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Old 27-12-2006, 19:19
aok
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I have a Sony DVD recorder with built-in Freeview tuner. My question is, what is the cause of the pixelation I get when either watching terrestrial channels through the Freeview box, or of a recording I have made of a TV programme. No problems with pre-recorded DVD's or while watching through analogue. I have had a new arial fitted with a booster prior to buying the recorder.
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Old 27-12-2006, 20:40
jer1956
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Originally Posted by aok
I have a Sony DVD recorder with built-in Freeview tuner. My question is, what is the cause of the pixelation I get when either watching terrestrial channels through the Freeview box, or of a recording I have made of a TV programme. No problems with pre-recorded DVD's or while watching through analogue. I have had a new arial fitted with a booster prior to buying the recorder.
Retail DVD's are going to have a bitrate of at least 7.5 mps. DVB-T rarely gets above 4.5 mps, and hence is crap most of the time. In my experience UK designers are well aware of the crap broadcasts and produce STB's which are heavily MPEG filtered to get a watchable output. PACE STB's are often crticised for producing "soft" images, probably a result of the MPEG filtering. Your Sony DVD Recorder dosn't have such filtering, and will produce a sharpe, and very blocky output. It problably works great in Japan!
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Old 28-12-2006, 12:45
aok
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Thanks for replying, but to be honest I don't understand what you are saying. Most of the time my picture is fine, but every once in a while I get pixelation, which sometimes will also distort the sound. This only lasts for a few seconds but can spoil the viewing. On average it probably occurs about once every 2 hours of viewing....not a lot I know but still infuriating. I didn't know if it was down to the reception or a fault with the freeviewer combined in my DVD recorder
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Old 28-12-2006, 12:51
Jarrak
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So you are not talking about an inherent issue with the overall picture quality of the Freeview channels but a sporadic breakup of the signal which can cause video and audio corruption?
If that is the case then it's probably some external interference which some receivers are better than others in handling. It may be in electrical system, boilers switching on for example or radio interence (dect phones, car alarms etc).
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Old 28-12-2006, 14:34
aok
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Yes, you have it, it is very sporadic. It doesn't seem associated with any other appliance switching or or off, do you think a better arial might improve it?
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Old 28-12-2006, 16:13
Jarrak
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Perhaps a question for the Freeview/Terrestrial forum

I took the easy route, had a brand new aerial installed and have pretty much perfect reception and no intereference on both my Freeview boxes, never really needed to delve deeper into the causes of picture problems.

It may be that the tuner in the DVD/Freeview box is a little more susceptible to interference than other tuners, early freeview and ondigital boxes could be affected by passing cars or fridge motors
Borrowing a friends Freeview box for the night could be worth while if only to test the quality of your signal on a new tuner.
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Old 28-12-2006, 18:04
jer1956
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Originally Posted by aok
Thanks for replying, but to be honest I don't understand what you are saying. Most of the time my picture is fine, but every once in a while I get pixelation, which sometimes will also distort the sound. This only lasts for a few seconds but can spoil the viewing. On average it probably occurs about once every 2 hours of viewing....not a lot I know but still infuriating. I didn't know if it was down to the reception or a fault with the freeviewer combined in my DVD recorder
Now you give us the full story!

Surpriseingly DVB recievers can get too strong a signal, which can cuase problems like you now describing. Fitters often have to fit attenuators if you live too close to DVB transmitters.

You should only amplify a DVB signal if a fitter recommends it.
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