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TV Back-light Spark Gap?
I have a cheapy 19" Philips TV hanging on my office wall.
It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
"Jim Thompson" wrote in message ... I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Likely a dry joint around the HT..... |
TV Back-light Spark Gap?
On 7/19/2012 7:59 AM, Jim Thompson wrote:
I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 07:59:43 -0700, Jim Thompson
wrote: You forgot to include sci.electronics.repair I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Maybe, but I've never seen that happen. There's not enough power in the LCD inverter to draw much of an arc, much less produce a noisy arc. My guess(tm) is that the switching power supply is on its way out. No clue where it's arcing but a charred PCB in the PS Hi-V section would qualify. Open the back, turn OFF the room lights, and look for the sparks. If there's a corresonding change in the picture with every pop, it might be the swithcing power supply. If there's a corresponding change in CCFL backlighting brightness, it might be the LCD inverter. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
TV Back-light Spark Gap?
"Jim Thompson" wrote in message ... I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Turn the swamp cooler down? Cheers |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 09:54:36 -0700, Jeff Liebermann
wrote: On Thu, 19 Jul 2012 07:59:43 -0700, Jim Thompson wrote: You forgot to include sci.electronics.repair I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Maybe, but I've never seen that happen. There's not enough power in the LCD inverter to draw much of an arc, much less produce a noisy arc. My guess(tm) is that the switching power supply is on its way out. No clue where it's arcing but a charred PCB in the PS Hi-V section would qualify. Open the back, turn OFF the room lights, and look for the sparks. If there's a corresonding change in the picture with every pop, it might be the swithcing power supply. If there's a corresponding change in CCFL backlighting brightness, it might be the LCD inverter. Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) Prices are amazing. The 55" flat-screen LCD/LED replacement for this... http://www.analog-innovations.com/SE..._KnockDown.pdf was only $1080 ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
On 7/19/2012 9:45 AM, mike wrote:
On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. |
TV Back-light Spark Gap?
Jim Thompson wrote:
I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Take it apart immediately, remove the backlight power supply and inspect. The classic problem is the long leads sticking out of the back of the board abrade the plastic shield and start sparking to the EMI shield coating on the case. Clipping the leads and replacing the plastic with a piece of Mylar will fix it. I've done a few of these. Jon |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson
wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Prices are amazing. The 55" flat-screen LCD/LED replacement for this... http://www.analog-innovations.com/SE..._KnockDown.pdf was only $1080 I see those at the local recycler all the time. Have your forklift ready. What's interesting is that I also see LCD TV's at the same recycler, which would suggest a rather short lifetime before something blows. The days of 25+ year TV lifetimes are over. These days, you're lucky if the TV can make it through the warranty period before the electrolytics start bulging. This monitor was only 9 months old: http://802.11junk.com/jeffl/pics/repair/slides/LG%20L246WP.html -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
TV Back-light Spark Gap?
"mike" wrote in message ... On 7/19/2012 9:45 AM, mike wrote: On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. I'm betting on a pinched wire. Some Q-dope might be a quick fix. I had a Samsung CRT that would snap every now and then in warmer weather, but never outright failed. Cheers |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 16:39:16 -0400, "Martin Riddle"
wrote: "mike" wrote in message ... On 7/19/2012 9:45 AM, mike wrote: On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. I'm betting on a pinched wire. Some Q-dope might be a quick fix. I had a Samsung CRT that would snap every now and then in warmer weather, but never outright failed. Cheers Do CFL's go that high in voltage? This quits after a few hours of operation ?? ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
"Jim Thompson" wrote in message ... On Thu, 19 Jul 2012 16:39:16 -0400, "Martin Riddle" wrote: "mike" wrote in message ... On 7/19/2012 9:45 AM, mike wrote: On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. I'm betting on a pinched wire. Some Q-dope might be a quick fix. I had a Samsung CRT that would snap every now and then in warmer weather, but never outright failed. Cheers Do CFL's go that high in voltage? ***Circa 1200V to strike the CCFL tube - about half that when ionised. |
TV Back-light Spark Gap?
"Jim Thompson" wrote in message ... On Thu, 19 Jul 2012 16:39:16 -0400, "Martin Riddle" wrote: "mike" wrote in message ... On 7/19/2012 9:45 AM, mike wrote: On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. I'm betting on a pinched wire. Some Q-dope might be a quick fix. I had a Samsung CRT that would snap every now and then in warmer weather, but never outright failed. Cheers Do CFL's go that high in voltage? This quits after a few hours of operation ?? They run somewhere around 1k to 5kv depends upon the cfl. Cheers |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 13:18:00 -0400, "Martin Riddle"
wrote: "Jim Thompson" wrote in message ... I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Turn the swamp cooler down? Cheers Haven't had one of those since 1993. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 12:29:02 -0700, Jeff Liebermann
wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Prices are amazing. The 55" flat-screen LCD/LED replacement for this... http://www.analog-innovations.com/SE..._KnockDown.pdf was only $1080 I see those at the local recycler all the time. Have your forklift ready. I took a power cut-off saw to it and broke it down into pieces I could lift (total weight ~400#). And scavenged all the nice heatsinks ;-) What's interesting is that I also see LCD TV's at the same recycler, which would suggest a rather short lifetime before something blows. Probably the CFL back-light, which is why I went LCD/LED. The days of 25+ year TV lifetimes are over. These days, you're lucky if the TV can make it through the warranty period before the electrolytics start bulging. This monitor was only 9 months old: http://802.11junk.com/jeffl/pics/repair/slides/LG%20L246WP.html ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
"Martin Riddle" wrote in message ... "Jim Thompson" wrote in message ... On Thu, 19 Jul 2012 16:39:16 -0400, "Martin Riddle" wrote: "mike" wrote in message ... On 7/19/2012 9:45 AM, mike wrote: On 7/19/2012 7:59 AM, Jim Thompson wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? ...Jim Thompson Since you didn't mention change in brightness when it pops... First thing I'd try is to plug in headphones and verify it ain't coming out the speaker. Zero cost experiment that might save you a lot of fiddling around. I'd also try the brightness at extremes to see if that changes anything. Weakest link is the transformer. There's often a tiny cap in series with the CFL. I've seen those go open. Might arc across that. Spider webs cause interesting high voltage symptoms. Another thing that happens is that the caps in the low voltage ps go open. The average voltage is the same, but the peak voltage can go much higher. I've only seen that after the fets in the cfl supply short, but I presume that the CFL voltage goes higher before it fails. I'm betting on a pinched wire. Some Q-dope might be a quick fix. I had a Samsung CRT that would snap every now and then in warmer weather, but never outright failed. Cheers Do CFL's go that high in voltage? This quits after a few hours of operation ?? They run somewhere around 1k to 5kv depends upon the cfl. Cheers ****You can get a definitive answer from the HR (famous for their excellent pattern flyback transformers) backlight inverter datasheets, the datasheet I read said 1200V to strike & 600V ionised - if they do a pattern inverter for the specific TV in question, you can nail it to the spot. |
TV Back-light Spark Gap?
On Thu, 19 Jul 2012 17:37:56 -0700, Jim Thompson
wrote: Probably the CFL back-light, which is why I went LCD/LED. Failing CCFL tubes do not create audible arcs. You would also see flashes, dimming, or an orange colored background if it were the tubes or inverter. Since that wasn't mentioned as a symptom, I'll assume that it's not the tubes or inverter. What's the maker and model number of your 19" LCD TV? I'll find you a replacement LCD inverter or some repair clues. However, I still think it's something arcing in the switching power supply possibly inspired by bulging electrolytic caps. 1960's "Save a Tree" 2010's "Save an LCD" -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
TV Back-light Spark Gap?
Jeff Liebermann wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Jim designs integrated circuits. Do you think you can repair them? |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 12:57:32 -0400, "Michael A. Terrell"
wrote: Jeff Liebermann wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Jim designs integrated circuits. Do you think you can repair them? From Jeff's responses I think he has a reading comprehension problem :-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
"Michael A. Terrell" wrote in message m... Jeff Liebermann wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 10:15:00 -0700, Jim Thompson
wrote: Jim designs integrated circuits. Do you think you can repair them? Nope. However, it's possible that he can repair his LCD TV. I just assume that anyone in electronics knows which end of the soldering iron to grab, and how to use a #2 Phillips screwdriver. Tearing apart a 19" LCD TV is easy enough that even and IC designer can do it. From Jeff's responses I think he has a reading comprehension problem My reading is quite comprehensive. Ok, so what did I miss, other than it's a Philips 19" TV and something quits after a few hours? High voltage CCFL inverter arcs http://www.youtube.com/watch?v=cTIEI7lCeQc http://www.youtube.com/watch?v=eyChifmSgH0 http://www.youtube.com/watch?v=MLOBEgm1guU -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
TV Back-light Spark Gap?
Jim Thompson wrote: On Fri, 20 Jul 2012 12:57:32 -0400, "Michael A. Terrell" wrote: Jeff Liebermann wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Jim designs integrated circuits. Do you think you can repair them? From Jeff's responses I think he has a reading comprehension problem :-) No, he just spends too much time on the repair newsgroup. :) |
TV Back-light Spark Gap?
Ian Field wrote: "Michael A. Terrell" wrote in message m... Jeff Liebermann wrote: On Thu, 19 Jul 2012 10:30:08 -0700, Jim Thompson wrote: Maybe I'll just toss it, and buy a bigger TV with LED back-lighting ;-) That would be ecologically incorrect. All you probably need to do to repair your existing TV is open it up, look inside, and see what needs to be replaced or repaired. Plenty of parts available from the equipment cannibals on eBay. Most likely, some bug crawled inside and was fried. Incidentally, next time you design something, try to make it repairable. http://www.ifixit.com/Manifesto/ Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell"
wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
TV Back-light Spark Gap?
Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. Some time ago, to aid in diagnosing a prototype chip, we sent it out to have some wires swapped in the chip. Focused Ion Beam, cost a couple thousand bucks to have one chip rewired. The chip worked after that, so we knew what needed to be fixed in the layout. Jon |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 14:38:17 -0500, Jon Elson
wrote: Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. Some time ago, to aid in diagnosing a prototype chip, we sent it out to have some wires swapped in the chip. Focused Ion Beam, cost a couple thousand bucks to have one chip rewired. The chip worked after that, so we knew what needed to be fixed in the layout. Jon Yep. It's called Ion Beam Milling... add and remove traces. Pretty high resistivity, but usually works for patching and proving CMOS fixes. Then you fix the mask set. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
Jon Elson wrote: Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. Some time ago, to aid in diagnosing a prototype chip, we sent it out to have some wires swapped in the chip. Focused Ion Beam, cost a couple thousand bucks to have one chip rewired. The chip worked after that, so we knew what needed to be fixed in the layout. Not something you would do in the typical repair shop, and it wouldn't help with a cratered chip. :) |
TV Back-light Spark Gap?
Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 18:41:05 -0400, "Michael A. Terrell"
wrote: Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. That's a good portion of my work... cutting costs in _very_ high volume consumer goods... or things aimed at those consumers, like billboard electronics. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 18:40:32 -0400, "Michael A. Terrell"
wrote: Jon Elson wrote: Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. Some time ago, to aid in diagnosing a prototype chip, we sent it out to have some wires swapped in the chip. Focused Ion Beam, cost a couple thousand bucks to have one chip rewired. The chip worked after that, so we knew what needed to be fixed in the layout. Not something you would do in the typical repair shop, and it wouldn't help with a cratered chip. :) You missed the "couple thousand bucks". Ion Milling is only done during development of chips. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
TV Back-light Spark Gap?
"Jim Thompson" wrote in
message ... I doubt many of the engineers here design consumer electronics. ^^^^ That's a good portion of my work... cutting costs in _very_ high volume consumer goods... or things aimed at those consumers, like billboard electronics. Ever-self-important Jim Thompson, naturally, counts himself thousands of times over on a simple question. Sadly, he's not great at statistics... FWIW, right now I'm working on industrial electronics. Not really consumer, much smaller quantities. Statistically, I predict a power law: 10% of the engineers here account for 90% of the productivity of all engineers here, measured as total number of parts produced. Meanwhile, 10% of the engineers are connected to 90% of all products (by diversity, including myriad low quantity projects). Some engineers will be well represented by large numbers of small projects, as well as a small number of very large projects; Jeorg and Hobbs are probably nicely representative of this subset. Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms |
TV Back-light Spark Gap?
Jim Thompson wrote: On Fri, 20 Jul 2012 18:40:32 -0400, "Michael A. Terrell" wrote: Jon Elson wrote: Jim designs integrated circuits. Do you think you can repair them? ***Once or twice I've chipped back the encapsulation to repair a snapped off pin. You patched the package, not the IC itself. Some time ago, to aid in diagnosing a prototype chip, we sent it out to have some wires swapped in the chip. Focused Ion Beam, cost a couple thousand bucks to have one chip rewired. The chip worked after that, so we knew what needed to be fixed in the layout. Not something you would do in the typical repair shop, and it wouldn't help with a cratered chip. :) You missed the "couple thousand bucks". Ion Milling is only done during development of chips. No, I saw it. That was the main reason you won't find it in a repair shop. The other is that you wouldn't be able to train them how to use the equyuipment. :( |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 18:41:05 -0400, "Michael A. Terrell"
wrote: Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. Yep. Much of that has been exported to China. Kinda depressing. Here's the list of American TV manufacturers: http://www.americansworking.com/tvs.html -- # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060 # 831-336-2558 # http://802.11junk.com # http://www.LearnByDestroying.com AE6KS |
TV Back-light Spark Gap?
Jeff Liebermann wrote: On Fri, 20 Jul 2012 18:41:05 -0400, "Michael A. Terrell" wrote: Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. Yep. Much of that has been exported to China. Kinda depressing. Here's the list of American TV manufacturers: http://www.americansworking.com/tvs.html I doubt if I'll be buying any more new TVs I have about six working TVs at the moment, and gave away another half dozen a couple years ago. I also have TV tuner cards for several computers. |
TV Back-light Spark Gap?
On Fri, 20 Jul 2012 19:01:16 -0700, the renowned Jeff Liebermann
wrote: On Fri, 20 Jul 2012 18:41:05 -0400, "Michael A. Terrell" wrote: Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. Yep. Much of that has been exported to China. Kinda depressing. Here's the list of American TV manufacturers: http://www.americansworking.com/tvs.html That used to be common in the communist and probably still is in 3rd world countries where tariffs and other barriers are high- a manufacturer would ship CKD or SKD 'kits' to the target market and the final assembly would take place. Of course the cost was higher, the quality usually also much lower than the originals, but there were some jobs for locals created. This looks like pretty much the same thing- it definitely does not meet the standard for "Made" in USA. But they can print big flags on the boxes. "The components will still be made in China for now, with the hope that in time they too will be made in America." I'd be willing to bet that "components" include fully populated and tested PCBs, wire harnesses and such like. It's a bit sad. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com |
TV Back-light Spark Gap?
Spehro Pefhany wrote: On Fri, 20 Jul 2012 19:01:16 -0700, the renowned Jeff Liebermann wrote: On Fri, 20 Jul 2012 18:41:05 -0400, "Michael A. Terrell" wrote: Jeff Liebermann wrote: On Fri, 20 Jul 2012 14:32:50 -0400, "Michael A. Terrell" wrote: No, he just spends too much time on the repair newsgroup. :) True. The problem is that there currently aren't many interesting repair related topics in the repair newsgroups. So, I thought I would come over to the design group, where the problems are created. If I can't be part of the solution, I might as well become part of the problem. I doubt many of the engineers here design consumer electronics. Yep. Much of that has been exported to China. Kinda depressing. Here's the list of American TV manufacturers: http://www.americansworking.com/tvs.html That used to be common in the communist and probably still is in 3rd world countries where tariffs and other barriers are high- a manufacturer would ship CKD or SKD 'kits' to the target market and the final assembly would take place. Of course the cost was higher, the quality usually also much lower than the originals, but there were some jobs for locals created. This looks like pretty much the same thing- it definitely does not meet the standard for "Made" in USA. But they can print big flags on the boxes. "The components will still be made in China for now, with the hope that in time they too will be made in America." I'd be willing to bet that "components" include fully populated and tested PCBs, wire harnesses and such like. It's a bit sad. I have freinds who custom manufacture canopies for art shows. They can get all but one component made in the US. The heavy vinyl they use hasn't been made in the US for over a decade. They are constantly looking for a US source, with no luck. All of the assembly, from raw aluminum to finished product is US made, otherwise. Because of that, they can't claim to be a US made product. |
TV Back-light Spark Gap?
On 2012-07-21, Spehro Pefhany wrote:
That used to be common in the communist and probably still is in 3rd world countries where tariffs and other barriers are high- a manufacturer would ship CKD or SKD 'kits' to the target market and the final assembly would take place. Of course the cost was higher, the quality usually also much lower than the originals, but there were some jobs for locals created. AIUI removing the steering wheel is enough for a car to be imported to Australia as "parts" This looks like pretty much the same thing- it definitely does not meet the standard for "Made" in USA. But they can print big flags on the boxes. "The components will still be made in China for now, with the hope that in time they too will be made in America." I'd be willing to bet that "components" include fully populated and tested PCBs, wire harnesses and such like. It's a bit sad. Now that there's a market for those components there's atleast a posibility that someone can manufacture some components locally. -- š‚šƒ 100% natural --- Posted via news://freenews.netfront.net/ - Complaints to --- |
TV Back-light Spark Gap?
On 21 Jul 2012 07:11:31 GMT, Jasen Betts wrote:
On 2012-07-21, Spehro Pefhany wrote: That used to be common in the communist and probably still is in 3rd world countries where tariffs and other barriers are high- a manufacturer would ship CKD or SKD 'kits' to the target market and the final assembly would take place. Of course the cost was higher, the quality usually also much lower than the originals, but there were some jobs for locals created. AIUI removing the steering wheel is enough for a car to be imported to Australia as "parts" It must be scary to drive there, with some fraction of the motorists driving around without steering wheels. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators |
TV Back-light Spark Gap?
"John Larkin" wrote in message ... On 21 Jul 2012 07:11:31 GMT, Jasen Betts wrote: On 2012-07-21, Spehro Pefhany wrote: That used to be common in the communist and probably still is in 3rd world countries where tariffs and other barriers are high- a manufacturer would ship CKD or SKD 'kits' to the target market and the final assembly would take place. Of course the cost was higher, the quality usually also much lower than the originals, but there were some jobs for locals created. AIUI removing the steering wheel is enough for a car to be imported to Australia as "parts" It must be scary to drive there, with some fraction of the motorists driving around without steering wheels. ***They fit those tiny racing steering wheels - so the escaped convicts can drive with handcuffs on. |
TV Back-light Spark Gap? Update.
On Thu, 19 Jul 2012 07:59:43 -0700, Jim Thompson
wrote: I have a cheapy 19" Philips TV hanging on my office wall. It's taken to making a popping noise, suspiciously sounding like a spark gap. I'm pretty sure this is CFL back-lit. Anyone knowledgeable of what to do about this... adjustment to look for, etc ? Update: While on a phone call I noted that the muted TV has no pop, and the screen never did "blink", so the popping noise must have another cause. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. |
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