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Topic: Optimum TV trouble
Joined: Feb 7, 2008
Posts: 13
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I am having some trouble with the signal I get from my HD cable box from Optimum TV. It is a Scientific Atlanta box. I have it hooked up via component cables. Overall first immpression of the picture I get is impressive. However, I noticed a strange distortion. It is almost like the old ghost scan lines you used to get in the old days of cable tv. I am getting a very subtle green horizontal line, and a purple horizontal line, which extents from all the way to the left to all the way to the right side of the picture. You have to strain to see it, and it becomes more apparent when the screen is gray as you change from channel to channel. The lines scan their way from the bottom to the top in about 8-10 seconds and they start again. It does this whether I hook it up direct from the cablebox to the PJ as well as when I run it through my Denon AVR-1908.
I tried hooking the cablebox to the PJ via HDMI, but I get no picture at all that way. It says HDMI blocked, copy protected. I don't know what to do. Does cable suck? Do I need Direct TV or FIOS? Should I give up on cable?

Does anyone have any experiences like this?
Joined: Mar 28, 2005
Posts: 13,165
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Look on Google for information on ground loops. This is the most common issue, and will go away completely if you hook up via HDMI. You can run directly from the cable box to the projector via HDMI. There are any number of cable boxes that have SERIOUS issues with receivers and passing HDMI on to the projector. You may want to try a remote controlled 2x1 HDMI switcher that doesn't run through the receiver, such as those from

I've seen almost no ground loop issues with HDMI - which is a huge plus to that digital format.

The ground loops can be incredibly difficult to pin down and are often related to the cable not being properly grounded, or on a different potential than the rest of the A/V system. You can get surge supressors/power conditioners that have cable in/out jacks which can help to get rid of the lines, but not as cleanly as running HDMI will do.
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