Hi I’ve got a HDTV - LED I think… often when the light switch (for a ceiling light) is turned off the sound immeditately goes silent for about half a second and the picture gets affected - it gets distorted. I’m using a fairly expensive surge protector. Does anyone know what the problem is? I’ve got a 5 year warranty but suspect that it isn’t enough to warrant returning it.
Determine if in fact the circuit is the offending problem. If need be use an extension cord and put the TV on a different circuit. Does the same thing still happen?. If so then I suspect RFI interference from surrounding appliances. Does your surge suppressor have a filter with it? If not I would go buy one that does. Monster makes several that should fit your application. Read the manual carefully, I think it mentions the possibility that other appliances can cause interference.
What sort of ceiling light do you have? Is it on a dimmer? When you are watching the TV what source are you watching? I assume it is broadcast TV.
As a rough guess the receiver in the TV is seeing a moment of RF noise that swamps the receiver, causing it to lose signal - it mutes the sound whilst it recovers, and the distortion of the picture is a result of the TV recovering the video stream. I assume you are watching digital TV, and the image shows the usual block artefacts.
I’ve known the same thing to happen, and been told it was down to the switch creating a spark which generates RF interference.
By distorted (a subjective term) should we assume you meant pixilated? Various squares have the wrong picture? Or does the picture simply tilt or look like a distorting Carnival mirror?
Why would a protector (that does nothing until 120 VAC exceeds 330 volt) - why would it do anything? Even an internal filter is near zero. Many know it has a filter, but forget to read its spec numbers. Typically near zero.
Now, how is that light switch creating an RF interference signal. Potential paths are numerous including through air and via many electrical connections from that switch even to the TV cable (or is it an antenna)?
Long before anyone can provide a useful answer, first define so many important and still not provided details. Francis Vaughan has only started asking for what must be first known. You did not even say whether it is receiving an analog or digital signal. Is that light on a circuit with the TV? And every question he also asked.
We know this. Your expensive protector is probably electrically equivalent to one selling in Wal-Mart for $8. Did you compare spec numbers? Did you read that 330 volt number on its box? Or just assume it is better due to a higher price and a fancier paint? Spec numbers are another important detail that must be provided before anyone can say anything but speculation.
Forget the surge suppressors & filters (and forget anything from Monster!) – spend 75¢ and 10 minutes work replacing that light switch with a modern one.
Seconded. A cheap and/or worn switch will not snap open and closed cleanly, and will generate a ton of noise and hash under the right conditions. New switch = problem solved, I’d bet.
Seconded on skipping anything branded Monster as well. The Bose/Dyson/Cadillac model of overpriced mediocrity.
The surge protector:
http://www.belkin.com/au/p/P-F9A402-2M
I’ve got the antenna cable going into and out of it.
The light switch is probably quite old. It happens with broadcast TV - I’m not sure if it happens with DVD’s.
There is some motion distortion… the colours are alright, the position of some picture elements are distorted.
I have no idea. I just thought it might be helpful to mention things like that.
Normally power sockets can be turned off separately to the light switches - or maybe I’m wrong - maybe they’re on the same “circuit”. It is a digital picture (MPEG2 probably) through an antenna cable.
No there is no dimmer. It flickers a lot when turning on so I think it is a fluoro light.
As far as I can remember it only happens on broadcast TV.
Often there is no picture distortion. When there is distortion it is quite minor - no unusual colours or excessive blockiness.
There is a potential problem. How strong is the antenna signal? Generally digital TVs can report that. If not a fully strong signal, then any noise will cause some “digital pixels” to not be receieved. And any one packet on audio means the sound must cut off until that digital stream is reestablished.
The Belkin will reduce that signal. Any noise on AC mains also will be connected to the antenna signal by that Belkin.
To protect the TV, other, superior, and much less expensive solutions exist. Meanwhile, remove the Belkin. It may not be the only incoming source of that noise. But it is definitely one. Noise on AC mains is connected to the antenna input.
You can check this at your main electrical panel. If the same circuit breaker shuts off both the light & the outlets in that room, they are on the same electrical circuit, and so electrical ‘noise’ from the light or switch can reach the TV. (All the electrical circuits come together at that main panel, but that is usually far enough away that the noise doesn’t travel back to the room & the TV strong enough to disturb ir.)
It’s possible that the continuous power wiring for the video gear goes through the light switch box and is being affected when the switch is jiggled. If you’re not a competent basic electrician, have one examine the wiring in the box while replacing the switch.
In houses of varying vintage, I’ve found everything from one box per connection, to massive amounts of wiring to reduce the number of boxes and fittings, to massive numbers of fittings to save wiring. (My current house, ca. 2002, uses a huge amount of wiring to allow 3 bathrooms on 2 floors to share one GFCI outlet’s protection. I rewired it with separate GFCI outlets, which is what would have been done a few years later when wire cost went through the roof.) So some ganged connections for both switched and unswitched power in one box are entirely to be expected and could be the cause.
When I stop the antenna cable from going through the Belkin device the problem goes away completely…
That is a pretty satisfactory answer.
I know you found a workable solution, but it actually sounds like the starter or ballast in the light fixture is failing.