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The Inbuilt Digital Tv Tuner Has Failed, Is It All On One Board In The Tv?

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My Panasonic TV it appears has developed a fault, the digital TV tuner has failed and just gives a black screen. I know the signal is fine as my Digital TV card in the PC still has a signal so it appears the internal digi box has failed. The analogue TV works and the scart and HDMI connectors are fine.

Is everything contained on a single board inside the TV? I'm rather hoping it's like the on/off switch which failed on my previous TV as I ended up with a new TV as they couldn't fix it under the extended warranty as the part was obsolete.

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There are a few threads relating to Panasonic tuners dying over on AVForums which might be worth a try. Alternatively a google search with model no may help.

Have you tried to get latest firmware?

Have you checked cable from wall to TV for dry solder joints?

Have you tried retuning or restoring default settings and reinstalling?

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There are a few threads relating to Panasonic tuners dying over on AVForums which might be worth a try. Alternatively a google search with model no may help.

Have you tried to get latest firmware?

Have you checked cable from wall to TV for dry solder joints?

Have you tried retuning or restoring default settings and reinstalling?

I can't retune, tried it last night. I can bring the menu up, but when I go to the tuning bit it just disappears.

Looks like it's an intermittant fault, just had it working for 10 secs and then it disappeared again.

I'll have a look at the link later.

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I can't retune, tried it last night.  I can bring the menu up, but when I go to the tuning bit it just disappears.

Looks like it's an intermittant fault, just had it working for 10 secs and then it disappeared again.

I'll have a look at the link later.

#You might just have to go out and buy a standalone Freeview box and connect via scart or HDMI. Its what I do anyway with my LG, not because the onboard tuner has broken, it just doesn't support HDTV transmissions.

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#You might just have to go out and buy a standalone Freeview box and connect via scart or HDMI. Its what I do anyway with my LG, not because the onboard tuner has broken, it just doesn't support HDTV transmissions.

I don't need to buy anything it's got an extended warranty, if they can't fix it I get a shiny new TV. This happened with my Samsung the on/off switch had broken and they couldn't get the part so I got a new one.

I'm hoping they have similar problems and can't fix it so I can get a new one.

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First links here look promising.

These mostly refer to a range of Panasonic PVRs utilising the same (or close variants of the same) tuner boards as one another. They seem to report what looks like your problem as a common fault. Whether your TV shares this tuner board I've no idea. If it does, the repair is simple and cheap so long as you can wield a soldering iron. A capacitor gets fried when writing to the EEPROM that stores channel information. Let's hope it's that simple.

Now I've said that your problem will be different and terminal.

Edited to add that I've just seen the previous post and advise not taking a soldering iron to a product under warranty. Yes, let's hope they can't fix it and have to replace yours with a bigger and better model as replacement.

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First links here look promising.

These mostly refer to a range of Panasonic PVRs utilising the same (or close variants of the same) tuner boards as one another. They seem to report what looks like your problem as a common fault. Whether your TV shares this tuner board I've no idea. If it does, the repair is simple and cheap so long as you can wield a soldering iron. A capacitor gets fried when writing to the EEPROM that stores channel information. Let's hope it's that simple.

Now I've said that your problem will be different and terminal.

Edited to add that I've just seen the previous post and advise not taking a soldering iron to a product under warranty. Yes, let's hope they can't fix it and have to replace yours with a bigger and better model as replacement.

Taking a soldering iron to it may cause a bit of a problem :) Not sure if that comes under the accidental damage part of the warranty :lol::lol:

It's my hope too that it's screwed, I quite fancy a LED 37" TV, with at least 3 HDMI ports.

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First links here look promising.

These mostly refer to a range of Panasonic PVRs utilising the same (or close variants of the same) tuner boards as one another. They seem to report what looks like your problem as a common fault. Whether your TV shares this tuner board I've no idea. If it does, the repair is simple and cheap so long as you can wield a soldering iron. A capacitor gets fried when writing to the EEPROM that stores channel information. Let's hope it's that simple.

Now I've said that your problem will be different and terminal.

Edited to add that I've just seen the previous post and advise not taking a soldering iron to a product under warranty. Yes, let's hope they can't fix it and have to replace yours with a bigger and better model as replacement.

come IIRO..Denninger reported this fault and included the repair on his blog some months ago:

Posted by Karl Denninger in Consumer at 22:04

(Page 1 of 419, totaling 2091 entries) » next page

Chinaman Fails To Hose American

Back in November of 2009 I penned a rant to President Obama, with one of the topics being known-defective Chinese capacitors that have a propensity to short out internally and explode.

There are many sites on the Internet that have talked about this, but it has not been widely reported in the media - at all.

These known-defective components are found in virtually everything electronic-related. Nearly all electronic devices have electrolytic capacitors in them - the purpose of these devices is to smooth electrical currents, much like a shock absorber does in a car. Without them working properly circuits either don't work at all or become unstable.

If you've ever heard a "snapping" noise from some piece of electronic equipment, shortly before or concurrently with it ceasing to work, you almost certainly have run into one of these known-defective components.

Yet despite knowledge of the fact that these things are in literally everything - phones, computer board, power supplies, TVs, monitors and other products - there has been no recall that I know of issued.

The ugly on this is that these defective capacitors almost always last just long enough for whatever it is to get out of warranty - typically a year or two - and then they short out internally. The reason for the failure has to do with a defect in the electrolyte that is contained in them - it is contaminated, and over time corrodes the insulation inside the component until there is a short-circuit. At that point the capacitor heats rapidly, the electrolyte boils, and the scored "emergency vent" (really just an intentional weak spot in the case) ruptures, making a popping or snapping sound.

Most consumers throw the offending device away, since it's out of warranty. But before you do that the next time, consider fixing it instead.

In some cases the offending components are what are called "surface mounted", and are damn near impossible to replace without very expensive "rework" stations that no individual is going to have. I have been building and fixing electronic devices for 30 years, and I don't own one - a good setup to do this sort of work costs thousands. But many times the the components in question are through-hole, and if they are they're easily replaced.

Yes, you really can fix them in that circumstance, and a good part of the time that's the only thing that's wrong with your device. The components in question are inexpensive - typically well under a dollar apiece!

The other day one of my four monitors started acting up when it was cold. It would not turn on - but if I left it on for a few minutes, it would start up and work normally. This is a symptom of failing (but not yet totally dead) capacitors - in this case, in the backlight power circuit for the monitor.

Not wiling to throw a perfectly good $300 monitor in the trash for $5 worth of parts, I decided to fix it.

First, we disassemble the case - there are three screws on the bottom that must be removed, and then carefully lifting a screwdriver is inserted into the side to pop the side catches on the case free, as shown below. I began by placing the panel face-down on the blanket on my bed so the screen would not get scratched while I disassembled it (click any of these for a larger image):

You can see the tabs here that I'm releasing as I pull the back of the case off. I use a small screwdriver to pry the case (gently - don't break them!) free to release the tabs as I go along.

With the back off there are three sets of cables that have to be disconnected from the electronics pod that run to the screen itself. One is under an aluminum shield that has to be removed first. When you disconnect there never pull on the wires - always find the release tab or tabs (there always is one!) and release it, then pull the connector straight out. Use a small screwdriver if you need something to pry with but do not force any of these - they are delicate and will break. Make sure you either remember or label what goes where - in some cases you can plug the wrong thing in the wrong place - this is not usually possible, but that mistake, if you make it, usually ends in the "magic smoke" being released from the device.

(As an aside, if you wonder what "magic smoke" is, all electronic devices contain it. Proof of this is found in the fact that if you ever let it out the device will never work again... )

And finally, the signal cable to the actual LCD panel. Notice the twisted wires - they're twisted like this so as to cancel any interference. This connector is somewhat fragile as it has a lot of pins and is very fine "pitch" (that is, little space between the pins) - be careful when disconnecting it.

Once we have the connectors disconnected we can remove the electronics module by lifting it off and exposing the two boards inside. The one that we're interested in is the power board. We first must disconnect the power board's cable to the signal board, shown here unplugged - the latch on this one is hidden but it's there - don't just pull the wire!

Now we can remove the power board be removing the three screws that hold it in place, along with the little bracket in the center that covers the AC receptacle. Having done that it lifts free and clear, and we can see the problem:

Goddamn Chinese junk components! Told 'ya so!

Note the cylindrical aluminum things wrapped in plastic with a big "minus" sign printed on them and scored tops. The left two are defective - the leftmost one is bulging and the center one has actually exploded. The right one looks ok, but who knows for how much longer that will be the case. There are two more made by the same company on the board (not shown) that also look ok.

We're going to change all of them - why take something apart twice when you can fix it right the first time? Besides, we know this company's components are utter trash and as such I sure as hell don't want them in there any more.

The correct replacement values are printed on the sides of the capacitors. In this case we need two 820uf 25V capacitors, one 330uf 25V capacitor, and two 680uf 25V capacitors (the latter two are not shown.)

Digikey has these available via mail order for a few dollars. You need to match the lead type (in this case axial, that is, both come out the same end), and value (330uf, 680uf and 820uf) and working voltage (in this case 25V.) Manufacturer is not important; indeed, you probably don't want to match the manufacturer (since the original folks had such wonderful quality control in the first place!)

You will also need a de-soldering iron, which is simply a soldering iron with a "sucker" bulb on it. You use it to heat the solder and then suck it into the bulb so you can remove the defective components. A regular small soldering iron and some solder is then used to mount the new components.

Here I am removing one of the bad capacitors by simply heating the solder until it melts, then using the "sucker" to aspirate it:

Once I've removed the five bad parts I simply replace them and solder the new ones in place. Note that electrolytic capacitors are polarized - that is, they have a positive and negative end. The board is marked with a "+" on the positive terminal, and convention is that the capacitors themselves are typically marked on the plastic wrap with the negative terminal. In this case the non-soldered side of the board is also marked with a black semi-circle where the negative side goes.

DO NOT INSTALL THEM BACKWARDS. If you do they both won't work and likely will immediately explode when the power is turned on.

The only other caution is to check for short circuits. There are other components and "traces", or strips of copper, on the board you're working on. It is essential that you not "bridge" the soldering point you're installing the capacitor into (the hole and pad around it) to any of the other devices or circuits on the board. Use a magnifying light if you need it (I didn't used to when I had 20 year old eyes, now I use one!)

If there is a fuse on the board check it to see if it has popped. If the device would not turn on at all (power light doesn't come on) it's a good bet when the capacitors popped they caused the fuse to blow. If so, replace it - but only with the same rating printed on the fuse! Never, under any circumstances, bypass a safety fuse - they're there to prevent a fire. Note that if the fuse is popped (in this case it was not) there's a decent chance other components on the board were damaged by the capacitor failure and your repair attempt will fail. But if it does, you're only out about $5, so what the hell, right?

When you're done the board will look like this:

All five replaced capacitors are visible in this shot. Notice no bulges and no exploded ones. If you're observant you'll notice that there's also a huge filter capacitor in the primary power circuit (the really big one in the center) - it looked ok and the blue power light was coming on normally, so I left it alone. (If the power refused to come on at all I probably would have changed this one as well - just for good measure.)

Reassembly is the reverse; make sure you don't pinch any wires or plug in any connectors backwards. Most are keyed to prevent this - if anything is hard to plug back in, check it - don't force it. The back snaps back on and the three screws along the bottom replaced.

Then you just plug in your power and DVI cord and push the button....

All fixed, good as new.

Total cost? About $15 to have enough parts to do BOTH (the one to the right is working fine, but probably will die too - same model, so it takes the same parts and probably has the same parts from the same garbage Chinese company in it) including $5 in postage.

Time required?

30 minutes, start to finish.

It took me longer to write this post than it did to fix the monitor.

Neither our government or our so-called "consumer protection" agencies should be sitting still for this crap. This problem has been known for about five years now, and results in thousands of monitors and computer boards going to the trash can every single day as a result of a latent manufacturing defect. A good percentage of personal computer power supply, graphics card and motherboard failures are caused by these defective components. I'm willing to bet that a plurality, if not a majority, of consumer electronics failures are traceable to this problem. I have personally had two graphics cards fail in the last year as a result of this Chinese crap and now a monitor. The graphics card parts were surface-mounted and as such I couldn't reasonably repair them - that sucked. But the monitor was through-hole, and thus easy to fix.

You should not pay for any of this, but it is just one more example of so-called "consumer agencies" that are charged with protecting you from shoddy garbage made in China - but they don't and won't.

All that's left for you to do is fight back, and instead of spending more money on more Chinese crap fix what's broken, denying these thieving crooks a second sale that should never happen.

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im also wondering about my pioneer stereo amp that broke a few weeks ago

turns on fine and will remain on but when you try play a song it will turn itself off after maybe 30 seconds or a minute

any electrical gurus here? sounds like a capacitor to me maybe ; the amp is maybe 15 years old or so the problem started maybe 2 weeks back.all i have tried so far is blowing the dust out with a compressor which hasn't helped.

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im also wondering about my pioneer stereo amp that broke a few weeks ago

turns on fine and will remain on but when you try play a song it will turn itself off after maybe 30 seconds or a minute

any electrical gurus here? sounds like a capacitor to me maybe ; the amp is maybe 15 years old or so the problem started maybe 2 weeks back.all i have tried so far is blowing the dust out with a compressor which hasn't helped.

Perhaps it no longer likes the music? :P

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Send it to them and see what happens ? Could be a plan. They will probably give you a better answer than someone on here....;)

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I would suggest it is a thermal breakdown in one of the components. When the component starts to warm up the insulation inside the part breaksdown due to the heat it is generating and shorts out the circuit but not enough to blow anything as it could be an audio signal of +/- 1volt pp.

Sorry not much help.

im also wondering about my pioneer stereo amp that broke a few weeks ago

turns on fine and will remain on but when you try play a song it will turn itself off after maybe 30 seconds or a minute

any electrical gurus here? sounds like a capacitor to me maybe ; the amp is maybe 15 years old or so the problem started maybe 2 weeks back.all i have tried so far is blowing the dust out with a compressor which hasn't helped.

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Send it to them and see what happens ? Could be a plan. They will probably give you a better answer than someone on here....;)

I was just wondering if we had any TV engineers on here who may just know if the tuner goes it's the entire board inside that needs replacing or if it's like a PC where you can just swap components in and out with ease.

As I've already said I'll be arranging for the experts to look at it next week.

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What you normally fins is that the basic TV is made for a world market to save multi tooling. The sets that are destined for the UK market will have a UK tuner however there are tuners that can be software configured for multiple markets. A good example of this are DVD players were they are regionalised but with a few button presses you can change the region. Which ever way they are normally easy to change but I am not familiar with Panasonic.

I was just wondering if we had any TV engineers on here who may just know if the tuner goes it's the entire board inside that needs replacing or if it's like a PC where you can just swap components in and out with ease.

As I've already said I'll be arranging for the experts to look at it next week.

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im also wondering about my pioneer stereo amp that broke a few weeks ago

turns on fine and will remain on but when you try play a song it will turn itself off after maybe 30 seconds or a minute

any electrical gurus here? sounds like a capacitor to me maybe ; the amp is maybe 15 years old or so the problem started maybe 2 weeks back.all i have tried so far is blowing the dust out with a compressor which hasn't helped.

Could be biasing issues, failing psu / decoupling caps, diodes, transistors you name it. Take it to a good technician who is prepared to work to component level (I know not common these days but they do exist!!!) and they shouldn't charge the earth to fix it. Otherwise sell on ebay as spares repairs or give away on freegle ;)

Could try Electrotech forums or similar...

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Well it's completely failed now, it switches on and all you have is the red light glowing say it's on but nothing on screen.

Hopefully this means it's completely fooked and needs scrapping. I'll be gutted if it can easily be fixed I want to do my bit to help the economy and get a TV upgrade.

The one downside is that I'll have to watch some of the football on our 19" TV.

Still hopefully it won't take too long for it to be scrapped and I get a new one. However I'm amazed at how many TV's I've been through in 10 years it works out and something like 1 every 2 years, although we got through 3 just as I moved in with the wife because the whole batch appeared faulty and we kept taking them back. The Samsung must have lasted about 3 years before the on/off switch broke. This Panasonic has lasted just a little over 4 years.

Looks like the cheap Chinese components are helping to create perpetual demand.

Just got to wait till tomorrow when hopefully the engineer comes out and shakes his head and tells me it's dead get a new one.

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  • 259 Brexit, House prices and Summer 2020

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