Wavey Waves!?!?!

Forgive this, as I posted a similar thread with a different title with little response, but i got a problem with an occasional 'wave' going up my plasma screen about once every 15-20 minutes - starts at bottom and moves up the screen in about 3-5 seconds and disappears. Doesn't seem to matter what source (Time Warner or DVD) or what input signal to tv (s-video or component). The cable and DVD are both connected to receiver (HK AVR-635) via S-video. Has anyone else ever experienced anything like this? I have two surge protectors for all my equipment and I believe they are in parallel into one outlet. Could this have anything to do with it? Any suggestions. I am pretty sure it is not a cable issue and not something with the tv.....also, very unlikey, but I also have a garage door monitor receiver near the tv so I can monitor my garage door...a transmitter mounted on the garage door sends a wireless signal to the garage door sensor reciever and it has two lights to indicate whether the door is open or shut....is it EVEN remotely possible that the signal that the sensor for the garage door is sending to the garage door sensor reciever is causing some interference with the plasma!?!? I believe the signal is continuous....

When I read your first post, I tried to come up with possible causes--everything from power supply failure to vertical sync problems to relative positions of your cables, to moire patterns, you name it. But what problems occur at such long intervals in components? None spring to mind. You mention surge protection but not powerline conditoning. Does anything that you own automatically power up at 20 minute intervals, or could your power company or some local plant be sending something along the line periodically? Do you ever notice other telltale electrical artifacts, like lights dimming? I wonder whether powerline conditioning would help your situation.

I can't think of anything I have that powers automatically every 20 or so minutes...sometimes it's 20 minutes apart and sometimes if may occur twice in 10 minutes. It seems like I started noticing this shortly after I got my new sub...but I did not touch the cable going into the back of the reciever..BUT WAIT...when I had the sub installed, I happened to have an electrician at the house and I had him add an electrical outlet next to the pre-wired jack in the back corner of the room for the sub...THE SUB IS ON AUTO MODE....is it possible that the sub is turning on and off intermittently when it gets a signal from the reciever and the proximity of it's power supply to it's subwoofer cable in the wall is causing this?? The sub's amp is 1000watts....Is what I am describing possible!?!?

I'm not sure that I understand the various connections of your system, but my guess would be that the activation of the sub sends a surge through the system that somehow manifests on the plasma.

I have a pre-wired subwoofer line going from the receiver to the subwoofer (located in back corner of room with components in the front of the room). The subwoofer power supply outlet is right next to the pre-wired signal cable for the subwoofer. If the subwoofer is causing this problem, is there anything I can do to alleviate it? I have already sent SVS the scenario to see if they have any ideas......right now, the sub is plugged in without a surge protector (which I need to do), but I doubt this will help any with my current problem...

MCF,

I have a sprained hand that's making typing hard, so I have to be brief. It seems to me that you'll have to isolate the sub from the plasma's circuit somehow so that it doesn't make waves on it, if that's what's happening. One way would be to run a dedicated electrical line from the sub to your electrical box--a pain. Another would be to try a power line conditioner--not just a surge protector but something that also evens out the current and isolates ground--on the front wall components. You want to correct the problem as inexpensively as possible. If a cheap ground loop fix from Radio Shack works, great, but I'm not sure that it will. Pester SVS about it until they respond, and then maybe start checking out conditioners. I hope that the problem turns out to be simple.

Ed

the sub plugs into the wall using only TWO prongs, not three...therefore; how could it be a ground loop problem?? I thought you had to have a ground plug in order to have a ground loop problem.....any thoughts? Hope your hand feels better...