Interference from terestrial

nickpmurphy

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Hi, I'm looking for help.

I have a standard Sky set up intalled about a year ago - Grundig digibox. Ever since it was installed there has been ghosting on Sky channels - faint images particularly of text (eg credits) which appear to be from whatever programme is on BBC1 at the time.

I've tried disconnecting the aerial from the digibox and just having it connected to the TV via SCART - this gets rid of the ghosting but gives an overall faint snowiness to the picture.

The signal strength bar shows about 70% and quality 25%. Is it a question of dish alignment?

Any help would be greatly appreciated
 

rolfw

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Unlikely that a poor quality measurement will cause the ghosting or snowiness, although 25% is lower than I would like and may cause picture breakup or pixellation.

It is more likely to be a dodgy or poor quality scart lead and or coax leads and connectors, the interference is probably coming from the RF input on the TV.

Are you using the RGB setting for your Sky output?
 

PaulR

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As Rolfw says the Scart lead is most likely ro be at fault. You need the type which has most of the inside leads individually screened - pull the cover off the scart plug to have a looksee.

PaulR
 

nickpmurphy

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Thanks for the prompt replies - yes the video output is RGB.

How do I tell from the SCART if the inside leads are screened?

Nick
 

rolfw

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With some you can pull off the cover and look, but if you have other leads as well, try swapping them around.
 

PaulR

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Also - if the combined scart cable lead (the outer sheath containing the individual leads) is relatively skinny then they won't be individually screened.

It's difficult to give precise thicknesses but if it's about the thickness of a pencil then it won't be individually screened, a thickness of about 10mm (3/8") will be individually screened.

PaulR
 

nickpmurphy

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Blimey - I've just swapped the digibox to VCR SCART cable (thick) with the one from digibox to TV (thin) and the interference has gone!!

I can't thank you enough - cheers fellas.

Nick
 
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