TV flicker with light switches

[Gingerbread Man]

Interesting topic. I'm in Oz. And have the same issue.

Panasonic LED TV, Denon Amp, Logitech Harmony One (not sure if relevant but you mentioned the same).

Today I was watching a film via a windows 7 based media centre, using the TV and the Amp. My girlfriend is making a dress today and has been plugging the iron into the same power board behind the TV. When she does this the TV screen goes blank for a second as if you'd changed input. The TV displays HDMI 1 (was in use) like it just found the feed and then all is fine to watch again. 2 second interruption maybe?

The same thing can occur using the ceiling lights in the house. In the laundry (off the lounge) the TV input will display and pause for a tick.

I can't recall if it happens when watching normal TV (Amp only processing sound, no picture) of only when a feed is passed through the Amp.

The TV's Australian, the Amp and media centre are from the UK where all was fine.


Just thought I'd tune in to share the Misery!

[AW10]

OP, have you confirmed that all of the outlets you're using are actually earthed? I recall a mate's flat on the continent where he cracked the outlet and went to replace it before he moved out. Bought a new outlet, swapped it only to find there was no earth wire at all - someone had installed an earthed outlet, probably so that they could use an earthed appliance. Not clever but it happens.

Gingerbreadman - sounds like voltage drop? An iron should be a pretty benign item to switch on and off. Presumably the telly blinks every time the iron starts a reheat? Just in case can you try a different iron?

[beanbag]

AW10 said:

OP, have you confirmed that all of the outlets you're using are actually earthed? I recall a mate's flat on the continent where he cracked the outlet and went to replace it before he moved out. Bought a new outlet, swapped it only to find there was no earth wire at all - someone had installed an earthed outlet, probably so that they could use an earthed appliance. Not clever but it happens.

Gingerbreadman - sounds like voltage drop? An iron should be a pretty benign item to switch on and off. Presumably the telly blinks every time the iron starts a reheat? Just in case can you try a different iron?

I'm pretty certain it's earthed. I checked with my multimeter and got a complete circuit.

I'm expecting delivery of my filters today so I'll attach these to all the HDMI leads and power chords. I'm hoping this will work, otherwise I'll probably invest in a decent APC back up power supply to try and filter out the voltage drop and noise.

[westom]

beanbag said:

I'm pretty certain it's earthed.

Earthing is clearly irrelevant. Provided was how to identify a fault circuit long before fixing it. Noise from a switch has no relationship to earth ground - or safety ground for that matter. You do not even know if the noise is entering on AC wire or coax cable. Or is using a circuit that involves both.

BTW, meter can only check for conductivity of a safety ground - not earth ground.

[Gingerbread Man]

AW10 said:

OP, Gingerbreadman - sounds like voltage drop? An iron should be a pretty benign item to switch on and off. Presumably the telly blinks every time the iron starts a reheat? Just in case can you try a different iron?

Typically it's triggered by the lights. I just noticed the iron when she used it in front of me.

[beanbag]

An update on my part. I've put graphite noise filters on every sodding cable (including mains), without any success. It's definitely better but it's still flickering when I hit the light switch.

My missus is getting quite pissed off with it all as she thinks the amp is broken but seeing as it only happens when I turn something on and off, I think it's very much circuit related.

So what are my next options?

Should I return the voltage regulator?

What should I replace it with?

What can I test next before calling in an electrician?

[Gingerbread Man]

If you stick a multimeter in the socket and then turn the light on,would it register a spike? I thought being on a different circuit would seperare it all.

Or HDMI cable related. Not shielded, getting interface? I know that you can often change the TV input via signals from DVD player, etc.

Grasping. At. Straws. Mine never happened in the good old U of K.

[westom]

beanbag said:

What can I test next before calling in an electrician?

You are testing to fix it. Therefore you are only confusing yourself. And shorting your best help of any facts that can create a reply.

Posted previously was how to fix it. That means first defining the problem. You do not even know if the noise is entering on AC mains, coax cable, or via the air. Because you did not do what was recommended - to identify the problem long before trying to fix it (ie with filters).

BTW, if filters were a solution, those filters must typical weight on the order of 10 Kg. But again, any recommendation for a solution at this point can only be wild speculation. Already posted was how to obtain informed and useful replies.

[beanbag]

westom said:

beanbag said:

What can I test next before calling in an electrician?

You are testing to fix it. Therefore you are only confusing yourself. And shorting your best help of any facts that can create a reply.

Posted previously was how to fix it. That means first defining the problem. You do not even know if the noise is entering on AC mains, coax cable, or via the air. Because you did not do what was recommended - to identify the problem long before trying to fix it (ie with filters).

BTW, if filters were a solution, those filters must typical weight on the order of 10 Kg. But again, any recommendation for a solution at this point can only be wild speculation. Already posted was how to obtain informed and useful replies.

I get you're trying to help but this is all new to me. I'm no electrician so how about a little patience?

I don't have an APC unit to read the voltages as described. That would involve me having to buy one which I'd rather not do at this stage.

I've been trying to get through this in a logical manner and while I appreciate all the help, it might not be as clear to me as it is to (I presume), an expert like you.

So....as before. What is my next step? Clearly the filters were next to useless.

Do I return the APC voltage regulator and then what?

Do I buy an APC power supply and try and connect it to my laptop and monitor the voltages? It's quite an expensive option and I'd rather not do this unless it's very certain this will resolve the issue.

[Watchman]

I'm afraid I agree with westom. You need to isolate where the problem is before buying any resolutions like those filters (which, I guess are designed for line-level signals).

You keep mentioning the amp. Disconnect it completely. Does the TV *alone* exhibit the same behaviour with the amp taken out of the loop?

Can you borrow an inverter to power the TV? If mot, they are typically about 20 quid for one powerful enough to run an LCD TV. You may have spent more on stuff that doesn't help you already. Can you get your car close enough to connect the TV up to an inverter to see if the problem presents when the TV is run from an alternative source of power?

Next, do the same test with the amp in isolation.

You have to see if your equipment behaves the same or if one of the items behaves differently. You need to determine where the induced EMF is getting into the equipment - mains cabling or radiated EM interference. Once you know, you can look at possible solutions.

[westom]

beanbag said:

I get you're trying to help but this is all new to me.

When something is new, it is often not understood until a third reading. Among recommended actions was using a longwave (AM) radio. Were cable and AC electric properly earthed where both enter the building?

Strategy was defined in that first post. No good solution can be recommended without first defining how a noise (created by that switch) is getting into the TV.

A UPS costs maybe $50. Or could be borrowed from a friend. It is a temporary testing tool. If one cannot be obtained, then we move on to other means. But only if all first suggestions have been attempted. None required anything more than layman knowledge.

Maybe move on to shotgunning. That switch may have changed (as described previously). A switch is cheap and should not be creating noise. Replace it. But not until after collecting some facts (ie use the radio) to know what exists before any change is made. Since that change may provide more useful facts even if it does not fix anything. Only if symptoms are first collected before and after that change.

[JimbobVFR]

I had a similar problem that I traced to a failing power supply for 12V light fittings. I wonder if 1 or more of your led bulbs are failing, maybe remove the LEDs and add them back one by one might help find which one it is.

[beanbag]

JimbobVFR said:

I had a similar problem that I traced to a failing power supply for 12V light fittings. I wonder if 1 or more of your led bulbs are failing, maybe remove the LEDs and add them back one by one might help find which one it is.

I thought that too but they're 230v LED's so there's no transformer in the system.

I've decided to get an electrician in to check everything is working correctly while we're away on holiday. In fact, we're having the whole house re-done before we put it on the market so on another note, if you fancy buying a 3 bed home in the middle of a golf course near Marbella, let me know!

[AW10]

Surely the LEDs have drivers somewhere - the actual light emitting diode does not run off of 230V.

[JimbobVFR]

Yes there's some circuitry in the lamp itself. To make things worse it's all packed into a GU10 sized package and often doesn't have sufficient heat sinks.

I'll stand by my suggestion.

[Rodders1965]

beanbag said:

anyone?

I had problem with lights affecting my new 75inch tv tried surge protection didn't work changed HDMI for my Xbox one HDMI cable works perfect now