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Old 22-09-2011, 12:24
spiney2
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My Vestel T825 (alba) has been stuttering the past year, the problem moving around between different muxes, unpredictably.

Finally stopped, suddenly, after DSO on Sutton Coldfield.

As I previously mentioned on Futuara's website, the problem is caused by unknown extra data in the mpeg info fields, causing far more disc access than the power supply can handle (depending on which combo of hard disk/power board on a particular model).

This problem - peculiar to earlier Vestels - seems associated with DSO. I suppose we'll never know why it existed, ie what the extra info was ........
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Old 22-09-2011, 22:37
creddish
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My Vestel T825 (alba) has been stuttering the past year, the problem moving around between different muxes, unpredictably.

Finally stopped, suddenly, after DSO on Sutton Coldfield.

As I previously mentioned on Futuara's website, the problem is caused by unknown extra data in the mpeg info fields, causing far more disc access than the power supply can handle (depending on which combo of hard disk/power board on a particular model).

This problem - peculiar to earlier Vestels - seems associated with DSO. I suppose we'll never know why it existed, ie what the extra info was ........
Or it could simply be that as a result of DSO the transmitter power has been increased. I don't recall any other posters who have related stuttering to DSO.

Colin
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Old 23-09-2011, 00:50
futaura
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the problem is caused by unknown extra data in the mpeg info fields, causing far more disc access than the power supply can handle (depending on which combo of hard disk/power board on a particular model).

This problem - peculiar to earlier Vestels - seems associated with DSO. I suppose we'll never know why it existed, ie what the extra info was ........
I still don't understand how you apparently can state as fact that extra data in the mpeg info fields was causing the problem, yet you don't know why, what or where. If it were a problem, I would have thought the Vestel engineers would have seen this when they captured these dodgy streams when field testing in Manchester at a DS member's home prior to V12.8 and the V13.0 release (I guess you still don't believe this ever happened).

Until you can prove your theory, Colin's theory sounds far more logical to me. Could also be related to interference from neighbouring transmitters.
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Old 23-09-2011, 12:07
spiney2
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This problem - which 1st appeared during the WInter Hill DSO "period" - has absolutely nothing to do with mux power, as can easily be verified. It regularly swtiches around between muxes, whereas the mux powers remain the same.

(Just making such a claim implies basic ignorance!).

As I pointed out at length, on Futuara's blog, the problem relates to Vestel power supply defficiencies, As was well known,at the time, with various"fixes" already existing .......

I have no idea what Colin's theory is! Is it based on evidence, like mine ?
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Old 23-09-2011, 20:24
creddish
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This problem - which 1st appeared during the Winter Hill DSO "period"
This is certainly not true. The stuttering issue has existed on all the Vestel PVRs from the T810 onwards and was reported well before the Winter Hill DSO. Personally I have owned six Vestel PVRs so far and they have all exhibited this problem in varying degrees. My region does not have DSO until next year.
- has absolutely nothing to do with mux power, as can easily be verified. It regularly swtiches around between muxes, whereas the mux powers remain the same.
Stuttering is affected by MUX power, although it is not necessary for power to be low for it to occur. I have a very good signal level but have still experienced the problem. However a very low signal will cause the issue so if a user has the issue because of a poor signal then it is feasible that such a user could see the issue eliminated or much reduced following the increase in transmitter power at DSO.
(Just making such a claim implies basic ignorance!).
Hmmm.

As I pointed out at length, on Futuara's blog, the problem relates to Vestel power supply defficiencies, As was well known,at the time, with various"fixes" already existing .......
Can you give details of where this is posted on futauras site and who posted it? I would like to read it.

I have no idea what Colin's theory is! Is it based on evidence, like mine ?
You have not provided any evidence, just a claim which you, and only you, have said is fact. I did not claim my theory to be what happened in your case, just a plausible reason that a user who experienced stuttering before DSO could find it cured after DSO due to increased signal levels.

Colin
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Old 23-09-2011, 21:07
futaura
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Can you give details of where this is posted on futauras site and who posted it? I would like to read it.
I believe he is probably referring to http://pvrbugs.futaura.co.uk/view.php?id=167, which isn't really a blog - it isn't even supposed to be a discussion area, but it kinda turned that way for a little while .

Regarding Winter Hill, this was when the 8K mode with negative UHF offsets problem was first discovered with the T810 models, and remembering back to that point, this is what people were having problems with - not stuttering, which as Colin says, is not necessarily DSO specific.
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Old 24-09-2011, 18:53
spiney2
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Stuttering has nothing to do with mux power!

Please explain the physical mechanism involved, if U think otherwise.

The underlying problem is "not enough power oomph", with particualar hard disk brands, triggered by more than expected accesses .......

As was established, running the disk from an external PC power supply cures all such problems.

Anyone with the stuttering problem knows it only occurs when you begin recording, ie, when disk activity starts! The poorly regulated supply then crashes the controller ....

Most of the problems with winter hill were specifically stuttering.

I challenge anyone to either produce stuttering without the disk motor running, or with the disk removed !!!!!!!!!
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Old 24-09-2011, 19:02
spiney2
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..... for correct signal decoding, the Viterbi detector must be able to reconstruct the "most probable" bit sequence. If it can't you get nothing (the digital cliff). There's no way in which this can produce stuttering. What you'd actulaly get is pixilation, entirely different!
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Old 24-09-2011, 19:04
spiney2
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Futaura's website does a fine job of tracking PVR issues - which they all have - and obviously doing this requires work & money! Well done, sir. But, I believe this particular claim is factually wrong, along with the GEMSTAR patents one.
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Old 24-09-2011, 19:04
futaura
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Sorry, I got mixed up with Selkirk in my previous post! Indeed, Winter Hill was where the stuttering problems surfaced en masse, and this was obviously the transmitter that Vestel were concentrating on when field testing the software fixes themselves in Manchester.
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Old 24-09-2011, 19:06
spiney2
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What's puzzling is, y it didn;t noticably show up on previous DSOs. Must be something they started doing later on ........
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