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Discussion Starter · #1 ·
After a two year wait, I had installed last week a RCA oval DirectTV dish, an OTA with a rotor, and two receivers -- a RCA ultimate tv set and a Panasonic TU-HDS20.


I've noticed that on both of my TVs there is a flickering wave of something -- like interference -- on the picture. When the dss receiver is turned off, the tv screen is black but I can see an undulating pattern of slight whiteness rolling off the screen.


Any help would be greatly appreciated. I had this professionally installed.
 

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LG 55" C9 OLED, Yamaha RX-A660, Monoprice 5.1.2 Speakers, WMC HTPC, TiVo Bolt, X1
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Sounds like ground loop hum. Best advice is to have an electrician check all outlets to verify proper wiring.




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"better living thru modern expensive electronics"

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Discussion Starter · #3 ·
What do you mean by all outlets? All the outlets in the house? Or just the ones the new equipment is plugged into?
 

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Check all the outlets your system is using. If you find a bad outlet, then, for safety reasons, you should check the whole house.


If you have an AC voltmeter you can do it yourself. While facing the outlet with the "inverted-U" on the bottom, the voltage between ground (the inverted-U) and the LEFT power slot should be less than 2 volts and stable. The voltage between ground and the RIGHT power slot should equal your line voltage (about 115v). If the voltage is reversed from the above, or if there is no voltage or wandering voltage, then that socket is wired incorrectly. You can check power-strips the same way.


All the recepticles used by your system need to be the type that accept 2-prong plugs one-way only (with the "wide" prong to the left). All your equipment should have either grounded plugs or 2-prong plugs that only fit one-way.


Don't stand in a puddle of water while making these measurements! If you're uncertain about any of this call an electrician


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- gridleak... biased toward HD
 

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I'll try to do some guessing here. The RG-6 cables run through a grounding block somewhere between the antennas and the receivers. That block is probably connected to a water pipe or copper stake driven into the ground. The shield on the RG-6 carries that ground through to the dss receiver. Your system is probably grounded through one of the power receptacles. A significant voltage difference between the two grounds would produce a ground-loop current.


Try disconnecting the RG-6 cables and see that stops the pattern on your black screen


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- gridleak... biased toward HD
 

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Discussion Starter · #6 ·
Thanks to both of you for your help. One more question -- if the banding is a new phenomenon that coincided with the installation of my DSS system -- I never had it when I just had cable -- is it not a certainty that it has something to do with the installation. Or could it have been a pre-existing condition (I suddenly sound like a HMO) that didn't show up until I had the DSS installed?
 

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Or you can also purchase the Monster reference power center.

With this unit it will clean all dirty ac power. Chances are

your'e picking up noise, interference and ac power "pollution" from a variety of sources that share the power lines running from your utility to your home.

Adding clean power technology is one of the best ways to enhance your home theatre's performance.

The Monster power HTS1000 OR HTS2000 are very good products.

visit : www.monstercable.com


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PeterDz
 

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Discussion Starter · #8 ·
Thanks, but I don't think a power cleanser will work here. I have a Niles unit connected to my system and it has the same problems as my other system that uses only a simple power strip. This was never an issue before I got the DSS system.


Gridleak -- I bought a multimeter at Radio Shack and have been poking the two ends in various outlets. So far I'm not electrocuted. And most measure 116-117 so I assume that's an Ok reading.
 

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I think he meant between ground and neutral(wide slot). I measure about .16 volts. If there in no voltage, your socket is not grounded. If it reads 110/120V then your wires are crossed.


I too am tracking down some banding on the screen that has shown up after installing satellite. I pulled all the grounds off the dish and cables but no change. I am going to try connecting the DVD to the TV with everything else disconnected to rule out a TV problem.


Glenn


[This message has been edited by Glenn_L (edited 05-29-2001).]
 
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