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UPS Video Interference

Posted by windslam (My Page) on
Fri, Jan 1, 10 at 18:49

I hope someone has an answer,

I recently connected an Uninterpretable Power Supply from Hewlett Packard (model 400VA) to my big dish satellite system (4Dtv). I am now getting video interference caused by the UPS. I rerouted all cables so they will not be near the UPS box or wiring. I also located the UPS box well away from the receiver unit and analog television. It helped some but I still get interference.

Anyone know of a solution or filter I can use to eliminate the problem?

Thanks,
Windslam


Follow-Up Postings:

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RE: UPS Video Interference

The interference may be on the output of the UPS power line ...

Most UPS's are pure square wave or "Modified Sine Wave" (stepped square wave)

The power supply in your equipment may not like that.

You could look for a "Pure Sine Wave" inverter or UPS


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RE: UPS Video Interference

regus,

Thanks for the info, it makes a lot of sense since the interference is only when the UPS is plugged in and the equipment is plugged into the UPS. This is not HP's top of the line UPS so I suspect the modified sine wave would be less expensive than a full sine wave unit. At least now I know the cause!!! Do you happen to know if there is a filter I could use on the video output which might filter out the frequency interference in lieu of replacing the UPS?


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RE: UPS Video Interference

no filter can do that ...


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RE: UPS Video Interference

You might be able to try one more thing. Check all of your coax connectors. If you have the screw on type, they can cause you more grief than the crimp type over time. If you are using more than 3 television sets, there's one last solution. Although the 4dtv receiver is digital, the output through the coax is analog. The RCA connectors are the digital outputs. It sounds as if the digital interference from the UPS is doing as REGUS points out, the digital interference is bleeding into your outputs.

AFTER you have checked and tightened all your coax connections, install a DISTRIBUTION AMPLIFIER. I recommend an inexpensive unit from Radio Shack for about 50 bucks for a 1-In/4-Out Bidirectional. I recommend this one because it has a gain control that allows you to control 54-1000 MHz. When you connect this, you can increase the gain (by turning a small knob) until you have a good picture. Stop there and your problem may go away because you are blocking any higher frequency interference. If you still get the interference, it's of the lower frequencies which are infiltrating your signal. I doubt your problem is of the lower frequency. I would bet it is of a higher one.

Please post back and let us know how you made out.


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RE: UPS Video Interference

I believe that the "interference" isn't on the Audio, Video, nor RF signal,
but rather inside the TV video ciruitry itself from the "stepped-sine-wave" UPS power frequency.


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RE: UPS Video Interference

It may not even be the "stepped sine wave", but rather the cheaper square wave ...


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RE: UPS Video Interference

EURICA !!!!!! Irisman, you were right on the money. I checked my connections and found one that every time I pushed on it, the signal would go completely out. I put a new crimp fitting on that one but still had those moving dots on the screen. We have a Radio Shack within walking distance so I boogied down and picked up that amplifier you recommended, hooked it up and plugged it in. At first I was discouraged because I still had some interference. When I adjusted that knob thing to the Minus" direction, the picture cleared right up. What would have happened if I kept turning it?

Thank you and REGUS for all your help and info!! Have a great new year!!!!!!


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RE: UPS Video Interference

If you would have kept turning the knob to the "minus" direction, you would have eventually reached a point where there was no amplification of the signal. If your signal was already strong and your connections good, you probably wouldn't notice a change. If you rotate into the "Plus" direction, you will strengthen the signals until the picture starts showing interference. Interference from just about anything that radiates a signal would bleed into your video signal as interference. I've seen instances where a nearby wall plug in type timers cause interference.


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RE: UPS Video Interference

lol,most problens with the 4DTV's are when some one moves it and the wiring gets messed up,good to hear you found the problem!Do you also have a DVB reciever?


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RE: UPS Video Interference

No, just the 4dtv. I was looking for a reasonably priced mpeg unit. I'm in a good reception area and my off-air antenna picks up quite a number of channels. Once I realize that at 5am all I'll get is info-mercials, I'll order an mpeg box from Sky-Vision. Looking at the programming for mpeg2, I should get 5,000 more channels with not much to watch. But, it'll be fun channel surfing!!


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RE: UPS Video Interference

If you can get your hands on a hd reciever like one of the cool sats(8000/8100 series that were used for hacking before) lot of them for sale now, you will have plenty to watch plus H.D and DVBS-2.Or a pansat 9200 with the official DVBS-2+ board.If you do go with Skyvision make sure you get the add on board or you will not get the DVBS-2 feeds(they are pricey and say it is optinal),and believe me you will need it if you want to watch T.V in the near future(for free).Happy hunting!!!!!!!!!


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RE: UPS Video Interference

Good info!!! Is SkyVision more pricey than other suppliers? I've never dealt with any of the others. I was using Sky Vision before there was an Internet so just because I trusted them, I continue to use them. Are there other trustworthy suppliers that offer better prices on that stuff?


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RE: UPS Video Interference

If you live in the U.S.A Skyvision is pretty good, and if you find a product at a better price at another reputable supplier ,they usually will price match.If you are in Canada ,RPS Satellite is the place to go (and also will usually price match).


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RE: UPS Video Interference

You should look for a "Pure Sine Wave" inverter or UPS.

Here is a link that might be useful: Los Angeles Appliance Repair


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