Thanks,

Dave

[stanger89]

Probably, at least that's the first thing I'd check.

[FreeBSD4me]

Thanks Stanger89,

I’ll grab a better one. Oh… Just in case you’re interested on what happened with that serial port on the back of the Satellite box, after 2-days of trying solutions/ hacks on here, I finally broke down and called Starchoice. Guess what… The tech sort of laughed when I asked him to enable it, and explains to me that it’s an HDTV encoder/ signaling port? In fact, that’s the purpose it serves on most of their boxes. Other than a DTV box, he wasn’t aware of anything from Starchoice that would serve that purpose, other than ‘maybe’ their highest end box, but even then he doubted it.

Just thought that may be useful to you, or anyone else trying to interface with one of these boxes. They should call first and verify the purpose of this port, before chiseling away at it for an eternity

[SHS]

One other possable you may be seeing AC hum bars are usely caused a bad ground loop which usely a difference in ground between two sources.
With cable that sometime can eazy be fix in most case by a simple and cheap solution using a couple of 300-ohm to 75-ohm transformers.

[FreeBSD4me]

That’s one very distinct possibility that came to mind, but I’m running a Satellite box. I totally decoupled everything from the box, so that all that was left, was the PC feeding composite into the TV set. Yet… I’m still seeing those lovely little lines in the background of dark scenes. You know what it looks like? Have you ever seen what happens when you transmit from a CB or other type of two-way radio too close to a TV set? You can see background distortion spiking down the TV in the form of small lines –that’s sort of what it looks like, or at least the closest description.

All I need to do is view the desktop, (set to black background) on the TV, and you can see the lines. If you look beside the icons, you can see brighter lines that go across the screen from them. Funny though… If I pop up a dialog box, the lines disappear. When I shut the dialog box down, it takes about 3-seconds, and the lines begin to reappear again.

ARRGH… I have a feeling this is going to be a real pain to fix. What do you think?

Thanks,

Dave

[FreeBSD4me]

Got it, or at least what appears to be it…

It’s that piece of poop S-Video to Composite cable included with the 5200. I plugged this cable directly into my satellite box and out to the TV. Sure enough, NOISE… and lot’s of it, but more pronounced being plugged directly into the S-Video on the box. Makes sense, since this cable is the width of a pubic hair. It’d be nice if they’d either A: Supply the correct TV-out path cord, or B: Be upfront and let you know they’ve bundled a junk TV-out cable, and that if you wish to use TV-out, you’ll need to purchase a real one

[stanger89]

:rofl

Not the problem, the description.

FWIW, it's generally assumed that bundled cables are crap, and a nice surprise when they aren't

[FreeBSD4me]

Haha… I was trying to convey my disappointment in the politest terms possible. What you said is true though –since when do most A/V manufactures of any sort ship HQ cables with their products?

Thanks again,

Dave