EEVblog #630 - Soniq LCD TV Troubleshooting Repair - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: June 14, 2014, 10:42:33 am
content: Dave troubleshoots a Soniq L32V12A 32" HD LCD TV

author: Legit-Design
author_rank: Frequent Contributor
timestamp: June 14, 2014, 11:16:12 am
content: Those spring loaded thin probe tips make it look so easy.Quote from: Legit-Design on June 14, 2014, 06:08:31 amDid you forget to discharge the mains filter cap? Thats why you added safety note about one hand behind back?I think it was before you were measuring the ESR on the live stream.

author: bktemp
author_rank: Super Contributor
timestamp: June 14, 2014, 11:30:12 am
content: It looks like the main processor/display controller is not working correctly.You started at the mains input, I would start at the other end: Measuring the signals going to the lcd panel. If there is something wrong, you know it is not the display.The signals to the lcd are typically LVDS: 1 differential pixel clock and 4 differential serial data lines running at 7x pixelclock rate.For a 1366x768 panel the pixel clock should be around 75MHz, depending on the framerate. It may be transmitting odd and even pixels in parallel then the clockrate is halfed and the number of data lines is doubled. Maybe you can use and show some of the advanced trigger features of your scopes to detect gaps in the clock signal.If this clock is not continuously present while the tv is on and displaying an image, there is something wrong with the main processor. Then you should look for other signals failing/changing at the same time.You could turn this repair video into a fundamental video of how to probe highspeed logic signals using a state of the art scope trying to find a fault in a digital logic system.

author: PeterG
author_rank: Frequent Contributor
timestamp: June 14, 2014, 11:40:17 am
content: Why not scrap the Soniq tv and buy your mum a nice LG or similar with a better screen.....Regards

author: nitro2k01
author_rank: Frequent Contributor
timestamp: June 14, 2014, 12:09:46 pm
content: Maybe it's just the different emissivity but I think the CPU heatsink looked suspiciously cold compared to the surrounding PCB area. Maybe you should do some contact temperature probing, as well seeing if adding some airflow makes a difference. I've famously been wrong with my hypotheses before, but maybe some dickhead designer used some form of glue which, instead of conducting heat from the CPU/main chip to the heatsink, isolates it.

author: SeanB
author_rank: Super Contributor
timestamp: June 14, 2014, 01:50:06 pm
content: Just the bright aluminium doing tricks with emissivity. The surrounding hot board says the BGA is definitely getting toasty warm, so most likely the balls are cracked on the chip or on the carrier board. That will explain the symptoms, and the sudden stopping of it responding initially when Dave touched the back side and stressed the board.Might be worth doing a reflow of the BGA from the back of the board, but this one is likely a terminal case.Sell the power supply on eBay and cut your losses. Take the panel apart and see how good the backlights are still and give them with the board, packed in a plastic sleeve and wrapped in bubble wrap then inserted into a cardboard mailing tube ( or some 50mm PVC drain pipe) longer than the backlight tubes and capped with tape and more bubble wrap.I got free a nice LG 22 in flatron display, power supply is fine, dead microcontroller on the small input PCB. Going to scrap it for metal and the backlights, just in case I need them on my other monitor. No screws to open the case, more just prize the 2 parts apart with a screwdriver.

author: tom66
author_rank: Super Contributor
timestamp: June 14, 2014, 02:09:53 pm
content: I think you should do tests of those regulators when it isn't working, as well as when it is. Also, that 1.89V is very high for a 1.8V regulator with a 2% tolerance typical. A high voltage reading can indicate an oscillating regulator due to bad regulator or output capacitor. (It can also indicate something like a low 2.5V regulator, so it's important to check part numbers. The voltage is usually indicated by the last two characters -33 or -18 for example.)I had a cheap 37" LCD TV which had a horrible whine on the audio and it would sometimes only boot with graphical noise all over the panel. It turned out to be a bad capacitor on the output of a buck converter. Testing the output voltage showed 1.79V, for a 1.8V rail that is fine, but it had about 300mVp-p of ripple on it. Once the TV warmed up the ripple disappeared.Also I would try using freeze spray or hot air to see if you can invoke a temperature dependent fault.The 9G Pio Kuro on my wall right now had a bad regulator on the analog A/V board, bargain of the century to get it with that fault.

author: peter.mitchell
author_rank: Super Contributor
timestamp: June 14, 2014, 02:17:40 pm
content: Quote from: tom66 on June 14, 2014, 02:09:53 pmI was thinking this too Dave, you shoulda scope'd the rails.

author: synapsis
author_rank: Regular Contributor
timestamp: June 14, 2014, 03:16:22 pm
content: Last weekend a friend at work gave me a 50" plasma TV that had the intermittent issues then went dead. He knew about bulging capacitors and took a look around, but didn't find any.I went through it and found the 5V standby rail was dead. Turned out a 1000uF cap had bulged *underneath*, the ESR went up to 16 ohms (LCR'd it after I took it out) and blew a Zener diode.I found it with my Flir, but it would've been nice to have a meter like Dave's for that!BTW, Samsung A/V equipment is nice in that they label the pinouts of all the connectors/test points on the silkscreen. This TV was one big power supply.

author: Tothwolf
author_rank: Regular Contributor
timestamp: June 14, 2014, 03:41:35 pm
content: I would definitely suspect faulty joints on the processor due to how it glitched out when Dave touched the side of the case. Maybe tap at it with a plastic spudger and warm it up a little with a hair dryer to see how it reacts? Just the difference in stress on the board from removing and reinstalling the mounting screws could have been enough to cause it to finally fail completely.

author: open loop
author_rank: Regular Contributor
timestamp: June 14, 2014, 04:01:18 pm
content: +1 for poor soldering/cracked BGA balls, liquid flux and heat the proc for 5 mins with a hot air gun, providing that heat sink comes off easy. Unless you know someone who has an IR rework setup.We use at work something like:http://www.pdr-rework.com/e6evolutionMuch better than the cheap stuff you see on eBay.

author: nathanpc
author_rank: Unknown
timestamp: June 14, 2014, 04:05:51 pm
content: What's the impedance of the LoZ mode? Looking at the photos from Dave's Fluke 117 teardown, the only big resistor that looks like would be used in the LoZ mode is this 1k 3W(?) resistor on the side:And you would be pushing it pretty hard while discharging a 400V capacitor.

author: Bored@Work
author_rank: Super Contributor
timestamp: June 14, 2014, 04:43:35 pm
content: Quote from: nathanpc on June 14, 2014, 04:05:51 pm3 kOhmQuoteThe meter is specified for 600 V.

author: tom66
author_rank: Super Contributor
timestamp: June 14, 2014, 05:00:33 pm
content: LoZ is implemented using a PTC, which will increase in resistance as power dissipation increases. I imagine Fluke have tested it will withstand 1kV (or 600V) essentially continuously.

author: Refrigerator
author_rank: Super Contributor
timestamp: June 14, 2014, 05:05:58 pm
content: Maybe sticking it in an oven would fix those problems, you know, the same way people fix GPUs and Xbox360 RRODs.

author: nathanpc
author_rank: Unknown
timestamp: June 14, 2014, 05:19:33 pm
content: Thanks very much for clarifying.

author: SeanB
author_rank: Super Contributor
timestamp: June 14, 2014, 05:26:03 pm
content: Low-Z mode has a voltage limitation if the voltage is above 40V, to a maximum of 30 seconds every 2 minutes or so, otherwise the PTC will overheat and burn out.I have a cheap and rather elderly Stienel voltage check which has a PTC to limit current to the internal LED's and it has this warning for voltages over 40V, while below 40V the PTC will handle power continuously. nice in that it will handle AC or DC from around 5V to 400VAC in a single range, with only 3 neon's to show 110, 220 or 380 VAC or VDC with polarity given by the 2 red led's in the probe case.

author: Bored@Work
author_rank: Super Contributor
timestamp: June 14, 2014, 05:29:43 pm
content: Quote from: SeanB on June 14, 2014, 05:26:03 pmNot that particular Fluke.

author: tom66
author_rank: Super Contributor
timestamp: June 14, 2014, 05:36:29 pm
content: Quote from: Refrigerator on June 14, 2014, 05:05:58 pmThat rarely fixes any BGA soldering issue - the fault will return later. However, it is worth a shot, if only to prove it is the cause. After the more traditional tests have failed.

author: Owen
author_rank: Contributor
timestamp: June 14, 2014, 05:54:02 pm
content: After watching Dave's Video and his differential probes, their comes a question in my mind, that I've always wanted to ask: When do I have to use those second ground bnc\plugs coming right from the BNC input of the probes? Some probes seem to have them some not, i always wondered why? In which situation do they become usefull? Thank you.

author: Rasz
author_rank: Super Contributor
timestamp: June 14, 2014, 05:57:31 pm
content: Wrong video title, shouldnt be called Repair, more like 'Troubleshooting teardown with 20 minutes of talking about repairing'Dont talk about measuring, measure. Put scope behind LDOs on the digital board, power up, look for a change when picture glitches/dies. Even better would be just changing all electrolytic caps on digital board blindly, power it up from separate PSU and check if it still glitches. Swapping all the caps takes less time than talking about swapping themThere is no need of reballing in case its solder joints under BGA, simply heating up main chip until it floats works in 90% of cases.Dave wouldnt last 3 posts on elektroda.pl/rtvforum (forum for people servicing electronics professionally)For people interested in real _repair_ videos I highly recommend this channelhttps://www.youtube.com/user/1servicecoreYes, its in Ukraininan, but important stuff is rather self explanatoryQuote from: tom66 link=topic=32519.msg461764#msg461764date=1402767389.No. It rarely fixes Nvidia GPU BGA problems, because Nvidia had problems between BGA package and silicon, and not between package and pcb. Chip itself is faulty.In case of TVs its usually shitty noPB solder thats the problem, no the chip.

author: Sionyn
author_rank: Frequent Contributor
timestamp: June 14, 2014, 06:13:34 pm
content: thermal degradation of solder joints or Pad cratering that or a failing of the chip with small heatsink

author: Feuerbard
author_rank: Contributor
timestamp: June 14, 2014, 06:15:11 pm
content: its chinese Mstar chip based TV , this soc used in many cheap entry level brand tv like toshiba . lg , samsung e t ?if one dram in bga installed may be is Mstar Saturn 7 like in this SMhttp://archive.espec.ws/files/LG%2026LE3300_26LE3308%20&%2026LE330N%20LED%20LCD%20TV%20SM.pdfthis chinese crappy tv have many problems in firmware , bad or corruption data in spi fplash and probably bad soldering on soc or dram

author: AlphZeta
author_rank: Regular Contributor
timestamp: June 14, 2014, 07:29:13 pm
content: Depending on the age of these LCD panels, sometimes the bond of the flat flex cable to the panel itself (i.e. the ones mated onto the glass) becomes unbounded which manifest itself as unstable images (usually flickering, showing weird color, etc.) and the image can go dark completely.To test whether it is indeed flat flex to the LCD panel, you can apply pressure near the connection on the panel while the monitor is powered on and you should see picture re-appearing or flickering.

author: Zad
author_rank: Super Contributor
timestamp: June 14, 2014, 07:34:52 pm
content: One technique that Dave needs to learn - tapping. Good old-fashioned methodical hitting stuff with a (insulated) stick.Maybe it is because we have had half a generation of systems that run relatively cool, combined with the relative robustness of SMD that we don't get the same dry joint problems that we used to. With intermittent problems like this, tapping the components, PCB and interconnects with a nice soft insulated screwdriver handle is the primary fault detector / inducer.Dave has a temperature controlled reflow oven, it would be worth stripping off the heatsinks and giving it a run through.

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: June 14, 2014, 07:46:59 pm
content: its most likely the T-CON thats faulty . The part number is : 6870C-0303B

author: Jonny
author_rank: Regular Contributor
timestamp: June 14, 2014, 08:38:08 pm
content: Use some of those high end scopes of yours and monitor signals into, and out of, that little board between the main board and LCD and compare data in with data out and might show if signals are failing coming out then that's your issue. If signals going in also appear to go unsettled grab the main board and make use of your reflow ovenLooking forward to that video, nothing to lose

author: croyleje
author_rank: Regular Contributor
timestamp: June 14, 2014, 10:05:52 pm
content: Just a thought but wouldn't the external VGA output be easier to probe and check the timing on or at least be able to see if there is a glitch from when the it is working and isn't working. Also when Dave first kinda leaned over the tv and grabbed the side the pic dropped out seems like some kind of connection issue to me. Just my thoughts.Jason

author: tom66
author_rank: Super Contributor
timestamp: June 14, 2014, 10:15:59 pm
content: Quote from: fluxcapacitor on June 14, 2014, 07:46:59 pmDisagree; the T-con going bad usually causes a number of specific problems. This T-con is also memoryless, it's an LVDS format converter. A fault where the boot logo is OK would not be one of those. The main board is the only part that can differentiate between these.

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: June 14, 2014, 11:37:52 pm
content: Quote from: tom66 on June 14, 2014, 10:15:59 pmYes ,you`re right tom .

author: NiHaoMike
author_rank: Super Contributor
timestamp: June 15, 2014, 12:41:48 am
content: If the panel accepts the same data format as the broken one in that salvaged monitor, you could try using the driver board out of that monitor.

author: pickle9000
author_rank: Super Contributor
timestamp: June 15, 2014, 04:09:59 am
content: The EEVBlog curse is broken?Hard to believe.

author: VK3DRB
author_rank: Super Contributor
timestamp: June 15, 2014, 05:55:35 am
content: You don't need an expensive differential probe to scope the primary side of the power supply. Just plug the TV into a mains isolation transformer, then you can scope it. For safety reasons alone, it should be mandatory to use an isolation transformer before even attempting to power the TV up with the back off.You should consider using the back of a screwdriver to flex the PCBs slightly to see if the intermittency of the problem changes.Another suggestion is to buy yourself a can of freeze spray and with a heat gun as well, see if the intermittency changes with cool/heat. If you see that it is changing, then use cardboard barriers to isolate the area where the offending dry joint or intermittent capacitor exists. This is a very effective technique for symptoms as those shown on the video.From an ethical perspective, it is good practice to bias towards fixing something rather than throwing it away.

author: Stonent
author_rank: Super Contributor
timestamp: June 15, 2014, 06:59:18 am
content: Quote from: fluxcapacitor on June 14, 2014, 07:46:59 pmHad a cheap 32" 720P Westinghouse TV a guy at work was going to trash but said I could have it because I liked to play around with electronics stuff. It seemed ok for about 20 minutes and then started bleeding red into the picture, then getting vertical red lines, then blocks.I contacted a TV part supplier "ShopJimmy" and they sell you parts based on the symptoms, and he said definitely a T-CON board. $25 later I had a fully functioning TV. Since it was bigger than my tube TV, it became the main TV.Though mine didn't have problems with it not turning on like Dave did, so who knows.It does give me an idea though, how about a video of Dave taking the TV to a TV repair shop and doing a tour and video them doing some troubleshooting? Might make for an interesting video.

author: M0BSW
author_rank: Frequent Contributor
timestamp: June 15, 2014, 08:12:59 am
content: Quote from: Legit-Design on June 14, 2014, 11:16:12 amI saw that to,could it have been the revenge of that bloody hammer, seriously switch mode capacitors those buggers hold some serious voltage, and I didn't see him use a bleeder resistor on that big one, maybe he did off camera,easily done though, hasn't the fluke 115 or 117 got a capacitor discharge on it,I seem to remember they had .

author: EEVblog
author_rank: Unknown
timestamp: June 15, 2014, 08:15:29 am
content: Quote from: wilfred on June 15, 2014, 03:57:16 amI was wondering if anyone saw that...Yes, fixed in the nick of time, had to pick my mum up and she wanted her TV working again! Footage is at the lab, so no video tonight.

author: M0BSW
author_rank: Frequent Contributor
timestamp: June 15, 2014, 08:17:15 am
content: Quote from: EEVblog on June 15, 2014, 08:15:29 amwhat was the fault in the end,looking forward to the video, to add to my experience in fault finding.

author: FreeThinker
author_rank: Frequent Contributor
timestamp: June 15, 2014, 09:59:10 am
content: Enjoy that lamington.

author: M0BSW
author_rank: Frequent Contributor
timestamp: June 15, 2014, 11:41:12 am
content: Ah Yes , I see you fixed your Mums TV then Dave

author: Jörg from Germany
author_rank: Newbie
timestamp: June 15, 2014, 03:19:12 pm
content: Hey Dave,i have an idea, what is wrong with your LCD TV. If the caps are good dimensioned, the first thing which fails are the ccfl. They are burnd out. The inverter has to rise the voltage for the ccfls more and more, and then, if the voltage is too high, the inverter interfer all the digital and dsp stuff. I'm not sure why this happens, because i don't know, how the inverter controlls the voltage, perhapps it changes the switching frequency or duty cycle or what ever.To check, if this is the case, you only have to stick out all ccfls, and run the "sucker". You need a bright light, to see, if the LCD shows something.Would be interested, if this is the problem.GreetingsJörg

author: synapsis
author_rank: Regular Contributor
timestamp: June 15, 2014, 03:43:42 pm
content: Quote from: EEVblog on June 15, 2014, 08:15:29 amSo Dave's doing cliffhangers now?"Next week on EEVBlog: What was wrong with the TV and who shot JR?"

author: Stonent
author_rank: Super Contributor
timestamp: June 15, 2014, 08:57:04 pm
content: Quote from: synapsis on June 15, 2014, 03:43:42 pmAnd in the end, it will all just be a dream.

author: notsob
author_rank: Frequent Contributor
timestamp: June 15, 2014, 11:30:03 pm
content: METAL watch band on arm whilst over 240V - BIG NO NO Dave

author: tom66
author_rank: Super Contributor
timestamp: June 16, 2014, 12:42:36 am
content: Quote from: Jörg from Germany on June 15, 2014, 03:19:12 pmInverters don't compensate for ageing CCFLs, unfortunately. They are constant-current sine wave drive, with a small range of acceptable voltage which allows for some drift, especially from bulb to bulb. Modulation of bulb current is done by duty-cycle modulation of the high frequency drive current, but the modulation is only there to maintain the bulb current. A bulb at EOL would simply light for a few seconds then extinguish as the over-voltage or over-current protection mechanism engages,

author: Jörg from Germany
author_rank: Newbie
timestamp: June 16, 2014, 05:59:20 am
content: Of course, You are right, it will be a current control.Normally in the case of EOL of CCFL, the bulb would flicker at the beginning when the bulb is cold, like you wrote.Now i also read, that Dave fixed it, so it seems to be an other problem.But how ever, in my experience, a bulb working at EOL can cause several failures.

author: elektron
author_rank: Newbie
timestamp: June 16, 2014, 09:35:41 am
content: watcher's activities list on eevblog:- watch a guy scrapping the basement for old electronics- watch the same guy walking at electronics fairs and ... do nothing- see non sense - "repair" videos (i can't remember of any video of him actually repairing anything)- see fotographs from postcards packed together with adaptor boards.- see how you mount a camera on a bench- learn to solder ?not to mention, the hidden advertisements, emotional catches from showing his child (using the child for this purpose dave is inqualificable) ... you add to the list.best to all.peace.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: June 16, 2014, 10:23:41 am
content: Quote from: elektron on June 16, 2014, 09:35:41 amYou forgot honesty, Dave always says everything exactly like it. One time he was so honest it made me laugh. I don't think Dave would have career as politician.

author: tom66
author_rank: Super Contributor
timestamp: June 16, 2014, 11:13:17 am
content: Quote from: Jörg from Germany on June 16, 2014, 05:59:20 amMost LCD TV inverters I've found will simply cut out after a couple of seconds and this is a latching error which will only disappear after power is removed again.

author: brabus
author_rank: Frequent Contributor
timestamp: June 16, 2014, 12:40:32 pm
content: Quote from: elektron on June 16, 2014, 09:35:41 amWhat are you offering on your channel? Do you have one? Let's make a comparison.Or maybe jealousy is just a bad beast.Peace!

author: elektron
author_rank: Newbie
timestamp: June 16, 2014, 12:54:41 pm
content: Quote from: brabus on June 16, 2014, 12:40:32 pmnothing really and no, i dont have a channel and that's because i'm not the one selling concepts around.if we were to compare something, let's compare similar blogs across the spectrum.your pick.. let's start with 3 proposals and rank them on (negociable) criterias:- electronic insight offered- degree of time "loosing"- actuality and news- [add more]don't know which other criteria fits in, but eevblog fails the most and wins the "nerd entertainment" section.any other criteria you might find usefull. please add. excuse my english. i'm not a native speaker.

author: rob77
author_rank: Super Contributor
timestamp: June 16, 2014, 01:02:34 pm
content: Quote from: elektron on June 16, 2014, 09:35:41 amno-one is asking you to watch Dave's videos - if you see something on TV you don't like - you change to different channel. so please do the very same in this very case as wellI like Dave's videos - i'm watching Dave's channel instead of TVDave is a great guy not afraid of being honest and share his opinion in the public !and regarding the postcards and unsuccessful repair videos - we all like those ! either you pick up some information, or you learn something or just watching them for entertainment. i rather watch Dave's mailbag than an episode of some stupid TV series...if you don't like it, then go and watch something else ! it's so simple !

author: elektron
author_rank: Newbie
timestamp: June 16, 2014, 01:09:07 pm
content: You can't handle criticism too well.Ofcourse I follow different blogs and information sources. There is also a subtle difference between "don't like" and logicaly present some arguments.You seem to agree that a video called "repair video" consisting of CAP checkings to be enjoyed because is fun. Which is exacly my point. Well.. that's logic too.. sleep tight.p.s from the registration terms and conditions we see:"5) This is an electronics forum, so try to stay on-topic."so ... yes.. dave is way off topic with these pseudo repair videos, but we need to stick on topic. see how many ideas of repairs popped up from users commenting to the video, not from the initator of disccusion. i'm don't know about you but I like to think. so let's count. he checked caps, you suggested checking logical buses, he checked power regulators, you indicated probing with a scope to detect a difference when glices occured. see my point ?i'm not sure about "my mom tv story" either. it sounds to me like a pretext, because it made me think at the following dialog:day1:- son?- yes mom !- come here!- just a second. i have to post something..- bloody blog.. when he will take a real job...?- ok.. what is it ?- my tv just died.- ummmm- can you repair it ?- sure mom.. why not.. i will film it.. and post it so everybody sees it..day2:- well ?- no mom. it is beyond economic repair (?)- really ? so i need to buy another ?- yeap..that was fun.. not the video..

author: HP-ILnerd
author_rank: Frequent Contributor
timestamp: June 16, 2014, 01:40:48 pm
content: Quote from: elektron on June 16, 2014, 09:35:41 amHere's a couple (there are more), now you have something to remember!:http://www.eevblog.com/2012/09/11/eevblog-347-bad-cap-lcd-monitor-repair/http://www.eevblog.com/2013/10/24/eevblog-539-rfid-tag-card-repair/

author: elektron
author_rank: Newbie
timestamp: June 16, 2014, 01:47:38 pm
content: Quote from: HP-ILnerd on June 16, 2014, 01:40:48 pmyes. these are a bit better, but still not good enough. these are really really basic things. ofcourse, for a beginner, probably that's OK (with the note: begginers should probably first read some books, then be entertained), but yes.. ok for beginners.from a random pick.. compare with this:

author: elektron
author_rank: Newbie
timestamp: June 16, 2014, 01:55:43 pm
content: stick with the "idiot" version.meanwhile explain two things:- "care" and "careless" in a blog context. and- what are the things you disagree / agree

author: nixfu
author_rank: Unknown
timestamp: June 16, 2014, 02:08:25 pm
content: WTH? I thought Dave said he would post the other video with the final fix? Its been a long time now.Are we going to have to wait until the fall premiere of the next season of eevblog until we see the conclusion of this cliffhanger?WILL DAVE FIX THE TV IN TIME OR WILL IT EXPLODE?WILL DAVE GET 240V THROUGH THE WATCH AND BE FLOWN ACROSS THE ROOM ON CAMERA?WILL DAVE CUT THE BLUE OR THE RED WIRE?WILL DAVE SAVE HIS MARRIAGE AND HAVE A GRATEFUL MOTHER IN LAW?STAY TUNEDSAME TIMESAME CHANNEL

author: synapsis
author_rank: Regular Contributor
timestamp: June 16, 2014, 02:34:52 pm
content: Man... There sure seems to be a number of whiners about Dave's videos on Dave's forum.It's easy to be so critical when you don't know how much work goes into making videos and running a forum. Most of the time it's a thankless job.So he didn't fix the TV in one video, big deal. He spent a number of videos on a piece of test equipment (forgot what it was) and never fixed it. Then in other videos the solution is as simple as an AC line filter. People will bitch either way. If you learn from Dave's line of thinking and troubleshooting methods, that's more important than if he actually fixed the TV.

author: M0BSW
author_rank: Frequent Contributor
timestamp: June 16, 2014, 03:00:41 pm
content: A while ago I got really fascinated by faultfinding and repairing, I know seems to be a black art, however at 60 years old, I have found a TV repair shop thats more than willing to help me along, and I'm loving it so much, the young guys in there seem genuinely pleased to help an old git,I have learned some of the boards and what they do.now I have forgotten something though, is it the inverter boards,Y main,Y sustain,X main , buffer board or T Con that run flat out, I think it's the inverter board,and is it, if the inverter board goes high damage will occur to the other boards, I maybe totally wrong which means later when I go down to the shop,Ill have to go through the whole excercise again.

author: HP-ILnerd
author_rank: Frequent Contributor
timestamp: June 16, 2014, 03:06:11 pm
content: Quote from: synapsis on June 16, 2014, 02:34:52 pmNo kidding. The thing I like is that level of transparency with Dave is very high. He shows whatdidn'twork. He shows it isn't all necessarily fixable, or worth fixing.The real-life nitty gritty involves failure, and being willing to have your failures in public for everyone to learn from is a public service.Real life isn't like TV and movies where engineers figure out the problem by the end of the show...

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: June 16, 2014, 03:09:21 pm
content: Quote from: elektron on June 16, 2014, 01:47:38 pmDo you have any random videos of your own that we can watch ?

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 16, 2014, 07:59:02 pm
content: Hi,There was no sign of an inverter board on that TV, so i'd assume it is a LED back-light.There was the common 25v supply used by inverter boards, unless the board was hidden under the white plastic base.

author: bktemp
author_rank: Super Contributor
timestamp: June 16, 2014, 08:10:58 pm
content: The ccfl inverter is embedded into the main power supply (big transformer with yellow tape around it). There are two cables going from there to the right and left side of the tft panel.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: June 16, 2014, 08:11:57 pm
content: Quote from: Mr Smiley on June 16, 2014, 07:59:02 pmSee those thicker than normal cables and special type of connector with far apart spaced pins. Those look like ccfl backlight to me. But I don't think it's the backlight since it was on most of the time. LED backlight doesn't need that type of cable or connector. Like others said already looks like digital board problem.

author: eevbstedt
author_rank: Contributor
timestamp: June 16, 2014, 10:19:07 pm
content: Has anyone been able to view Part 2? There's a link in the description to this:

author: eevbstedt
author_rank: Contributor
timestamp: June 16, 2014, 10:37:01 pm
content: Bango ... it's up. Thanks Dave!

author: tru
author_rank: Regular Contributor
timestamp: June 16, 2014, 10:47:47 pm
content: I have fixed a few LCD monitors, bad caps, bad resistors, these are easy problems that I could fix.Then I came across 2 monitors (manufactured year 2009) that have the 2 seconds backlights turning off, I couldn't fix them and told friends that the electronic boards were good, all good caps so I think is the ccfl, however I don't have any spare lamps to test with to find out for sure. I just gave up because you have to factor in personal time for such small gain (LCD monitors are cheap now).I can't wait to see what Dave's problem is. My guess is loose connectors?I can't believe there are idiots here registering just to whine, please make your own video and see if you can do better. I am pretty sure Dave shared his videos for people who want to watch them. Also I don't understand why he should take any criticism from his own forum?Personally, I prefer to watch Dave's videos over others because they are entertaining, realistic and he does not try to show off. People if you don't like it don't watch it, it is simple really go watch other videos.

author: tom66
author_rank: Super Contributor
timestamp: June 16, 2014, 11:00:10 pm
content: Quote from: M0BSW on June 16, 2014, 03:00:41 pmCertain older Samsung and many modern Panasonic plasma TVs will damage Y-buffer boards (SU/SD or SM) when the Y-sustain (SC board) fails.

author: Spivey
author_rank: Newbie
timestamp: June 16, 2014, 11:04:36 pm
content: Well, I am an idiot who registered here just to say that I really enjoy Dave's videos. With this one, he could have waited until he'd fixed it and edited it down to look like he went straight to the problem with no hesitation. And I'm sure someone with a lot of TV repair experience would have gone to it straight away. But we all know the feeling of taking the back off something we don't have a lot of experience with. That's what this video shows, and people are having a lot of fun speculating and saying what they would try next.If you think that boring, badly-shot lecture on PLLs is better, you're welcome to it. Give Dave a fair go! He's Australian, not Austrian!

author: tom66
author_rank: Super Contributor
timestamp: June 16, 2014, 11:16:32 pm
content: Nice fix Dave, I have fixed quite a few with that same connector. Same issue, I think it is related to the connector being flexed during manufacture perhaps.A Toshiba 32" LED Smart TV, and a 26" cheapie.

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 16, 2014, 11:38:55 pm
content: Hi,Not meaning to be a kill-joy, but was it a good idea to completely cover that board with tape, any possibility you may have further problems with temperature build up from the now enclosed ic

author: Rasz
author_rank: Super Contributor
timestamp: June 16, 2014, 11:49:11 pm
content: Quote from: tru on June 16, 2014, 10:47:47 pmbenQ/dell/acer?look for c5707 transistors in the inverter, those die producing effect you describe

author: tru
author_rank: Regular Contributor
timestamp: June 17, 2014, 06:55:05 am
content: Quote from: Rasz on June 16, 2014, 11:49:11 pmThanks will try looking at those transistors.25" Hannspree HSG1064 (I'm surprised all caps are Nichicon)19" HP (Rubycon caps)Just realised I can try taking out the 19" ccfl from the HP to test on the 25" one.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: June 17, 2014, 07:56:58 pm
content: Quote from: elektron on June 16, 2014, 12:54:41 pmShit, I think EEVblog should give Dave the boot and get new host for the show. Maybe someone who knows more about eletronics?

author: N2IXK
author_rank: Frequent Contributor
timestamp: June 17, 2014, 08:44:02 pm
content: My only complaint is that if Dave was going to do a TV repair video for blog #630, he should have done the famous RCA 630 chassis, which was the first mass-produced TV set, introduced just after WW2:http://www.tvhistory.tv/1946%20RCA%20630TS%20TV.htmLike the IBM PC in later years, dozens of manufacturers copied this design more or less completely for the first few years of TV. 630-derived sets are still widely available and popular among the vintage TV crowd.

author: rob77
author_rank: Super Contributor
timestamp: June 18, 2014, 02:35:48 am
content: Quote from: N2IXK on June 17, 2014, 08:44:02 pmmy 2 cents..there are lot of numbers related to iconic stuff, but you simply can't make all the videos according to those numbers... the EEvblog #555 made sense - everyone knows the 555 timer or at least heard about itbut for example the 630 chassis - it's definitely a milestone - but only a few know about it (for example i was not aware until i red you post).

author: EEVblog
author_rank: Unknown
timestamp: June 18, 2014, 02:56:34 am
content: Quote from: rob77 on June 18, 2014, 02:35:48 amYep, I've never heard of it.