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Interference from lights on tv picture

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Old 11-02-2008, 8:50 PM   #1
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Interference from lights on tv picture

Any ideas would be appreciated.

Got my tv fed from a central cupboard in house containing sky/dvd player/video etc.It is a lexcom hub using lexcom cables.Next to this cupboard is my cupboard containing the c-bus dimmers etc for lighting.

There are a couple of horizontal lines on the screen which are continually scrolling.After closer inspection I realised that this is due to the lights in the tv room and adjacent room.The tv reception is fine when lights are off or fully on ....but when dimmed the problem appears.It also appears to be a local problem to the tv room rather than the central cupboards(tried dimming other light circuits -no impact on tv reception)So I am guessing soemthing is happening in the local light transformers causing this??Any ideas /solutions would be greatly appreciated.
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Old 11-02-2008, 8:52 PM   #2
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Re: Interference from lights on tv picture

Sorry omitted to say that this only happens with the sky picture....freeview is absolutely fine!
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Old 12-02-2008, 10:43 AM   #3
vex vex is offline
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Re: Interference from lights on tv picture

Are you watching Sky as a TV channel or as an AV / SCART based signal?

V.
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Old 12-02-2008, 8:40 PM   #4
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Re: Interference from lights on tv picture

From what I can see(unfortunately cant open the enclosure front at mom)
there are 3 leads coming from the back of sky box(as well as 2 sky cables)
1.tv scart connector from sky box to AV HOMEHUb distribribution system.
2.cable from Rf output at back of skybox to rf input on tv hub
3.finally another cable from aerial in at back of sky box to ....im guessing to aerial on roof
hope this answers ur question vex
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Old 24-02-2008, 4:00 PM   #5
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Re: Interference from lights on tv picture

any input would be hugely appreciated.

thks gavin
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Old 24-02-2008, 10:17 PM   #6
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Re: Interference from lights on tv picture

So on you tv do you tune to a tv channel to watch sky (channel 3 or 9 or something) or do you switch over to an AV input, called AV1, EXT1 or something like that?

V.
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Old 24-02-2008, 10:29 PM   #7
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Re: Interference from lights on tv picture

hi, im not sure what dimmers your actually using but if its low voltage lighting you will need low voltage dimmers, its the dimming of the transformer which does this, i had it on a lighting install i done recently, it was low voltage lighting on a standard dimmer which is fine for most current dimmers but these perticular transformers gave off intererence, changed to low voltage dimmers and all sorted, hope this helps


Dave
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Old 03-03-2008, 10:22 PM   #8
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Re: Interference from lights on tv picture

Sorry slow in replying.... been away on hols(it was jusy getting all to for me!!)

I watch Sky over the AV channel.
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Old 04-03-2008, 9:28 PM   #9
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Re: Interference from lights on tv picture

OK so is that the same with the DVD Player and Video ?

If it is only the Sky box, then I would try a different power socket to see if it is a bad earth on the socket. If not then it could also be an earthing fault on the sky box itself.

HTH

V.
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