I have a weird problem that comes and goes.

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highskies

SatelliteGuys Pro
Original poster
Feb 15, 2010
398
10
Texarkana
It rarely goes away once it comes. On all my display devices, my tvs, my front projector, etc, this occurs. I basically lose all black level in bright scenes, such as outside scenes. For example, there is no color in the sky, it's all white, like over saturated or something. When this happens, if there's trees in the shot, you can't make them out, they look over saturated as well. It completely destroys the black level. This only happens on C-Band and KU, both dvb and DCII. This also affects the colors in the pictures. The yellows don't look naturally yellow, but over saturated as well. I'm not even sure if that's the right term to describe it.

But if I put a dvd on, never a problem. The black levels always look accurate. So I'm starting to think that maybe something in one of my neighbor's houses is spiking the signal somehow, thus cause the pic to look bad. When this happens, no amount of adjusting
the brightness, contrast, does a thing to fix the problem. I'm to the point where I can't even stand to watch anything on satellite, not to mention, when this happens, it introduces ugly artifacts into the pic, such as zig zags or stairstepping..whatever it's called. I've tried both Svid and Composite..same problem with both. It even does it on my pc thru the 1030a card. Really noticeable when I run that pic thru the projector. IOW, no Svid or Composite cables in the loop. Just straight RG6 and the pc monitor cable.

I have neither of my dishes grounded. But I don't see what that would have to do with this. And before I forget..it's like this on all chs during bright scenes, or even scenes with a lot of white in them, such as someone with a white shirt, etc. You can't make out the details in the shirt, such as buttons, and the white doesn't even look naturally white..it just looks bright and unnatural. For the life of me I can't figure out what's causing this. This has been ongoing for a few years now. Anyone have any clues? What to check? I don't have any test equipment, so don't ask me to put any meters on anything. All I have is my eyes. And my eyes are telling me it aint worth watching most of the time.
 
bug chasiing

You have two receivers?
4Dtv and an FTA receiver?
Oh, and 1030a card in your PC, too. ;)

You have at least two TV sets?
A front projector and another set?

Okay, what is in common?
You running the video through a switcher or home entertainment system of some sort?
If ya want to sketch up a drawing of how it's all hooked up, maybe something will be obvious.


To review: multiple TV sets display this problem?
So, it's not likely a problem with a TV set.

Multiple satellite receivers display this problem?
So, it's not likely to be a problem with one of them.

I'd say it's whatever is left. ;)
 
You have two receivers?
4Dtv and an FTA receiver?
Oh, and 1030a card in your PC, too. ;)

You have at least two TV sets?
A front projector and another set?

Okay, what is in common?
You running the video through a switcher or home entertainment system of some sort?
If ya want to sketch up a drawing of how it's all hooked up, maybe something will be obvious.


To review: multiple TV sets display this problem?
So, it's not likely a problem with a TV set.

Multiple satellite receivers display this problem?
So, it's not likely to be a problem with one of them.

I'd say it's whatever is left. ;)



The only thing in common is that one tv, the 922, and the dvb receiver, these are all plugged into the same powerstrip source. No switchers or anything. Since I like to use my front projector at night, the problem is the most noticeable on there. But it has nothing to do with the front projector, because dvds look killer on it. Satellite also looks killer on it as well, whenever it's not displaying these symptoms. So that tells me that something is overdriving the video signal sometimes for some reason. If so, what? Something in my neighbor's home? It's perplexing to say the least.

Since it does it thru any cables I use, I would think that rules out the cables. Since it does it thru all my display devices, I would think that rules out any problems with a particular display device. Since it does it on both the C-Band dish and KU offset dish, I would think that rules those out. The only thing left that I can think of, something is overdriving the video signal somehow. But what? And like I pointed out, never a problem with dvds. Anyone that cares about PQ knows how important black levels are. They make the picture pop and come to life. It sucks when the black lebels are being ruined by the background somehow, like on outdoor shots.
 
This may not help, but I thought I would put the idea out... Your problem may not be overdriving, but may be 'overloading'. Either way, it may be caused by an intermittent cable in the system. Have you tried replacing the video signal cables in your system, one at a time? [You've probably done that...] I think it is not a problem related to power or any cause external to your system, so I think your neighbor's home is not a cause. I think that the fact that the DVD never has a problem, it a good clue to the elimination process. Whatever is in the system when DVD is used, is NOT the fault cause. Anything else should be reconsidered as a cause. A fault on the output of a receiver or on the input of a display device COULD be affecting anything that the cable connects to. Try to 're-think' your elimination process and see if you can find the problem. As Anole says,a diagram would definitely help in the troubleshooting, as it helps to defined the areas where we can suggest investigation for problem cause. I have had some problems that took months to eliminate, just don't give up! Good Luck!
 
This may not help, but I thought I would put the idea out... Your problem may not be overdriving, but may be 'overloading'. Either way, it may be caused by an intermittent cable in the system.


Actually it does help since what you say seems logical, The more I think about it, overloading seems to be a good description. Could you list some things that may cause overloading? I know you already mentioned the video cables. Is there anything on the dishes themselves that could be causing this? Then there's the receivers..it does it on both the 922 and dvb receiver. I would think that eliminates one of them as suspect, but not certain tho. Anything you can think of to add to your prev post, it will be greatly appreciated, because like I said early, it's to the point where I can't even stand to watch anything on satellite anymore. Dark scenes are not much of a problem tho. It's when the scenes are well lit or take place outside. Then it's basically unwatchable as far as I'm concerned.
 
Possibly a ground loop? Can you try wiring up a minimal system. i.e. Only connect the satellite receiver to the TV, and the dish (LNB) to the satellite receiver with any switches, motors, etc removed. Unplug all other cables plugged into the TV, Satellite receiver, and dish. If you have a second cable from the LNB to a second receiver, remove that cable also. Try to have nothing extra plugged into the LNB, Satellite receiver and TV then see if you still have a problem.
 
Possibly a ground loop? Can you try wiring up a minimal system. i.e. Only connect the satellite receiver to the TV, and the dish (LNB) to the satellite receiver with any switches, motors, etc removed. Unplug all other cables plugged into the TV, Satellite receiver, and dish. If you have a second cable from the LNB to a second receiver, remove that cable also. Try to have nothing extra plugged into the LNB, Satellite receiver and TV then see if you still have a problem.



I'm going to give your suggestions a try. But first, could you clarify a few things? I use the 922 to steer my C-Band dish. Since there's not much on the 4dtv anymore, I'll want to you my dvb receiver for the test. After I get the 922 to move the dish to the desired sat, so that I can test thru the dvb stb, I then unplug the 922 from the same powerstrip the dvb stb is hooked up to. The only thing I have plugged in now is the tv and dvb stb. The only thing I have going into the dvb stb would be the lnbf rg6 cable. The only thing going out of the dvb stb would be the video cable going into the display device. Would this be correct so far? Even tho the 922 is unplugged, what about the motor wires going into it? Do I need to remove these from the 922 as well? For the sake of argument, let's say this fixed the problem? How would I know exactly which of these things was causing the ground loop? Then OTOH..nothing is resolved. Does this mean it wasn't a ground loop? Or would there be something else to check in order to determine if there is still a ground loop?

Speaking of grounds..like I already mentioned..neither of my dishes are grounded. Could this have anything to do with anything?
 
Speaking of grounds..like I already mentioned..neither of my dishes are grounded. Could this have anything to do with anything?

As long as you've grounded by using a grounding block which is tied back to your breaker box ground you should be find, that's the only way I have mind setup.
 
As long as you've grounded by using a grounding block which is tied back to your breaker box ground you should be find, that's the only way I have mind setup.



I haven't even done that. Neither dish is grounded in any way. I don't think I've ever grounded any of my dishes. Could something like that be producing some of these symptoms I've been describing?
 
With multiple pieces of equipement plugged in, grounds for each piece can be at different voltages. Then each piece of equipement is connected together by their various cables. This can cause a current to flow from the ground of one piece of equipement to another. This can be through a video cable, audio cable or anything that connects the gounds together. By removing the cables from each piece of equipement, you can eliminate the possibility of that piece causing the problem. Most commonly with video euipement, if there is a ground problem, you will see rolling bars in the video.
 
I haven't even done that. Neither dish is grounded in any way. I don't think I've ever grounded any of my dishes. Could something like that be producing some of these symptoms I've been describing?

It could, but not being there and seeing what's happening it's nearly impossible to be sure about what's causing your problem. The first thing would be to install the grounding block. I'm guessing that this issue just came up and that nothing new has been added, so when this starts happening try unplugging your OTA and satellite cables or any other outside input and see if it changes. You first need to figure out if it from and outside source or inside and is it time related. Once you that's determined it should be easier to fix.
Lot's of thing could cause this problem, a bad outside transformer shorting out, a neighbor welding, inside lights or even a amateur ham operator so the list could be long.

After a little hunting I finally found this old FCC link that was saved by another person that I had saved some time ago, it may just help you trouble shoot your problem.

http://www.kyes.com/antenna/interference/tvibook.html

Also to help you might go to Google then under Images put in TV Interference and see if any of the pictures look like your problem.
 
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It rarely goes away once it comes. On all my display devices, my tvs, my front projector, etc, this occurs. I basically lose all black level in bright scenes, such as outside scenes. For example, there is no color in the sky, it's all white, like over saturated or something. When this happens, if there's trees in the shot, you can't make them out, they look over saturated as well. It completely destroys the black level. This only happens on C-Band and KU, both dvb and DCII. This also affects the colors in the pictures. The yellows don't look naturally yellow, but over saturated as well. I'm not even sure if that's the right term to describe it.

But if I put a dvd on, never a problem. The black levels always look accurate. So I'm starting to think that maybe something in one of my neighbor's houses is spiking the signal somehow, thus cause the pic to look bad. When this happens, no amount of adjusting
the brightness, contrast, does a thing to fix the problem. I'm to the point where I can't even stand to watch anything on satellite, not to mention, when this happens, it introduces ugly artifacts into the pic, such as zig zags or stairstepping..whatever it's called. I've tried both Svid and Composite..same problem with both. It even does it on my pc thru the 1030a card. Really noticeable when I run that pic thru the projector. IOW, no Svid or Composite cables in the loop. Just straight RG6 and the pc monitor cable.

I have neither of my dishes grounded. But I don't see what that would have to do with this. And before I forget..it's like this on all chs during bright scenes, or even scenes with a lot of white in them, such as someone with a white shirt, etc. You can't make out the details in the shirt, such as buttons, and the white doesn't even look naturally white..it just looks bright and unnatural. For the life of me I can't figure out what's causing this. This has been ongoing for a few years now. Anyone have any clues? What to check? I don't have any test equipment, so don't ask me to put any meters on anything. All I have is my eyes. And my eyes are telling me it aint worth watching most of the time.

Are you using any modulator, like a Channel Plus, to extend the "channel" you are seeing the problem on? In my experience, this is "overdrive"; caused by a breakdown in a modulator, or the links to one, which is in a output of a channel being modulated. Since it is in both receivers?; are you combining it or looping it through something anywhere to make them both play on the same rg-6?
 
I like Larry1's suggestion. If you are seeing the problem on the 922, connect the 922 directly to your TV [projector or other...], and have no other connections to either the TV or the 922 on the OUTPUT side of 922 or on any input to the TV. Don't worry about what is plugged in to the power strip. Have it set up so that you have Dish - cables to 922 - cable to TV and nothing else is connected to either dish, 922 & TV. If you have the problem with this setup, then all the disconnected devices are 'innocent'. I am thinking that you have a defect in a cable or a unit that is affecting the video signal. I have 3 dishes, 2 OTA antennas with amplifiers, 3 receivers, 2 modulators, and several TV's fed throughout the house and I made NO SPECIAL GROUNDING connections anywhere and have never had a ground loop problem. Good Luck!
 
One thing is for sure; this type of problem is very prevalent as a "problem" in video distribution. Recently, well, in the past 20 years, I have removed such problems in video systems many times. More often than not; the cable company has changed a "procession" of their system, channels added, internet added, their ground status either removed or changed; just depending on the new equipment they put at their co, and throughout their distributions of their services and types of distributions. When the cable company removed true grounding, they put a voltage or carrier, on the external foils of an rg-6 coax (the internet). This absolutely ruined modulators of old, and any combining that modulated systems used in the past. Plus, as they put up more and more clients, their voltages went higher. Do you have the cable company in your "system"? Modulators, and those parts before the modulators (caps, resistors, diodes, amp circuits) also wear out in time; that is, the inside of a receiver; and this will show up as the hummer bars you have described.. Have you tried another device to supply video to your "system"?
 
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