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jurb6006@gmail.com: Jul 05 04:30AM -0700 The solution is simple.   Figuring out what the engineers did wrong $ 150 Figuring out a solution $ 100 Implementing the solution $ 75 Putting up with an asshole $ 100.   Total $ 425, and if the math is wrong you pay it anyway. If you want a rush job double that. And it is $ 20 per phone call and $ 5 per email.   Plus all applicable taxes of course.

Tim Schwartz <tim@bristolnj.com>: Jul 04 06:31PM -0400 On 7/4/2018 9:27 AM, root wrote: > would cost $1400.   > The tv was top-of-the line 3D 240Hz and cost $3300.   > Is this representative of Samsung?   It is not representative of Samsung, it is representative of the technology. However, this is often the case with TV's. I remember 30 years ago pricing a replacement CRT for a 19 inch Sony Trinitron. Dealer cost was around $325, at a time when you could buy a new 19" Sony for $299.   While it is disappointing that it failed in 4 years, that it is not worth buying the part does not surprise me.   Regards, Tim Bristol Electronics

Jeff Liebermann <jeffl@cruzio.com>: Jul 04 07:43PM -0700 On Wed, 4 Jul 2018 13:27:11 +0000 (UTC), root <NoEMail@home.org> wrote:   >Four year old Samsung 60" UHD QLED tv cannot be repaired. >The problem is lines of dead pixels across screen.   I don't think there's anything wrong with your TV that requires a new LCD panel.   A line of dead (black) pixels is not a "dead pixel". It's a dead row or column device, or more likely, a bad connection or dirty connector between the LCD panel and the row driver device. I've fixed such intermittent connections on computer monitors and laptops by tearing apart the display panel, massaging the ribbon cable connector, and sometimes placing a few layers of tape between the panel sections to compress the connection. This is close:   "Simple most probable fix for Samsung LCD TV black line and were colored lines vertically On screen" <https://www.youtube.com/watch?v=GdaYxdFCi48> Vertical lines are the same as horizontal lines, except on a different connector.   More of the same: https://www.youtube.com/results?search_query=samsung+lcd+horizontal+lines+fix   Your biggest headache will be handling the 60" monster. You'll probably need a large table and possibly a sheet of plywood covered with foam, blankets, or padding. Take photos as you take it apart so that you can remember where things go. Removing the plastic frame is often tricky. There are probably disassembly videos on YouTube.   I've noticed with computer monitors that I see more intermittent connectors when the TV is on a movable hinged wall mount. Any TV that big will tend to flex and twist a little, causing the ribbon cable to move. You might want to tape the ribbon cable to the sheet metal. Most manufacturers do this already, but the tape tends to fall off after a while. Use high temp Kapton tape so that the heat from the panel doesn't melt the glue.   >would cost $1400.   >The tv was top-of-the line 3D 240Hz and cost $3300.   >Is this representative of Samsung?   I don't know. I don't fix Samsung TV's. I have plenty to complain about Samsung computer monitors, but they're still equal or better than most others. Most of the one's I use for myself are Samsung. I have no idea if the replacement panel price is normal. I suspect a big part of the price will be shipping, handling, and transportation to/from the repair shop. Too bad you didn't include the exact Samsung model number so I could check prices.       -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Bruce Esquibel <bje@ripco.com>: Jul 05 10:56AM > Is this representative of Samsung?   Yes.   And LG and Sony and Hisense and TCL and Vizio.   You should look at avsforum.com and check out the threads for any brand.   You'll find in each one multiple complaints about "its only 2,3,4 (pick one) years old and...".   I have a 73" Mitsubishi DLP I can let you have for cheap, they got so bad after mine (with the LaserVue models), they pulled out of the North American market altogether.   Your best bet, if in the states, get a Costco membership and buy the tv there.   They double the warranty, usually you have 2 years in house service, then purchase (usually $89~$99) the squaretrade extention which gives another 3 years.   They won't fix the set (usually) but replace it with something similar.   Simply put, there is no lcd/qled/hdr/3d/edge-lit/fald make or model that you will be giving away to your grandkids no matter how much you pay for it.   After 2 years they are so obsolete (usually surpassed 2 or 3 times) there is no point anymore with repairs. Your $3400 4 year old tv can be replaced with a brand new model for half that now (from Samsung no less).   Only logical move these days is find one you'll fall in love with then get the longest replacement warranty with it.   Or find one you hate (tcl/hisense) and assume you'll be replacing it every 2 or 3 years. Being they are half (or more) cheaper than the mainstream brands, you'll still end up spending the same over the long run.   -bruce bje@ripco.com

Michael <Mikeman400@gmail.com>: Jul 04 03:41PM -0700 On Tuesday, July 3, 2018 at 12:43:13 PM UTC-4, Jeff Liebermann wrote: > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   Everyone thanks for the advice. It is for sure a 48V unit,(batteries were wired as such and it puts out 48v charge current) but the SMPS power supply may have overshot that a bit under load.   My Hakko 936 doesn't quite have enough thermal mass to desolder the FETs (even with the giant chisel tip I put on it) because of the huge double sided traces.   Getting a new hot air rework station this week and that should be able to do the job without cooking the components. I had one before but didnt make it with me on the last move.   Strictly speaking the unit works as a UPS as it is, but I can't use it as an off grid inverter because it won't start off batteries only.   I will check back in after I get the FETs out and check them.

Jeff Liebermann <jeffl@cruzio.com>: Jul 04 06:21PM -0700 On Wed, 4 Jul 2018 15:41:52 -0700 (PDT), Michael   >It is for sure a 48V unit,(batteries were wired as such and >it puts out 48v charge current) but the SMPS power supply >may have overshot that a bit under load.   Look on the top of the first page of the schematic. It says +24v and is connected to the diodes after the AC power transformer. The external battery connectors J5 and J9 traces to a collection of power relays (RY3, RY4) that are labelled as 24V coils. The 4th drawing "Main Circuit BD" also shows +24V. While most of the electronics runs on +12V, I found no evidence of anything labeled +48V. Either the schematic is the wrong unit, there might be a different between "3000" and "SU3000RM", or your batteries were wired incorrectly.   Digging deeper, the SU3000RM uses two 24V RBC11 battery cartridges: <http://www.batteryspec.com/cgi-bin/cart.cgi?action=link&product=152> that are wired like this: <https://www.vps-ups.co.uk/rbc11.html> The connectors go to J5 and J9 which connect the two connectors in parallel for 24V, not 48V.   >Getting a new hot air rework station this week and that should be >able to do the job without cooking the components. I had one before >but didnt make it with me on the last move.   Anything attached to a heat sink is going to be a problem removing with a hot air desoldering station. I suggest a big chisel tip and a solder sucker.   >Strictly speaking the unit works as a UPS as it is, but I can't >use it as an off grid inverter because it won't start off batteries only. >I will check back in after I get the FETs out and check them.   Do you still have the old batteries? If so, can you test the SU3000RM with the batteries installed and see if it survives the initial self test? During this test, the UPS runs on battery for a few seconds. If the batteries are dead, it will so indicate with the front panel lights. It might be a good quick check of the inverter section.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Jul 04 07:20PM -0700 >Can you share details about which parts you used? >What kind of sensitivity can you get? >Thanks, mike   I tried to find the one I built but couldn't. So, I do it from memory.   The "probe" is a wooden coffee stirring rod that I stole from the local coffee shop. Stuck onto the end was a linear Hall effect device in a TO-92 package. As I recall, it was a TI DRV5053: <http://www.ti.com/product/DRV5053> <http://www.ti.com/product/DRV5053/datasheet> <http://www.ti.com/lit/ds/symlink/drv5053.pdf> It comes in several sensitivity ranges. Methinks it was EA or +45 volts/Tesla. That's not very sensitive, but more on that later.   The schematic was very simple. See 8.2.2. on the data sheet or: <http://www.ti.com/product/DRV5053/datasheet/application-and-implementation#SLIS1534512> The output went to crude x1000 LM358 DC amplifier and then to my TEK 2247A scope on the lowest 2mv/div scale.   The reason I threw this together was that I was trying to fix a no-name Chinese solar inverter that had about 32 IGBT devices in parallel in 4 strings. One device was probably shorted, but I couldn't tell by probing. I also couldn't run it long enough to check which device got warm. Checking the gates showed nothing useful. So, my last resort was to try and measure the collector current without breaking any wires. Looking for a switching waveform on the collector would have been so easy, except that some protection circuit turned off the drive oscillator because of the high current. I tried an inductive pickup, but it just picked up junk from the adjacent working devices.   I had just enough exposed collector lead accessible to sense a magnetic field. I had a sample DRV5053 device, so I quickly threw it together on the wooden stick and looked for some indication of a magnetic field. After some tinkering, I could just barely see the current on the scope. Walking it down the line, I found that 3 devices had shorted. I removed the shorted device but did not initially replace them. It worked. I then made a guess as to some potential replacements, actually found some in my pile, and proclaimed the inverter to be repaired (until some better parts arrived in the mail). Note that this repair was done from start to finish in about an hour.   The key here was that it was only going to work with fairly high currents. Judging by my automotive magnetic field ammeter, the inverter was sucking about 30A with the blown devices which was probably distributed as 10A per device. So, how much sensitivity will it take to get a 1 division (2mv) change on the scope? Plugging into a handy Ampere's Law calculator at: <https://getcalc.com/physics-amperes-law-calculator.htm> for 10A at 2mm radius (my guess), I get a 4x10^-8 Tesla field. The Hall effect device has a sensitivity of -90V/T for an output change of a fabulous: 4x10^-8T * 45V/T = 1.8 uV with a gain of x1000, that becomes 1.2mv, which I could just barely see under the noise and garbage on the scope.   So, you're welcome to build such a device, but I don't think it will be a troubleshooters dream current probe, that can measure DC currents without breaking the line. You might want to look into IMC (integrated magnetic concentrator) type Hall effect structures. By grabbing more of the magnetic field and concentrating it into the tiny Hall effect chip area, it produces a higher reading and therefore a higher sensitivity. The problem is that the pickup toroid or core needs to go around the wire, which defeats the basic purpose of the no-contact current probe. However, I suspect that some kind of probe can be contrived with will sense more of the magnetic field than the tiny chip, which will help with the sensitivity problem. "Measuring Current with IMC Hall Effect Technology" <https://www.sensorsmag.com/components/measuring-current-imc-hall-effect-technology>     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

mike <ham789@netzero.net>: Jul 04 10:08PM -0700 On 7/4/2018 7:20 PM, Jeff Liebermann wrote: > tiny chip, which will help with the sensitivity problem. > "Measuring Current with IMC Hall Effect Technology" > <https://www.sensorsmag.com/components/measuring-current-imc-hall-effect-technology>   Thanks, Looks like that's not gonna be worth the trouble for me. Too little sensitivity. I had some success with AC fields using the tiniest torroid core I could find. I cut a slot in the core and wound it full of tiny wire. Took about a dozen tries to cut a slot without breaking the core...good times... In your case, proximity to other strong fields would be an issue.   For stuff that's actually shorted, I've had great success using the HP current tracer and pulser. I can stick the pulse on a trace and tell which direction the current is going. Also useful finding bad caps.

jurb6006@gmail.com: Jul 04 09:34PM -0700 >"When was the last time you saw "it's A Sony!" on a Sony Product? Can't even remember because even Sony knows their products have the quality of cockroach shit. "   Well for me it was 1995 on my SLV-920HF, which still works after greasing that frikken lever that pulls the tape into halfload mode. My SL-HFR60 has never needed services and I now have an old 13" Sony in the bedroom so old it has no letters in the model number, might be a KV-1326 (???) It has better color rendition than I have seen on ANYTHING, except the old KP-36XBR I finally got rid of a few years ago. The pisses me off, there was no room for it. Of course on the 13" I have to turn the color almost all the way down. So it lacks the resolution, but Spock is green and everyone else isn't.   I used to work for a Sony Signature dealer, I touted their products to no end. the only thing was that their audio equipment was totally unimpressive. Seems they have a different idea on how music should sound. But back then everything else was top notch.   Later I took another job and left on good terms, still recommended them and buying them from where I worked before. They had great prices on the high end stuff, and this place had manufacturer's reps begging to get their product on the floor. The owner saw an ad for a Pioneer and told them to come and pick up everything that said Pioneer on it that was in stock or on the floor.   After many more years in servicing them, I found they had become total junk. they wouldn't even put current limiting in their power supplies, something they had done for decades. I never liked their audio equipment and the changes over the years did nothing to endear them to me, to say the least. Anything aftyer the STR-V7 was pretty much junk, and the 7 wasn't all that hefty either, couldn't handle 4 ohms, shit tone controls. Great tuner but I don't need a tuner the size of Kansas. The ESS line, well it is not considered all that great by real audiophiles. Good but not great and their FET amps that destroy themselves if they get low line voltage were not quite what I call good engineering.   Today, I wouldn't hit a dog in the ass with anything they make. And why should I hit a dog in the ass anyway ? Hit the Sony in the ass with a dog. No I guess that doesn't work either.   Everything is junk. Digital TV is junk. Digital FM is junk. New cars are junk.   I watch online shows on my PC(s). I got a 23" monitor in the basement I can actually SEE, and speakers I can actually HEAR. I can pause it for days. And the OS is 17 years old. I got a laptop with possibly the biggest screen of any laptop ever, 17" wide. Both play online video practically flawlessly on second tier DSL. I NEVER reboot the one in the basement, but the laptop I have to every once in a while, maybe once a month if that.   I see a very, very good picture on that 13" right now. the laptop is next to it and it has more resolution that I can't really see, but it is not as good. Nothing will ever beat CRT technology but plasma comes close because it is phosphors. The phosphors are more efficient but they seem lioke the primary colors are contaminated with white. so there needs to be more of a color difference applied for the same saturation level, and its ultimate limit is less than the old inefficient phosphors that yielded that stunning deep blue and green, and even red. My old original XBR projection, the first one, had that. The color depth is nonpareil. And even though the colors in an LCD are separated by prismatic action and pure, they still lack the contrast range, and cannot reproduce like the old style phosphors. The ones with better contrast modulate the light from the LEDs behind to enhance it. You can see the black clipping, and most of them white clip as well. Distortion. thatis not high fidelity rendition, and don't even get me started on that fucking surround sound that makes it impossible to understand the words and you have to crank up the volume to try to hear it and then a car blows up and the neighbors call the cops because they think there was an explosion. And now, you can't even insert an audio compressor inline because it is all digital.   I wouldn't have destroyed the DVD player though, I would sell it on Craigslist to get a few bucks. Get yourself some beer and be happy. Or less unhappy. I am displeased with just about all electronics today and that includes cars. Three [pounds of metal and the rest circuit boards, and if the public REALLY knew how cheap technology is they would burn every car factory in this country to the ground.   Think you had a rant ? Now you KNOW what a rant is, and it is supported by facts.

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