Author Topic: Slightly noisy picture despite strong signal source and dark shadow  (Read 3951 times)

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chappers

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Has anyone got generic advice (although the LCD TV in question is a Samsung 710MP with MH17AS chassis) on why, despite a strong signal being present (analogue in this case from a Sky satellite receiver) of around 65-70dB, a set might display a very slightly noisy picture, akin to signal being slightly too low?

Another effect I have on this set, only on analogue RF, and NOT on SCART, etc., is that areas of dark shadow, such as the edge of a hand or face, are appearing as thick jet-black areas instead of graduated tones. With a face, it looks like a big paint brush has been used to paint a jet black thick line down the edge of the face. It is not affected by brightness, contrast changes, and is only apparent on RF input.

Thanks

Mulja tv repair portal


Keith

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Re: Slightly noisy picture despite strong signal source and dark shadow
« Reply #1 on: February 14, 2012,06:06:35 »
hi,

Probably an AGC problem.

The second problem sounds like a slightly of tune AFC tank coil.

Modern TV's don't have easy adjustment of these, but they may be adjustable in the service menu.

Keith

Mulja tv repair portal

Re: Slightly noisy picture despite strong signal source and dark shadow
« Reply #1 on: February 14, 2012,06:06:35 »

 

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