John if your new TV is HD or UHD or even HD ready, you should use HDMI leads. It makes no sense to spend dosh on a good TV then use cheap input leads that will not support the system to it's best advantage. What are you running the set on ? Sky box? or similar? HDMI leads are not the cheapest but Amazon will supply you with them at the best rates. I am surprised that the set did not come with at least I HDMI lead, or perhaps have a HDMI lead tucked away from when you had your digital box installed. If you are forced to go scart to HDMI perhaps this helps.
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