Electrical Line Noise and Home Theater

[Bob]

Hi,

I have a vertical line crossing my TV screen that's fairly visible during darker scenes of a movie. I think it's static or noise on my electrical line, because when I unplug my satellite receiver, the line goes away.

I read up on this on the net and it appears that a good powerbar/surge protector with proper noise filtering features should do the trick.

In my shopping, I have come across the following options, an APC SurgeArrest 11 plug power bar, that "absorbs line static, noise and small spikes, EMI/RFI Noise rejection (100 kHz to 10 mHz): 60 dB" for $22 at Costco or the Monster HT800 that features their "Clean Power" solution for $139.

APC product:

clean power: to -> Clean Power Flash Module

Now my obvious question, should I spend the extra bucks on the Monster solution if in the end it does the exact same thing (give or take) as the 1/5th the price APC product? I can't find any further literature on the Clean Power thing, but I'm wondering if it just does the same filtering, maybe a bit better, then the APC one and they're simply giving it a jazzy name, fancier package and selling it for a whole lot more? Will I really see a difference in terms of video/audio quality between the two?

By the way, I know this isn't a home theater newsgroup, but I figured the folks on this NG would know more about home wiring, electrical questions, etc. and that you would be less fanatic about your home theater solutions then in the specialized newsgroups where they will most certainly tell me to get the more expensive product.

[n_o_s_p_a__m]

As a semi audio enthusiast, and a user of APC battery backups for my computer business, I would recommend first trying the APC product. If it doesn't work, return it and buy the Monster product. Or, buy both and return the one that doesn't work. You will know in 5 minutes whether it works or not, so there's nothing to lose (unless you buy from somewhere that doesn't have a decent return policy).

-KJ

[No]

Here is another one to look at

I would also make sure you sat reciver is grounded as per mfg's instructions. That may do it w/o spending hardly anything!

[jstp]

This one is easy. Just buy the $22 system. If it doesn't work, just return it and buy the more expensive system. If you can't return it, you're only out by $22, no big deal.

[w_tom]

If anyone recommends a product from Monster Cable, then save yourself - run for the hills - every man for himself! Notice how irresponsible that protector recommendation; based only upon total technical ignorance - and maybe greed.

A surge protector claims noise reduction. Then we look at the specifications - especially the numbers. Reduction so trivial as to be virtually zero. But those who recommend like an electronics salesman cannot be bothered to first learn basic technical facts. They hope you never ask for numbers.

Want to increase AC electric line noise into that system? Install a computer grade UPS. In battery backup mode, the noise will be maximum - a good test of the noise reduction that must be part of your existing satellite disk system. When not in battery backup mode, UPS connects electronics directly to AC mains where electricity is cleaner.

Address the problem at its source - the receiver, antenna, or (start here) > I have a vertical line crossing my TV screen that's fairly visible

[Mark]

if it is VERTICAL line it is probably NOT related to power....

does it drift slowly across the screen?

I would guess it is the satellite video signal somehow leaking over....and you see the horizontal sync pulse...

what if you unplug the video connection from the sat to the tv?

Mark

[Bob]

Hi, it is a Vertical line and yes it does drift slowly across the screen.

I haven't tried unplugging the video connection from the sat yet, will try that tonight, I have however tried to unplug the sat receiver power cable and the problem does go away.

It's only really noticable during dark scenes of a movie (from the DVD player).

What do you suggest?

The Monster website with their "Clean Power" add do mention the vertical line problem... I'm thinking I might follow one of the previous poster's suggestion and just buy, try it and return it if it doesn't fix the problem.

[w_tom]

Monster product is about as honest as those WMD claims. Forget about them. Start with the dish system - the receiver, the LNB, and especially with the cable between dish and receiver. Fix the problem at its source - not with some marketing scam. Monster Cable has a long history of selling on myths. They do it by pricing their products excessively - which gets store salesmen to hype their products even more.

How to create the dirtiest power for test purposes. Run the dish system > Hi, it is a Vertical line and yes it does drift slowly across the > screen.

[Art Greenberg]

Are you using RF on a VHF channel between devices? Like out of the SAT receiver, or your DVD player? In the "old" days, a moving vertical line would unambiguously indicate co-channel interference, like a broadcast signal leaking into an RF distribution system.

If you're running baseband video around, look for a source of 15kHz noise that could be getting into the video. You may have a bad video cable. Since its moving, it is not due to a problem in the video display itself (a non-moving, ragged vertical line could indicate arcing in some portion of the horizontal deflection circuit of a CRT-based display). Do you have more than one video display? It could be noise from one getting into the other, but in this case the vertical line would move *very* slowly, if at all, especially if both displays are displaying the same video.

If you are using exclusively digital connections (DVI, HDMI), then this noise may actually be originating in the DVD player or SAT receiver, or perhaps on the inputs to the SAT receiver. Some SAT receiver systems use 18kHz or 22kHz signalling to switch LNB polarity, but if your interference is related to that, it would not be a slowly moving vertical line.

[Mark]

whatever switch is being used to select one video source or the other does not have enough isolation and you are seeing a little of the other video leaking over onto the video you are trying to watch

A suggestion is to turn off the other video source when you are not watching it.

Mark