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The most useful thing you can do is lodge a written complaint directly to the station.They have to answer your complaint by law.It's not your tv's fault it is the station.You can upscale a dvd or download a show off the internet that will look great on your tv.So the real question should be not be how can i get my tv to mask the third world cr@p but why are we getting the third world cr@p in the first place.

something useful would help.
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Not sure about the “V” series but most Panasonics employ filtering on SD source which unnecessarily softens the picture, there is not way to turn the filtering off either.

A work around is to use an external set top box, PVR etc that up scales, when the TV receives a HD signal it will not enable the filter.

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Buzz is due to vibration, find the part that is vibrating, apply damping to that part to reduce or eliminate the vibration and the noise/buzz will be diminished or eliminated, its not rocket science.

Vibration is due to the EMF created by high AC currents so any component that carried such currents is suspect. The prime candidates are the power supply board, panel driver board and the Plasma panel its self.

http://www.americanpiezo.com/piezo_theory/index.html

I'm told something like this is likely to be my chip buzz issue, not simply EMF. Try stopping atoms from vibrating without breaking the device Owen - I dare you. It's not rocket science indeed.

;)

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So “chips” have piezo electric devices in them do they????

Show me a TV schematic that shows a piezo device.

“Chips” contain semiconductors and they are not piezo electric.

Run some audio frequencies through a high power amp at full output and tell me how much noise is emitted by the amp electronics. Hope your ears are good. ;)

Piezo devices have to vibrate to make noise, damp that mechanical vibration and you will suppress the noise, same goes for any electronic or electric device, it's not rocket science.

Edited by Owen
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So “chips” have piezo electric devices in them do they????

Show me a TV schematic that shows a piezo device.

“Chips” contain semiconductors and they are not piezo electric.

Run some audio frequencies through a high power amp at full output and tell me how much noise is emitted by the amp electronics. Hope your ears are good. ;)

Piezo devices have to vibrate to make noise, damp that mechanical vibration and you will suppress the noise, same goes for any electronic or electric device, it's not rocket science.

I never said it was a piezo device, but rather a piezo effect.

I refer you to my original post that points out I'm simply talking about possible things that buzz in electronics, not necessarily tvs (which is why I said you're mostly correct, but may not totally be.)

http://www.dtvforum.info/index.php?showtop...t&p=1592534

I also refer you to this wiki page that says your definition of what's possibly in a chip is elementary at best.

http://en.wikipedia.org/wiki/System-on-a-chip

;)

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Hi All,

I had my buzzing 54v20 replaced after a couple of weeks as it was not "normal" as far as i was concerned. I am happy to say that the new replacement 54v20 works as exepected with absolutely no buzz at all. My folks have a hitachi thats getting on now and there is no buzz and never has been from that tv. I don't know why this model is subject to buzzing and it seems quite prevalent but i would not accept and be seeking replacement from your retailers.

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A “chip” is a semiconductor substrate with lead out wires embedded in a block of epoxy, it is a solid with no internal parts free to move or vibrate independently of the epoxy casing. If the internals of a “chip” where permitted to vibrate independently of the case and lead wiring the device would fail very quickly as the lead wires would fracture. The “chip” vibrates as a whole and that vibration is transmitted into the circuit board which in turn vibrates greatly amplifying the noise.

I'm no expert, I know I've said that a few times now but I'm really stretching to see how it all works now... This statement bugs me, I know the chip makes a buzz and no one disputes that (yet!) - if it were EMF making it do so it would need one of the two things interacting to be applied from outside the chip if it were not free to move from within. But there's no magnet or any sort of metal outside the chip (in my case) that would allow the entire framework of the chip vibrate in the same direction. The only way I can see it making a noise is for something within it to be "bulging" at some frequency, making the two main surfaces of the chip the things that are being "pushed".

As I imagine myself trapped in a box full of sand, how do I not move but yet manage to get the box to jump even slightly?

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Are you referring to the “chip” you fitted a P4 heat sink to?

What is the function of that “chip” and what sort of equipment is it used in?

Did touching the “chip” with your fingers reduce the noise?

I have worked on electronics both analogue and digital for 35 years and never found a “chip” that buzzed or made any significant sound what so ever, however coils and transformers regularly make a noise and in high power applications noise from such passive components is almost unavoidable.

The switch mode power supplies used in most PC’s and most TV’s these days do “buzz” and sometimes sing but it’s not the semiconductor components (chips) making the noise.

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Are you referring to the “chip” you fitted a P4 heat sink to?

What is the function of that “chip” and what sort of equipment is it used in?

Did touching the “chip” with your fingers reduce the noise?

I have worked on electronics both analogue and digital for 35 years and never found a “chip” that buzzed or made any significant sound what so ever, however coils and transformers regularly make a noise and in high power applications noise from such passive components is almost unavoidable.

The switch mode power supplies used in most PC’s and most TV’s these days do “buzz” and sometimes sing but it’s not the semiconductor components (chips) making the noise.

I love this. In relation to what chip and its function, you clearly didn't read or understand my posts. Go back and do so, and don't waste my time. Who cares anyway - it's clear you have little idea of what they've been doing in the past 10 years IN ALL AREAS with electronics. Your comments and jibes (at me and others) in previous posts indicate that. But I see you're keen to move on past that now without saying another word about it. Your previous comments have been wrong, be a man and admit it before moving on.

If I put my finger on the chip and the sound was reduced, it would be because I was insulating the surface from the air - not because it vibrated less. I wouldn't be able to keep that up anyway because it was too hot, and is one of the reasons I think it couldn't be fixed... Can't be fixed = impossible, impossible = harder than rocket science. It's not rocket science, Owen.

Yeah, yeah, worked in this field or that - oh, you must know everthing about everything then. Wake up to yourself man. That attitude is what's stopping you from learning anything new and coupled with jibes makes you a tool. Saying it's not chips in switch power supplies in tvs making the noise is pointless, you're avoiding other boards that contain SoC devices and leading readers to believe it can't happen in tvs.

These sort of chips (SoC) are being used more and more in everyday electronic toys, phones, tvs and the like. Probably not many of them make a noise, some do, there's been a few I can think of - like chips in tv tuners too when they adjust the frequency they listen in on... But if you say none make a noise, so be it, once again you know best.

Now buzz off.

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in high power applications noise from such passive components is almost unavoidable.

Almost missed this golden opportunity: so, it is starting to become as hard as rocket science?

Buzzzzzz

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I love this. In relation to what chip and its function, you clearly didn't read or understand my posts. Go back and do so, and don't waste my time. Who cares anyway - it's clear you have little idea of what they've been doing in the past 10 years IN ALL AREAS with electronics. Your comments and jibes (at me and others) in previous posts indicate that. But I see you're keen to move on past that now without saying another word about it. Your previous comments have been wrong, be a man and admit it before moving on.

If I put my finger on the chip and the sound was reduced, it would be because I was insulating the surface from the air - not because it vibrated less. I wouldn't be able to keep that up anyway because it was too hot, and is one of the reasons I think it couldn't be fixed... Can't be fixed = impossible, impossible = harder than rocket science. It's not rocket science, Owen.

Yeah, yeah, worked in this field or that - oh, you must know everthing about everything then. Wake up to yourself man. That attitude is what's stopping you from learning anything new and coupled with jibes makes you a tool. Saying it's not chips in switch power supplies in tvs making the noise is pointless, you're avoiding other boards that contain SoC devices and leading readers to believe it can't happen in tvs.

These sort of chips (SoC) are being used more and more in everyday electronic toys, phones, tvs and the like. Probably not many of them make a noise, some do, there's been a few I can think of - like chips in tv tuners too when they adjust the frequency they listen in on... But if you say none make a noise, so be it, once again you know best.

Now buzz off.

Ok, so its a network hub and the large chip is likely the processor, the internals of which are running in the gigahertz region(1,000,000,000Hz), thousands of times above the range of human hearing. Maybe you have some explanation how it could generate a sound that could be classified as a “buzz” which is typically in the 50Hz to 100Hz range when it contains nothing running at even close to that sort of frequency.

I don't doubt the hub makes a “buzz” however I do question your diagnosis of the source.

The power supply components see the 50Hz mains frequency and 100Hz ripple, don't you think they are more likely the source of “buzz”?

Back to the topic of Plasma “buzz”, are you suggesting that the source of “buzz” on Plasma TV's is a chip?

Buy the way, firmly attaching a heat sink with significant mass with dramatically change the resonant frequency of the “chip” in much the same way as putting your finger on it. Bingo a reduction in noise, not rocket science. :rolleyes:

As for those SoC “chips”, how many of then run at a frequency even close to the range of human hearing (20Hz to 20,000Hz)? TV tuners are receiving frequencies around 100,000,000Hz, thats bound to "buzz". :lol:

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Ok, so its a network hub and the large chip is likely the processor, the internals of which are running in the gigahertz region, thousands of times above the range of human hearing. Maybe you have some explanation how it could generate a sound that could be classified as a “buzz” which is typically in the 50-100Hz range when it contains nothing running at even close to that sort of frequency.

I don't doubt the hub makes a “buzz” however I do question your diagnosis of the source.

The power supply components see the 50Hz mains frequency and 100Hz ripple, don't you think they are more likely the source of “buzz”?

Back to the topic of Plasma “buzz”, are you suggesting that the source of “buzz” on Plasma TV's is a chip?

Until you tell me where you've gone wrong in your posts here, there's no point me trying to work out what you're thinking and where I have maybe made a mistake myself, or try to continue the discussion given you have thrown out the facts I've presented and left me nowhere to go... But that's our choice to ignore... I just find it rude, and won't continue much longer.

How do you know what's in the chip and that it doesn't generate a buzz in the 100~18000 range (I never specified what frequency is was after all - and yes, it would seem much higher than 100 by a guess.)

As for plasma buzz, no, I don't think it is, I never said it was - I also said I've not heard this chip buzz as loud as a plasma buzz... It was just a comment of what's possible and if you happened to get a really bad design or a bad chip in manufacturing that worked but was more noisy than I've heard, then you might not be able to do what you suggest. You might need something more or different or not be able to fix it at all. It was always your choice to agree at the time, or at least say insulation is another option regardless of what's really happening, but instead you haven't and have continued to try and disprove there was anything in what I was saying. I do find it funny though that you are looking to disprove my statements now by suggesting it's not something I never said it was.

But now you have been shown to have a limited understanding of things you claim expertise in, that worries me - because you're obviously willing to argue using bad information to make your point or support some advice you've given people before when you may not really know the full consequences.

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Buy the way, firmly attaching a heat sink with significant mass with dramatically change the resonant frequency of the “chip” in much the same way as putting your finger on it. Bingo a reduction in noise, not rocket science. :rolleyes:

As for those SoC “chips”, how many of then run at a frequency even close to the range of human hearing (20Hz to 20,000Hz)? TV tuners are receiving frequencies around 100,000,000Hz, thats bound to "buzz". :lol:

:)

Funny. And yet the buzz will still come out the underside of the chip - with it never have been eliminated.

As for running frequencies, is it really true that everything runs at those frequencies, just because the main function does? Is that really what your saying now? I just want to make sure.

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Sorry I'll correct my punctuation.

If the “buzz” was coming from the speakers, filter capacitors in the power supply could be the cause.

If the “buzz” is not coming from the speakers there is NO WAY its due to faulty capacitors.

I am an electronics tech.

For example: (think faulty as the wrong value maybe?)

http://www.at91.com/forum/viewtopic.php/f,15/t,921/

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Until you tell me where you've gone wrong in your posts here, there's no point me trying to work out what you're thinking and where I have maybe made a mistake myself, or try to continue the discussion given you have thrown out the facts I've presented and left me nowhere to go... But that's our choice to ignore... I just find it rude, and won't continue much longer.

You will have to spell it out mate, to use an old term, I'm not catching your drift. :huh:

How do you know what's in the chip and that it doesn't generate a buzz in the 100~18000 range (I never specified what frequency is was after all - and yes, it would seem much higher than 100 by a guess.)

Once you get to more than a few hundred Hz the sound will be a tone not a buzz (voice frequencies are in the low hundred hertz region), go higher again and you get what most would describe as a whistle.

As for plasma buzz, no, I don't think it is, I never said it was - I also said I've not heard this chip buzz as loud as a plasma buzz... It was just a comment of what's possible and if you happened to get a really bad design or a bad chip in manufacturing that worked but was more noisy than I've heard, then you might not be able to do what you suggest. You might need something more or different or not be able to fix it at all. It was always your choice to agree at the time, or at least say insulation is another option regardless of what's really happening, but instead you haven't and have continued to try and disprove there was anything in what I was saying. I do find it funny though that you are looking to disprove my statements now by suggesting it's not something I never said it was.

Look mate, I am not being argumentative for the hell of it, I really have been working on electronics for 35 years and cant remember ever hearing a “chip” make a noise that could not be traced to physical vibration. Even then high power levels where involved at audio frequencies not RF frequencies way outside the range of human ears.

The idea that a “chip” would be responsible for a “buzz” audible from in front of a Plasma TV is implausible to say the least, it would be the last thing on my suspect list.

But now you have been shown to have a limited understanding of things you claim expertise in, that worries me - because you're obviously willing to argue using bad information to make your point or support some advice you've given people before when you may not really know the full consequences.

Play the ball not the man. If you have a valid argument then put it forward.

:)

Funny. And yet the buzz will still come out the underside of the chip - with it never have been eliminated.

As for running frequencies, is it really true that everything runs at those frequencies, just because the main function does? Is that really what your saying now? I just want to make sure.

Digital systems must run at higher clock speeds than the signals they are required to manipulate, typically many, many times higher. Since a Gigabit network hub must handle signals in the 350Mhz plus range the processor is going to run at a faster clock. Even the worlds first digital computer from 1944 ran an effective clock of about 5.8Megahertz or about 290 times the highest frequency a human can hear.

The only explanation I can think of for audio frequencies being present in a network processor chip is if the power regulator was incorporated into the same package rather than mounted externally on the board as is the norm. Even then only the solid state regulator components would be incorporated and they don't buzz. I suspect other components are creating the vibration and the “chip” is vibrating because it is mechanically resonant at the frequency involved.

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You will have to spell it out mate, to use an old term, I'm not catching your drift. :huh:

Once you get to more than a few hundred Hz the sound will be a tone not a buzz (voice frequencies are in the low hundred hertz region), go higher again and you get what most would describe as a whistle.

Look mate, I am not being argumentative for the hell of it, I really have been working on electronics for 35 years and cant remember ever hearing a “chip” make a noise that could not be traced to physical vibration. Even then high power levels where involved at audio frequencies not RF frequencies way outside the range of human ears.

The idea that a “chip” would be responsible for a “buzz” audible from in front of a Plasma TV is implausible to say the least, it would be that last thing on my suspect list.

Play the ball not the man. If you have a valid argument then put it forward.

Digital systems must run at higher clock speeds than the signals they are required to manipulate, typically many, many times higher. Since a Gigabit network hub must handle signals in the 350Mhz plus range the processor is going to run at a faster clock. Even the worlds first digital computer from 1944 ran an effective clock of about 5.8Megahertz or about 290 times the highest frequency a human can hear.

The only explanation I can think of for audio frequencies being present in a network processor chip is if the power regulator was incorporated into the same package rather than mounted externally on the board as is the norm. Even then only the solid state regulator components would be incorporated and they don't buzz. I suspect other components are creating the vibration and the “chip” is vibrating because it is mechanically resonant at the frequency involved.

Placeholder...

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I don't know about the rest of the forum members but I keep getting alerts about this thread because I asked for them because I was interested in maybe buying a P54V20. I would love to see this thread get onto a discussion about the TV and for the esoterics of what is a buzz or a hum or a whistle or whatever taken to another thread where the protagonists can argue the matter to their heart's content.

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More: (in relation to the ones above Owens post)

http://www.red-sweater.com/blog/105/all-wo...iet-macbook-pro

Am I supposed to be surprised that a laptop is not silent?

With main board power supply components, fans, a hard drive and a switch mode power supply to drive the cold cathode fluorescent lamp in the screen there are plenty of potential noise sources.

The “chip” that is supposedly hissing (not buzzing) is a high power switch mode power supply device that can deliver 10 amps continuous and 17 amps peak. With currents like that there is significant emf to cause components and adjoining structures to vibrate, but since the switching frequency is 600kHz only harmonics would be audible, they are not going to be loud and should be easy to control with damping.

The BASH amp is a pulse width modulated design and operates in a similar fashion to a switch mode power supply.

One of these guys thinks there's a buzzing in a chip in his broken monitor:

http://www.fixya.com/support/t408818-fpd1960_model_900g

Monitors, both LCD and CRT have switch mode power supplies which commonly make noise, a “buzz” or high pitched whistle on CRT’s (due to low switch mode frequencies) and a hiss on LCD.

The common theme here is switch mode power supplies; they are the number one cause of noise in electronic equipment after mechanical noises like fans.

I said at the outset that switch mode supplies are the most likely cause of buzz in a Plasma TV, next down the list are components that handle significant power levels at audio frequencies, mostly at 50 or 100Hz. Then comes the panel itself and its driver stages which run at significant power levels and at around 600Hz, a little high for typical “buzz” but not out of the question.

Sound is due to mechanical vibration in the audio frequency band, no vibration no sound. Damp/control the vibration and you reduce or eliminate the sound.

The chance of a “chip” being directly responsible for a significant “buzz” is 1000:1 against, its far, far more likely to be the way the chip is mounted or other passive components, especially coils.

If the buzz is much louder behind the panel its most likely a board and likely fixable at least in part, but significant noise emanating from the front of the panel indicates the panel its self and that’s a different ball game entirely, not much chance of fixing that with a service call.

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I have an old PZ700A 50 inch Panasonic and last night tried as hard as I could to hear any buzz. No matter how close I got I could not hear a thing. Maybe my hearing needs checking.

cheers

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