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Micky <NONONObobbyburns1111@gmail.com>: Jul 16 03:09PM -0400 On Fri, 15 Jul 2016 10:44:17 -0700 (PDT), mail4ronald17@gmail.com wrote:   >I have got a Sony Wega Flat CRT TV – KV-AR21M83. One day its picture gone bad. Before this it never gave problem. Its picture started to give disturbance, coloration problem, colour bleeding and also sometimes gave noise. So, I stopped using the TV but occasionally I switched it on to see its situation. I called a technician from Sony but he told that he does not know that where the fault is and I'll have to take it to service centre but I did not take it. One day I again switched it on but suddenly the disturbance increased. So I got frightened and turned it off. When I again switched it on the TV started to operate normally. But another problem came up. Whenever I switched on the TV and before the picture came on the screen, the TV displayed a green colour glow and also green coloured horizontal lines on the screen appeared for about 2 seconds and then vanished. The lines were not completely perpendicular. The lines were somewhat slanting, raised from the right side. The picture   I presume those are raster return lines, that would be blanked out if things were working normally. The electron beam goes from one side to the other illuminating the screen, but then it has to get back to the first side without adding unwanted light to the picture. I never did understand why the slope was more than two lines hight at the high end, however.   >itself was fine but maybe with somewhat reduced colour accuracy. I felt it so. I could be wrong. Anyways, I used the TV for 1 - 2 months and then closed and covered it as I was using another TV.   >After few months, I needed to use this TV again. So I switched it on. But the TV did not switch on. This was very much unexpected. Only the LED light on the TV blinks 8 times in red. I searched to see that do these blinks indicate something. I found out that 8 blinks as in my case indicates problem with audio IC IC406. But there was no audio problem in this TV. Only picture had issues.   >So, what exactly has gone wrong in the TV?   Hold the TV closer to your computer so I can figure that out.   > Is it the same component which is responsible for TV not switching on and the earlier picture problems?   Maybe.   >I hope that nothing has happened to the picture tube as it is not replaceable.   When there is no picture, most of the people I dealt with assumed the problem was the picture tube, and it never was. Old bad picture tubes on black and white TVs have a silvery appearance, but I don't know how to describe the same problem on color tvs. But it's not what you've described.

Tim R <timothy42b@aol.com>: Jul 18 05:30AM -0700 On Saturday, July 16, 2016 at 7:25:43 AM UTC-4, Bruce Esquibel wrote:   > The only money I'd put into it is paying someone to haul it away.   > -bruce > bje@ripco.com   And that's no longer simple. The trash pickup won't take it, and it now costs $25 per unit in my area to dispose of.

"pfjw@aol.com" <pfjw@aol.com>: Jul 18 06:12AM -0700 On Monday, July 18, 2016 at 8:30:52 AM UTC-4, Tim R wrote:   > > -bruce > > bje@ripco.com   > And that's no longer simple. The trash pickup won't take it, and it now costs $25 per unit in my area to dispose of.   Around here, Best Buy takes everything - no cost. The Township takes electronics four times per year, but one must be a township resident.   We have a very large Sony WEGA that followed us back from Saudi in 2005 (purchased in 2002), that has given us no trouble whatsoever. Interesting set, smart tuner, smart power-supply, almost nothing inside other than a (rather small) circuit board and the CRT, and a rather decent picture.   Peter Wieck Melrose Park, PA

mail4ronald17@gmail.com: Jul 18 07:59AM -0700 > In Sonys of that vintage they has alot of problems wit the CRTs. Usually the green for some reason. The gun gets weak and then shorts sometimes.   > The AKB keeps the greyscale right until the green gun is too weak to do so. Then it is overdriven. This happens sometimes without notice.   Thanks but what is AKB?   > The codes are not all that good. IF the main power supply is blown and it sees no voltage at the supply to the audio IC and thinks it is shorted. Like some cars, you read the codes ad they do not tell the whole story. You have to look over all the codes it actually has. In the US they standardised it, but not on TVs. But before that you had to interpret them by the model. And ironically if you got a code (even today) that says too lean alot of people think fuel filter or dirty injectors, but it really needs an O2 (lambda) sensor and is actually running too rich.   > You actually could have a bad audio IC, you said it made a noise. But with the green on the screen with the (retrace) lines I suspect the CRT very greatly. The audio IC has nothing to do with the color.     Maybe but that noise was due to picture disturbance. Yes, I think these codes do not always give the correct indication of fault or these codes have got even more meaning which is not given in the code paper.     > If you really like CRT TVs, find a Toshiba somewhere. If the CRT is good after all these years it will probably be good for quite some time. Actually if you find a Sony from the 1980s that still looks good it might last a while.   Is Toshiba still manufacturing CRT TV?

mail4ronald17@gmail.com: Jul 18 08:18AM -0700 On Sunday, July 17, 2016 at 12:40:01 AM UTC+5:30, Micky wrote: > the first side without adding unwanted light to the picture. I > never did understand why the slope was more than two lines hight at > the high end, however.   Yes, it seems raster line. I have heard about them but don't understand them well. It looked like some filament in picture tube is glowing in green colour.

jimenezriquelmej@gmail.com: Jul 18 08:10AM -0700 quiero comprar placa lj41-05779a muy importante revision R2.O no me vale revision R2.12.GRACIAS .dime precio con tansporte.

JC <Chipbee40_SpamNo@yahoo.com>: Jul 18 08:39AM -0400 On 7/17/2016 11:08 PM, Phil Allison wrote:   > A 4Hz sine wave with the same peak value is then required.   > ... Phil   thanks Phil, I'll try it.

JC <Chipbee40_SpamNo@yahoo.com>: Jul 18 08:39AM -0400 On 7/18/2016 12:10 AM, Black Iccy wrote:   > Base Mod by Mod freq (rate) > 3Khz +/- 'x'Hz @ rate 'y' > 3000 30 4   Thanks. Will try it.

Stormin Mormon <cayoung61@hotmail.com>: Jul 18 07:04AM -0400 On 7/17/2016 8:47 PM, Danny D. wrote: > ----- > 4. Long > 5. Ago   Your answer is irrelevant to my question.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"pfjw@aol.com" <pfjw@aol.com>: Jul 18 05:21AM -0700 This horse is long dead, flayed and flensed.   Please stop trying to feeding it.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Jul 17 01:10PM -0700 On Sun, 17 Jul 2016 18:48:38 -0000 (UTC), Cursitor Doom   >I wouldn't have minded so much, but a while ago we had a thread on the >golden rules of troubleshooting and my contribution was, of all things, >"assume nothing" (!)   Nice. The problem is that the common adage "assume nothing" should really be "conclude nothing". My methods do quite a bit of assuming. For example, I assume that recurring problems will tend to reoccur. I assume that a manufacturer that makes crap, will continue to make crap. I assume that companies that make marginal products will continue to make marginal products. I assume that bad work habits will persist for a lifetime. In repair, I assume that the gizmo in question actually worked at one time (assuming it was not shipped dead on arrival). Lots of assumption, most of which are not totally true 100% of the time, but are a good start.   Where we all get into trouble is when we can't distinguish between working assumptions and a logical conclusion. Working assumption are generalizations, which may help narrow down the cause of a problem, but not necessarily point directly at the cause of a problem. Logical conclusions are when we take observations, measurements, and maybe a troubleshooting flow chart, and produce a possible culprit. The first (assumption) helps us find the problem. The 2nd (premature conclusion) usually distracts us in other directions.   So, you have my permission to make as many assumptions as you feel necessary to simplify a problem, but not to draw any conclusions from those assumptions.   >so I don't do these sort of things on a daily basis. Consequently my >reasoning skills are nowhere near as strong and well-developed as someone >who's fully immersed in the business.   It's neither an art or a science. It's a mixture. One cannot troubleshoot any problem solely on the basis of science or logic. What I think works best (for me) is an understanding of how the circuit works or should work. From that, I can guess what I should see in voltages and waveforms. Knowing what the circuit should NOT be doing is as important as what it is expect to do. That will usually reduce the problem down to the sub-section. To isolate it down to the component is where art is best. Use of a heat gun, cold spray, external signal source, self-heating, and just the look of a component, are all things that are not particularly well defined, and therefore more of an art. When both science and art fail, I try psychology. What was the designer or manufacturer trying to accomplish? I'm often amazed at how clear things become when I think about the designers motivation, instead of what is facing me on the bench.   My apologies for not being able to provide a clear and defensible picture of how troubleshooting works. It's still much of a puzzle to me. Sufficient to say that one starts with the science, which yields the fundamental functions of the circuit. One then goes to the art, where experience is more important. One then goes to psychology, where second guessing the designer provides some possible answers.   If such philosophical issues are of interest, I suggest you get a copy of Outliers by Malcolm Gladwell. Cheap enough used: <https://en.wikipedia.org/wiki/Outliers_(book)> <http://www.alibris.com/search/books/isbn/9780316017923> "Throughout the publication, Gladwell repeatedly mentions the "10,000-Hour Rule", claiming that the key to achieving world class expertise in any skill, is, to a large extent, a matter of practicing the correct way, for a total of around 10,000 hours." 10K hrs is about 5 years of total immersion. I've found this to be true for most everything I've tried, except my crappy piano playing. Well over 10K hrs of practice does not compensate for a fundamental lack of talent.     -- 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

Cursitor Doom <curd@notformail.com>: Jul 17 10:09PM On Sun, 17 Jul 2016 13:10:53 -0700, Jeff Liebermann wrote:   > for most everything I've tried, except my crappy piano playing. Well > over 10K hrs of practice does not compensate for a fundamental lack of > talent.   Tell me about it! Having a natural gift for such activities makes a massive difference. BTW and FWIW, there's a very interesting discourse on the correct approach to troubleshooting in Robert Persig's Zen and the Art of Motorcycle Maintenance. And it's not restricted merely to motorcycles, either:   https://www.amazon.com/Zen-Art-Motorcycle-Maintenance-Inquiry/ dp/0060589469/ref=sr_1_1?ie=UTF8&qid=1468793289&sr=8-1&keywords=zen+and +the+art+of

Phil Allison <pallison49@gmail.com>: Jul 16 09:23PM -0700 > These days I apply it with a syringe right to the contacts. > If the blades are really dusty I use stuff that is completely residue free, > and I DO test it.   ** By "contacts" you mean the bronze bearings and fingers that ground the moving plates ?   A few drops of WD40 or similar works like magic and restores normal operation to AM and FM bands.   BTW:   Audio Generators often use a tuning gangs, not just old tube models but also modern examples with FET input sustaining amplifier circuits. The dual gangs used are the same as found in tube AM radios and give the advantages of infinite resolution and indefinite life compared to using a dual pot.   The circuit used is a Wien Bridge and to get down to 20Hz means using 20Mohm resistors in the network ( f = 1/2piRC ). The whole gang has to be isolated from ground since the two sections are connected in series.     .... Phil

Ralph Mowery <rmowery28146@earthlink.net>: Jul 11 03:19PM -0400 I have not used it but just bought a spray can of Deoxit. From reading about it, it seems to be the greatest stuff for cleaning contacts.   I have an old Tectronix Scope 465B that one chanel has a flakey input switch. The manual says only to use isopropal alcohol to clean it with, I did that with some 99% and it helped some, but thinking of using some of the Deoxit on the switch. Would that be ok or not.   I would hate to mess up the switches as they would be almost impossiable to find replacements for .

Ralph Mowery <rmowery28146@earthlink.net>: Jul 11 08:25PM -0400 In article <4fdd5d-fvu.ln1@coop.radagast.org>, dplatt@coop.radagast.org says... > problem, other than an actual repair of the switch (replace the > contact fingers) and as you note, this may not be possible due to lack > of available parts.   Usually it is best to stay with what the manufacturer recommends, but in this case the Deoxit was probably thought of years after the scope was made.   Thanks for the advice of the Deoxit Gold. Maybe I will try that at some point instead of the kind I have.   As stated above I have been repairing some electronics over the last 40 years as a hobby and never tried the Deoxit. As all reports seem to say this stuff cures anything that WD 40 won't.. ( I never use WD 40 by the way for various reasons.)   It has been a while from the last time I looked in the scope, but best I remember that while the part you turn is a rotary switch, the contacts are actually slide switches of sorts. Then as it was mentioned it may attack the plastic. Some cleaners do and some don't. I used to use LPS cleaner and never found plastic that it would affect.

Ralph Mowery <rmowery28146@earthlink.net>: Jul 11 11:40PM -0400 In article <f0d57e1f-3bb5-4750-8010-ba75c696de20@googlegroups.com>, pallison49@gmail.com says...   > There are many similar products too, like CRC2-26 that have the same formulation and so do exactly the same job while costing more.   > What the heck do you use ?   > .... Phil   Depends on what I am doing. Where many would use WD40 as a cleaner, I use Kroil as a penetrating type of oil and a few other usages.   For some cleaning of the grease off large pieces of metal I use Ed's Red.

Ralph Mowery <rmowery28146@earthlink.net>: Jul 12 06:05PM -0400 In article <565f57e6-3068-40bc-88c1-1fe63d4bc50c@googlegroups.com>, dansabrservices@yahoo.com says...   > The MSDS should list all of the chemical ingredients. Check there.   Not exectally. It lists something called Deoxit D-Series D100L Trade Secret for the CAS No.   That tells nothing about what the C100L is.   http://hosatech.com/wp-content/uploads/2013/11/MSDS-E-D5S-A_v31.pdf

Ralph Mowery <rmowery28146@earthlink.net>: Jul 12 12:44PM -0400 In article <me4aoblk09e4q0h1r6aff0sbdi451fa0jn@4ax.com>, jeffl@cruzio.com says... > because the oleic acid will attack copper and therefore must be washed > off by something after its used to clean the oxides, sulphides, crud, > dirt, tar, and oils off the contacts.   The Deoxit I bought a few days ago must not contain any of the oleic acid. Not mentioned on the can. This is Deoxit D5. The can says it protects surfaces so doubt this is a copper eating compound.   The directions say to spray and activate the knobs. Then give it a short spray and wait 2 minutes before turning the equipment on. I guess that the wait time is to make sure any thaing that burns has evaporated. There is no mention of cleaning it off, but really should be left on the contacts from the way I read it.

Ralph Mowery <rmowery28146@earthlink.net>: Jul 12 04:51PM -0400 In article <chdaobhitefakvmkjulk58bhhvkau9tkrm@4ax.com>, jeffl@cruzio.com says... > >contacts from the way I read it.   > Find a piece of copper. Drip on some Deoxit. See if there's any > green colored corrosion. You may need a microscope to see it.   They do not list the % on the can I have,but that is what is in it on the lable for the can I just bought.   I sprayed some on a piece of copper PC board so will wait overnight and see if it turns green.   I wish the government would make the companies list everything the put into the products. Not being able to hold back as far as a trade secret. I don't care what percent, but do care about what is in it.

jurb6006@gmail.com: Jul 17 12:58PM -0700 >"** By "contacts" you mean the bronze bearings and fingers that >ground the moving plates ? "   Exactly. If the plates are clean that is all it needs and usually the alignment stays put enough that you only have to hit the trimmer caps a little bit to tweak it.   And realizing that when you clean a pot you are cleaning the contact to the wiper which is in the center, not the carbon element, I have successfully use LPS2 from the front. It gets through and takes care of it.   It is surprising how long it took for these tuning caps to become in need of cleaning. Back in the 1970s it was unheard of. Even now, alot of people who still have analog tuners just leave them on one station so they never move. Pots also, move them around all the time and they clean themselves.   Of course eventually there will be no such things, just buttons. Oh and rotary encoders. I have a bad problem with those but I am not going to ask you because you are in bumfukt Egypt or whatever. I need to source them here and not for twenty bucks apiece. They are not optical either. And I am serious unsure of how any I will need. I got 53 units and figure by cannibalisation probably get 35 or so of them up and saleable. These things, when the rotary encoder starts going the SOB will go down when you turn it up, up when you turn it down. That can be annoying and I don't want to see these things coming back with bullet holes in them.

Amanda Riphnykhazova <licensedtoquill@gmail.com>: Jul 17 07:53AM -0700 > -- > Best Regards: > Baron.   But it is exceptionally unwieldy and heavy!

ajgboomer@gmail.com: Jul 17 07:11AM -0700 The following link is a rough schematic of the 12V 6A-2A / 6V charger: https://photos.google.com/search/_tra_/photo/AF1QipNXWaVaaAFuiiNUne5LutYuxNwdPGT03vcmpefG   Please note: All resistor values are measured and approximate! Theory of Operation: The input transformer has some primary side switching to change the secondary voltage for 12V 2a, 6a and 6V. SCR's AC1 and AC2 are triggered on alternate half cycles of the ac input to charge the battery. Triggering is done by P1 turning on via N1 turning on, N2 and P2 turning off. The voltage divider of 23K and the parallel 9.4k resistors sets VREF as a percentage of battery voltage. The TL431 has a nominal reference level of 2.495 volts. Therefore, V_BATTERY must be > 2.495/(4.7/(23+4.7)) or about 14.7 volts to turn on VR which disables charging by turning on P2 - N2 turning off N1,P1, AC1, AC2. P3 provides hysteresis to hold VR conducting by raising VREF when VR turns on. P4 turns on when P1 is on and V_BATTERY exceeds the rectified AC from D1 D2 via P1. P4 on turns on N3 which clamps VREF low turning VR off and continuing to enable triggering. The sensing process repeats on each AC half cycle. AC1 and AC2 will turn off at the end of their positive cycle if there is no gate drive from P1. Design Notes: V_BATTERY is required to power N1,N2,P2,VR,P3,N3. Without battery voltage, N1 will not conduct and P1 will not trigger AC1 and AC2 => No battery charging. The reference voltage divider is fixed for a 12 Volt lead acid battery. Hence the note on the charger stating that 6Volt battery charging must be manually terminated. N2, N3 have no base emitter bypass resistors. Collector - base leakage current could turn them on. There is no protection for reversing the battery leads. It May be OK as is but I have not tried it. Possible failure modes: AC1 and/or AC2. would be likely candidates. BT151's are about $0.75 each in low quantities. AC1/AC2 triggering problems require chasing through the entire PC board to see where the signal is lost.   Overall, the HF unit is well constructed for the price. I could envision scenarios where it would fail. YMMV ;-)   AJG

Micky <NONONObobbyburns1111@gmail.com>: Jul 16 03:02PM -0400 >and now it all works fine again. So, should I start shopping for a >video card too? Could the flaky power supply be affecting the video >card too?   You're assuming that the time in fridge is what made it work when on other occasions waiting itself had an effect.   Anyhow, I once got 3 moderately old video cards for 10, inc. shipping, probably on ebay. Each failed after about 3 years but I'd rather start with a spare old card than buy a fancy one not being sure it's the problem. You could also try plugging in another monitor when yours isn't working.   I don't really think the PSU is affecting the picture, but you do have a point that getting another video card would narrow things down. So will the new ps when it comes.   BTW, paragraphs would make your post much more legible.

etpm@whidbey.com: Jul 16 02:56PM -0700 On Sat, 16 Jul 2016 15:02:01 -0400, Micky >will the new ps when it comes.   >BTW, paragraphs would make your post much more legible. >>Eric OK, I'll try paragraphs.   I am not assuming that the fridge treatment made the card work, but I think it may have. I just knew that it took some time being off for it to work again and I didn't know if cooling might have made it work again. I wrote what I did trying to be thorough.     Eric

Micky <NONONObobbyburns1111@gmail.com>: Jul 17 07:23AM -0400 >think it may have. I just knew that it took some time being off for it >to work again and I didn't know if cooling might have made it work >again. I wrote what I did trying to be thorough.   That's a good practice. Better than medium, and far better than the opposite where people leave even important things out.

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