dude, i'm the first one to admit that i know next to nothing about the science behind electronics and can't tell you for sure (obviously) what you're experiencing, but i would suggest trying one in your situation.
i've had shunyata, ps audio (passive), and audience conditioners in my systems, and the ps audio ones made the biggest improvement in video. i would try something like a ps audio quintet from a company with a return policy if you're not sure about it (if you shop around, you can find them "on sale" a few places...). quintets have a cable hook up as well, so if your signal is getting junk directly on the cable line maybe it could help it that way, too.
i have my cable box on a upc200 and my lcd tv on an ultimate outlet, and they cleaned up the picture noticeably and cured my banding issues (the conditioner on the cable box/dvd player seems to have a greater effect than on the tv itself, actually).
shielded cables to the tv, the dvd, the cable box, and the power conditioner help noticeably as well.
good luck, though, keep us posted of any results. |
Baffled,
Do you have a dimmer switch in your home? Either in a wall or on a light??? If so, try pulling them out of the circuit and see if that solves the problem, if you have a light with a dimer, just unplug it, if it's in the wall, you may get away with turning the light all the way on, or you might need to replace them with better dimmers, forget what they call them, but dimmers throw all kinds of noise into the power circuits.....
Just a thought, but I have seen this before and if it is your problem, it is easy to solve cheaply with eliminating dimmers or replacing them with better ones..... |
I'll vote for a cable induced issue. Most troublesome audio and frequently video anomolies are the result of the cable or satellite grounding.
Simply go out to the power pole where the cable or sat is grounded and lift (disconnect) it temporarily. Wait about 30 mins and look at the picture. it may taek a few more mins but in an hour or so you should know if that is the issue.
it's a simple enough task/test. If it is the issue there are isolation transformers that can solve the problem very cheaply.
True too you might not have a good enough ground. Sandy soil sheds water quickly too. Arid areas can be issues. I've heard from more than one source simply watering the ground rod area can remedy things.... which might account for the late night no prob thingy you have going on there.
If in an apt. simply remove the coax feeding the sat/cable box. Wait a while like i SAID ABOVE AND CHECK IT OUT.
Battery chargers too can cause problems in an audio or video rig if in close ckt proximity to the gear. timers too, like on hot water heaters, dishwashers, and or lighting.
If it is a ground loop, a power filter/conditioner usually isn't the fix.
you can also try using a decent sized ext cord and plug the TV into another ckt altogether.
Dew point raises at night, and your situation eases then, and why I say I feel it is a ground oriented issue. Unless you and your neighbor are using the same service I doubt the neighbor is the problem.
Good luck
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Thanks for the responses. There are no dimmers in use. Good suggestion though............I forgot all about that one. I did not even think to disconnect the sat. system. I assumed since there is distortion even when I am only using the DVD player, that eliminates the sat. TV. I suppose if it is a grounding problem it will be there as long as the sat. cables are connected. Since this is a weekend lake house, I will have to wait a few days to give that one a try.
The dry ground rod theory is interesting since the ground rods are under a covered deck. Hmmmm...that could even be a safety issue. Dang. Just dang. |
For not all that much you can get a Monster or APC unit designed for home theater with dedicated outlets offering component specific filtration. It makes a big difference and for a few hundred bux its less expensive then many alternatives.
FWIW I have always found that video displays benefit the most from power conditioning.
You could also try upgrading the cables from the sources to the display or the receiver and then to the dispaly - I doubt that it will fix the problem but it might make a nice small difference once you do... |
What happens with the raster when there's NO input connected at all? (this could be a way to trace the interfering source). If you have any GFI (Ground Fault Interrupt) distribution panel breakers or GFI outlets in the house, they too might be a problematic source of your RFI (radio frequency interference). Flourescent or halogen plasma lighting can even be an issue, but apparently not in your case At one point, the only breaker that was still on was the one for the TV. Regarding possible differences of ground potential on your incoming RF coax: you can try grounding the shield connector by stripping a few inches of small conductor (#22 awg or so) insulated wire & wrapping that around the F-connector shield, fastening it with a cable tie or tape wrapped around. Then connect the other bared end to an AC outlet cover mounting screw, which typically ties electrically to the AC outlet's ground. Or you can go right inside the outlet box & pick up the AC ground connection directly. I've had to use this shield grounding technique for video hum bar problems; others have used it successfully too. Your situation seems a little different, but this is simple & easy to try. You can also try completely isolating the coax by connecting two antenna matching baluns directly back to back (available at Radio Shack). The incoming coax connects into balun #1, then the 300 ohm twinleads tie directly to each of balun #2 twinleads. The 75 ohm isolated coaxial output is then taken out of balun #2. This is inexpensive & introduces some small signal losses, but if you have signal to spare then it's not a problem. There's a $100 coaxial isolation box available (from MIT?) that may or may not(?) introduce smaller RF losses. Sorry I don't remember those specs or the brand for sure. There could even be a source of external RFI getting into your equipment (nearby radio station transmitting tower or cell phone tower). Or a neighbor's CB radio or Amateur Radio transmissions. That might need to be shielded or trapped out. You can try a product from Audioquest called RF Stoppers. Basically they are split ferrite rings that come apart & snap together around your cabling (RF &/or power cables, etc). There are two levels: the Juniors & the Regulars, which are twice as thick & yield more RF filtering attenuation. Various diameters (I think?) are available. I saw a similar product at Radio Shack years ago; might still have them too. AC line conditioning is also worth trying of course. If the power cord is a detachable IEC type, some upgrade AC cords even have built-in filtering (such as JPS, MIT, or Custom Power Cord Co.) and many others. These cords have sometimes been reported to significantly improve video quality, even where interference is not an issue. Search the forum archives for specific posts in that regard. |
Thanks Bob! You lost me at "balun", but I understood most of your advice. I am going to start with removing the sat. box and DVD player altogether. If all is well, I will add back in the DVD and go from there. I am also going to check the neighborhood for Amateur Radio antennas. I am going to try watering the ground rods as well. (under cover of darkness, of course)
And then there is the nuclear power plant only five miles away....... |
Baffled
I don't know about the radio transmitter thingy... it would have to be real close given the FCC regs on output transmission power but not everyone plays by the rules in that arena.... it'll be easy to find out... simply look for the tower/antenna. it should be pretty big/tall.
Back in the 40s, my folks were in Biloxi Mx. at Keesler AFB. They had an apt. off base. My mom would play the radio on her fav station. Now and then she heard some other conversation coming over the radio ch a bit garbled and in a different language.
She told someone on base about it as she worked for the PX, and my Dad was in hte USAF. it turned out someone else in that same apt bldg was transmitting info about the base to another location... so she inadvertently helped capture a spy by paying attention to her radio.
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While you're looking over your grounding, check carefully for loose &/or corroded connections. Disassemble the clamp where the ground wire connects to the rod. Burnish the top of the grounding rod with a wire brush, emery cloth, fine sandpaper etc, exposing clean bright copper. Burnish the bare end of the ground wire too. Before reassembly, liberally apply some silicone paste such as SilGlyde (NAPA auto parts supply shop) or NoAlox paste (electrical supply shop or larger hardware store) or even automotive or marine bearing grease will work; this prevents the connection from re-oxidizing. Also check & clean the opposing end of the ground wire; whatever it connects to. Look for loose fasteners, apply paste, snug down the setscrew, etc. Check your house power ground also, if you can access that. Check the neutrals & ground conductors in your house power distribution box and all conductors at the load outlet for tightness & oxidation. You say ground rod(S), as in more than one? Multiple grounds could be a cause of ground loop noise, as per Jim above. This can also be a lightning electrical hazard due to differences in ground potential. You could try running all connections to a common ground post, or tie them together electrically with reasonable size conductors (#14 awg solid). isolating the coax by connecting two antenna matching baluns directly back to back (available at Radio Shack) A balun is a simple RF transformer. 300 ohm balanced twinlead connections at the (typically input) side (usually connected to a TV or FM antenna) and 75 ohm unbalanced coax connection at the other end (typically output) side; they will work in either direction though. You would need two as my previous post. Ask at Radio Shack. Also available at Lowes, Menards, Ace Hardware. If you don't understand RFI etc & want to learn more, then link to my Audiogon member email & leave me a phone contact. I am a federally licensed RF technician. |
You may also check for info on Audio Asylum. This is their tech dicussion section.
http://www.audioasylum.com/cgi/tv.mpl?forum=t2 |
Finally...............the solution! When my Oppo DVD player is connected to the TV with the DVI to HDMI connector, there is distortion whether the player is turned on or not. The problem is worse when the player is turned on. Using the component connection eliminates the problem. It took HOURS of trouble shooting to figure this out. Now, the question is why. I tried grounding the Oppo box and cable...........it made no difference. I see no difference in picture quality using either connection, so I am ok with leaving things as they are, but I can't help but wonder what went wrong. The set up was unchanged for about year and then suddenly the distortion appeared. Even when it is at it's worst, it comes and goes.
Thanks to all who have helped with suggestions. Without your help, I would have run out of things to check and given up.
Btw, while going through the breaker box I did find several loose connections. A worthwhile undertaking if you are qualified. |
congratulations on your perseverance John. This is hardly the first time that someone has resolved an issue without really understanding exactly what happened & why. I was thinking though, if you have further problems with the DVD player you could (1)replace it or (2)have it serviced (for possible degraded capacitor in the power supply) or (3)try an AC line isolation transformer, for power to that offending component only.
I had some screwball/intermittent noise problems with my computer, which I unsuccessfully tried everything that I could think of to fix. I ended up buying a small-ish (3 amp) isolation transformer on EBay for about $25. It was originally designed for homeuse medical equipment. What this does is float the power supply such that neither side of the AC line connects to household grounded neutral. Easy fix, but I don't know what / why either. |
This is Solder meister and I see that the Breaker Panel was mentioned.And yes many times when you have lose connections in a house this can cause the electrical system to interfere with audio and video equipment. I would recommend tightening your screws every say 3 yrs to avoid this. If you are comfortable and you are qualified to do this as getting across the wrong connections can be shocking. Also if you are building new or have access through a basement or open wall you can run separate electrical line to your home Theater system 15 amp should work fine I have personally one to the equipment rack one to the Sub and one to the Projector and house lights. It works wonderfully but not all have this option. Good Luck. |
I had a similar problem that manifested in my Acoustic Image electric Bass amplifier yet every thing else on that circuit seemed to work fine. Being a switching amplifier the low or lack of VAC caused the amp to completely shut down and reboot. Even with a digital multimeter running in the receptacle it showed no interruption.
Running an extension cord powered by another circuit to the amp proved successful which meant there was a problem somwhere in that circuit. I began by opening every receptacle box and removing the receptacle enough to examine them, working back to the breaker. A receptacle in the garage, where a work bench once stood, was charred and providing a minimal contact with the wiring. |
There's an answer for every electrical oriented issue. Most of the time it is found out for what it really is. sometimes it isn't.
usually it's one of three things... an opened ckt which equates to no power. A resistive connection which equates to an over draw of current to operate a thing, usually causing breeakers to trip routinely. or a ground somewhere on one leg or the other of a ckt.
A faulty wiring device can be any of or all of the above.
I think the ground loop issues, or seeming ground loop issues stem from the service itself. In some areas the neutral bus and ground bus at the service/meter are tied together.
Adaptive connectors which attempt to emmulate one they are not, like XLR>RCA, if not wired according to the way the maker of the item says, might well cause issues.
Reversing polarity along the way in a homes wiring can be problematic. Likewise, cables not terminated at either or both ends can be issues.
The fix often rests in going back to the last thing one has added or changed prior to the noticed descrepency.
Everything was fine until I plugged in the whosit to the whatzit.
...until I added cable.
.... got this new so & so... yada yada...
If it isn't obvious, like loose connections, burned receptacles, etc. just start at one end and go thru to the other. problems are normally at either end. Feed or supply. If not, ya just gotta check out the middle. visual inspections well reveal 90% of what the issue truly is.
DVI does not have as many conductors in it as HDMI does. The cable itself could be bad, or the source might not like being converted, Or the display/receiver might not dig it.
I use a DVI to HDMI adapter, and run HDMI CABLE instead of using a dual terminated cord.
it works great off the pc video card to the Onkyo rec. $5 from Dcables in TX.
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