Calling TV Experts

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mickthemaverick
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Calling TV Experts

Post by mickthemaverick »

I wondered if any of our resident TV engineers can tell me what might be causing the blue splashes effect in the following three TV screenshot pictures, from live and recorded sources:
Own work
Own work
Own work
Own work
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Own work

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xantia_v6
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Re: Calling TV Experts

Post by xantia_v6 »

What technology of TV is it? Are there any decoder boxes in the path?

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mickthemaverick
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Re: Calling TV Experts

Post by mickthemaverick »

Yes there is a Humax box fed by an aerial for freeview channels which is used for recording and playback of freeview. That is connected via HDMi to the TV and there is no coax connection to the TV. It is a 3 year old I believe LCD TV, it belongs to my friend in Elstree so I'm not fully conversant, I have just had an email saying that my advice of checking and wiggling the RF coax connections seems to have cured it!! I thought it might be a duff incoming signal so suggested a check of the coax before I posted my question, Thanks For looking, I'll come back if it re-occurs!! :)

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white exec
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Re: Calling TV Experts

Post by white exec »

There have been numerous reports of Sony, Samsung and other LCD tv's suffering blue patches (usually large soft ones) where the LED backlighting starts losing its correct colour-balance. My understanding is that 'white' LEDs are actually R-G-B devices, so maybe the R & G outputs begin to drop off. There is, apparently, no cost-effective repair for this, as it would involve the complete replacement of the LED panel behind the LCD screen.

In those photos, however, if the fault is present on all inputs, then it looks like the LCD screen itself could be at fault. The backlighting fault usually produces a soft area of incorrect colour.

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mickthemaverick
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Re: Calling TV Experts

Post by mickthemaverick »

Thanks for the info Chris, the screen was apparently fine using the PC connected to the VGA input so it does look like the issue was in the rf or maybe the Humax box but its been ok for the last hour since wiggling the coax plug in the wall. Maybe a duff socket connection which I'll look at on my next visit!! :)