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Archer <iam@here.com.invalid>: Nov 22 08:31PM +0530 Hi Friends   I have a Samsung Lappy Modl R439. When I press the start button the blue indicator near the button comes on but the lappy does not start.   Wait in this condition for about 10 minuts (blue indicator on). Then press the button so the blue indicator goes off. Now when I press the start button the lappy starts.   The battery is new and fully charged.   What could be the reason? TIA for any suggestions.   -- Sandy

Ralph Mowery <rmowery28146@earthlink.net>: Nov 22 10:59AM -0500 In article <l0n83c5fn8hurp94v23kaekn9894b286e8@4ax.com>, iam@here.com.invalid says... > start button the lappy starts.   > The battery is new and fully charged.   > What could be the reason? TIA for any suggestions.   Probably bad capacitors on the mommy board.

N_Cook <diverse@tcp.co.uk>: Nov 22 04:14PM On 22/11/2016 15:01, Archer wrote: > start button the lappy starts.   > The battery is new and fully charged.   > What could be the reason? TIA for any suggestions.   Report back the timings/consequence if you do the following Put it in a fridge for 1/2 hour before starting up procedure Put over a room radiator 1/2 hour,before starting up

Robert Bannon <rbannon@yahoo.spam.nowhere.invalid>: Nov 22 12:21AM On Mon, 21 Nov 2016 11:17:06 -0800 (PST), Cindy Hamilton wrote:   > Ok, but I still don't understand why you're adamant about doing the > solvent phase indoors. Is it too cold out where you live?   What are most household chemicals? They're just *diluted* versions of chemicals. Right?   For example, what's household bleach? It's just diluted bleach.   What is nail polish remover? It's just pretty smelling diluted acetone or ethyl acetate.   What is rubbing alcohol? It's just vastly diluted isopropyl alcohol.   Why not just use the concentrate? Concentrated pool bleach is what I use in my washing machine. Concentrated muriatic acid is what I use in my toilet bowl. Pure acetone is what my kids use for removing nail polish.   So, currently, I use the "concentrated" goo remover outside, which works fine as gasoline melts virtually all food jar label goop, and what gasoline doesn't melt, the acetone generally does.   While I use most of my chemicals in the concentrated form, gasoline stinks and is flammable so I want to simply dilute the gasoline so that it (a) doesn't stink as much and so that it (b) isn't as flammable.   If that were easy to do, I never would have asked. BTW, I'm sure it's doable - simply because I can dilute with petroleum distiallates. I just don't happen to have cans of petroleum distillates lying around.   I suspect the gasoline works almost as well at 1/10th its original concentration, as gasoline is just petroleum distillates anyway, which is what most "spirits" are.

Wayne Chirnside <faux@notthere.com>: Nov 22 12:16PM On Tue, 22 Nov 2016 00:21:07 +0000, Robert Bannon wrote:     > I suspect the gasoline works almost as well at 1/10th its original > concentration, as gasoline is just petroleum distillates anyway, which > is what most "spirits" are.   Mineral oil works for me for many types of goop - adhesive.

"pfjw@aol.com" <pfjw@aol.com>: Nov 22 07:29AM -0800 On Saturday, November 19, 2016 at 8:19:45 PM UTC-5, Charles Bishop wrote:   > The thread has 84 responses, some of which ignore your question to > advise you on safety.   Sure. As the OP is a candidate for a Darwin Award either from self-immolation or the breathing of toxic fumes leading to cancer or similar, and as "real men" are scarce on the ground, we were all concerned.   I have found that very hot water first, then a bit of vegetable oil rubbed in with the back of a knife gets about any label off of about any glass jar with only a bit of effort. I cannot even fathom why anyone would use gasoline inside or out for this purpose. Shrink-wrap plastic labels are a bit of a challenge, but in these cases, a single-edge razor or carpet knife does a fine job of removing the label, leaving only a small amount of adhesive. Then the hot water and vegetable oil for that.   But a benzene based solvent? YIKES!   http://www.cancer.org/cancer/cancercauses/othercarcinogens/intheworkplace/benzene

N_Cook <diverse@tcp.co.uk>: Nov 22 02:58PM On 03/11/2016 09:46, N_Cook wrote: > R channels with original preset setting. Will add 8R loads and repeat > these tests and adjust bias while still at 60% mains ,interim, before > going up to 100% mains   Required 6 diodes of the SM" 2 in 1 pack BAT54S type I used, not 5, to get the right bias zone for the preset, 100% mains and stable wiht load, just quality of sound check to go

Jeff Liebermann <jeffl@cruzio.com>: Nov 21 08:37AM -0800 On Sun, 20 Nov 2016 22:29:35 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >I can't tell from here where the noise is coming from. Usually, I put >a small loop antenna on my spectrum analyzer and save it around the >power supply while under load. That usually locates the general area.   Is this the one or is there some reason you didn't bother disclosing the model number? Notice that the SEC-1235 is a 12V 30A device and current limits at 35A. How many amps are you drawing? <http://www.samlexamerica.com/products/ProductDetail.aspx?pid=66>   See page 10 for RFI information: <http://www.samlexamerica.com/documents/manuals/11001-SEC-1235-1235M-1114.pdf>   -- 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>: Nov 21 10:07AM -0800 >are higher value types, say those beyond 330uf or so. >Smaller electros fail at the same rate of their big >brothers but don't generally visually vent.   I know the feeling: <http://802.11junk.com/jeffl/pics/repair/slides/bad-caps.html> That's about a 5 month collection, mostly from motherboards, power supplies, and LCD monitors. I've cut back on the component level repairs in the last year, so this years collection is about 1/3 the size. I have 4 different ESR testers and use them often.   >In the old days, capacitors didn't bulge unless they were >tortured. Today it's mediocre chemistry that causes this, >not circuit issues.   In the bad old daze, the electrolytics were running at 60Hz, not 60KHz. The power (heat) dissipated in the electrolytics is a function of frequency.   >If you were to take apart 10 working flat screen TVs made >in the last few years, half of them would show some sign of >bulged or top vented capacitors despite running normally.   Ok, time to vent...   I blame CAD (computer aided design) for the problem. CAD has allowed designers to accurately predict the life of some components including electrolytics. If the operating parameters are known (voltage, temp, ripple current, starting ESR, etc), the lifetime can be calculated. Having a component last longer than the warranty period is considered wasteful by many manufacturers. Therefore, they select the cheapest possible part that will work up to when the warranty expires but no longer. The result is a product where every component blows up at the same time, just after the warranty expires. The 10 flat screens in your example will not show one bad component. Instead, there will be dozens, all different brands and values. This is not due to crappy manufacturing, but rather due to careful selection for the MINIMUM lifetime of the component.   -- 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

"pfjw@aol.com" <pfjw@aol.com>: Nov 21 10:34AM -0800 On Monday, November 21, 2016 at 1:07:20 PM UTC-5, Jeff Liebermann wrote: > dozens, all different brands and values. This is not due to crappy > manufacturing, but rather due to careful selection for the MINIMUM > lifetime of the component.     I would refine this somewhat. When this happens, the average consumer will change brands as most (well, not the typical Trump supporter) recognize that something failing just after the warranty period is the manufacturer wanting to maintain the demand stream. I have found that such electronics - based on average hours used and other factors - tent to last about 25% beyond the warranty period - that is, if they last the first six weeks. Just long enough for the consumer to forget the warranty period.   There are exceptions: We have a Sony CRT-type TV purchased in Saudi in 2002 that has probably 13,000 hours on it that has survived two moves, two ocean voyages, kids, cats, dogs and such without a hitch. The Panasonic Plasma with about 6,000 hours on it is doing fine (so far) as well. Frigidaire refrigerators have about 5 years + one month before they crap out. GE units of US origin (in our experience) are pretty bullet proof. Bosch appliances, also, are pretty bullet-proof. It's all according to a mix of decent manufacture and pure blind luck.   Peter Wieck Melrose Park, PA

dplatt@coop.radagast.org (Dave Platt): Nov 21 12:12PM -0800 In article <l3d63c93jobjuht7hpsd04i5fghuf66pu4@4ax.com>, >dozens, all different brands and values. This is not due to crappy >manufacturing, but rather due to careful selection for the MINIMUM >lifetime of the component.   That's an "honorable" American tradition that dates back at least a century. The story goes that Henry Ford has his engineers buy and disassemble scrapped Ford cars, to see which parts had failed and which ones were still in good shape. He pointed out that the company could often save money by redesigning (more cheaply) parts which rarely failed... so the new versions would wear out and fail at about the same time as everything else.   I remember one of the Lord Darcy stories by Randall Garrett, which involved a (magic-based) process somewhat like this for the human body. The spells would draw upon the health of long-lived parts of the body, to support those which were more prone to obvious aging.   The recipient of this treatment might have the apparent health and vigor of one in his thirties, and sustain this for several decades (e.g. up until the age of 60 or so). At that point, all of the body systems would collapse simultaneously, and the patient would die of old age in the space of an hour or two.

"pfjw@aol.com" <pfjw@aol.com>: Nov 21 01:31PM -0800 Live fast. Die young. Leave a good looking corpse.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Nov 21 04:56PM -0800 Jeff Liebermann wrote:     > In the bad old daze, the electrolytics were running at 60Hz, not > 60KHz. The power (heat) dissipated in the electrolytics is a function > of frequency.   ** The heat loss in an electro is related to ripple current and ESR at the frequency in use. ESR is much HIGHER at 60Hz or 120Hz than it is at 60kHz - so losses are LOWER at high frequencies.   Also, ESR goes down with increasing temperature - by up 5 times at the max rated temp of the cap.   Running in a hot environment is the main cause of short lifetimes, eg with nearby heatsinks and no fan.         ..... Phil

ohger1s@gmail.com: Nov 21 04:56PM -0800 On Monday, November 21, 2016 at 1:07:20 PM UTC-5, Jeff Liebermann wrote:   > In the bad old daze, the electrolytics were running at 60Hz, not > 60KHz. The power (heat) dissipated in the electrolytics is a function > of frequency.   They've been using high frequency smps since the late 70s (Sony was the first that I can recall (and boy were they *squirrely*). And while we replaced capacitors on the wholesale level even back then, they didn't bulge. The vented cap syndrome (VCS?) has really only been an issue since about 2004 or so. Around 2008 was the real big explosion of top bulged caps, when we'd see TVs in warranty with bulged/vented caps. There's been a big slowdown in bulged caps in recent years.

dplatt@coop.radagast.org (Dave Platt): Nov 21 05:07PM -0800 In article <9234021a-116c-431f-ba5b-7cb11400d692@googlegroups.com>, >(VCS?) has really only been an issue since about 2004 or so. Around 2008 was the >real big explosion of top bulged caps, when we'd see TVs in warranty with >bulged/vented caps. There's been a big slowdown in bulged caps in recent years.   Sounds like this might be the "capacitor plague" problem? Bad water-based electrolyte?   https://en.wikipedia.org/wiki/Capacitor_plague

Phil Allison <pallison49@gmail.com>: Nov 21 05:20PM -0800 Jeff Liebermann wrote:       > Notice that the SEC-1235 is a 12V 30A device and > current limits at 35A. How many amps are you drawing?   ** Transceivers tend to draw a LOT LESS current while in receive mode - which is the only time PSU generated RF noise might be a problem. SMPSs often send a fair amount of RFI back up the AC power cable, even when running at low power outputs which makes them troublesome when used with radio receivers - especially in the lower part of the HF band.   The OP's supply may have deteriorated components ( plastic film caps most likely ) in the filter fitted to the incoming AC line. Only way to know for sure is to get another, similar supply and try it.   If the OP has a linear 12V supply that can run the transceiver in receive mode, he should try that too.       ..... Phil

lagagnon@gmail.com: Nov 21 07:20PM -0800 I will respond to some of the posts above, without discussing the side topic of poorly manufactured capacitors etc.   1) the PS is rated at 35A, but I rarely draw more than 18A - and that is not a continuous draw. 2) I run the PS in a cool room, and also as a result of point 1 above the cooling fan has never come one (but has been tested to work). In other words the PS runs very cool 3) nothing has changed for 7 years until recently so this is definitely recent noise coming from the PS as I can switch to a deep cycle battery instantly and the RX noise disappears.   I have ordered the two 1000uF, 200V input caps and should replace them in about 3 days and will let you all know the results.

Jeff Liebermann <jeffl@cruzio.com>: Nov 21 09:15PM -0800 >I will respond to some of the posts above, without discussing >the side topic of poorly manufactured capacitors etc.   Sorry for the topic drift, but my intuition tells me that the noise is somehow related to the bulging caps.   >1) the PS is rated at 35A, but I rarely draw more than 18A - >and that is not a continuous draw.   That's nice. Now, for the 2nd time, will you kindly disclose the model number of the power supply. Is it this one? <http://www.samlexamerica.com/products/ProductDetail.aspx?pid=66>   >2) I run the PS in a cool room, and also as a result of point >1 above the cooling fan has never come one (but has been tested >to work). In other words the PS runs very cool   I didn't suggest that the power supply was overheating. I suggested that the capacitors might be overheating from too much ripple current. I also suggested that you use an IR thermometer to measure the case temperature of the capacitors.   >3) nothing has changed for 7 years until recently so this is >definitely recent noise coming from the PS as I can switch to a >deep cycle battery instantly and the RX noise disappears.   Nothing has changed is what all my customers say. Nothing means nothing that is obvious to them. In most cases, that's a polite way for them to suggest that I not pry too deeply into what the customer has been doing with the device. If I do pry, I often find questionable practices. I had one like that 2 days ago. Nothing had changed in years before the computer crapped out. Too bad the fan and most of the insiders were packed with cat hair.   >I have ordered the two 1000uF, 200V input caps and should replace >them in about 3 days and will let you all know the results.   I rarely have any problems with the input caps. It's the lower voltage caps that blow.   -- 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

ohger1s@gmail.com: Nov 22 04:25AM -0800 On Tuesday, November 22, 2016 at 12:15:58 AM UTC-5, Jeff Liebermann wrote:     > I rarely have any problems with the input caps. It's the lower > voltage caps that blow.   Not common, but not unheard of. I've replaced a bunch of 450V PFC capacitors in smps that don't show signs of venting, but they're dead and when removed, feel like half the weight of what they should be. They also "rattle" inside as the assy inside has shrunk.

avagadro7@gmail.com: Nov 21 04:00PM -0800 NO   http://www.google.com/#q=115V+GROUNDED+ELECTRICAL+WIRE+CONNECTOR&tbs=vw:l&tbm=shop&start=0   Lowes has a selection. The lower cost plugs melted here in an auto DC/inverter/charger.   See if Lowes has Levitons   Grainger will come thru with quality for industrial applications. Lowes ?

avagadro7@gmail.com: Nov 21 04:09PM -0800 > Lowes has a selection. The lower cost plugs melted here in an auto DC/inverter/charger.   > See if Lowes has Levitons   > Grainger will come thru with quality for industrial applications. Lowes ?   http://www.alliedelec.com/circular-connectors/circular-connectors/

AlfySande <jo-SpamtraP-hn@yahoomail.com>: Nov 21 07:54PM +0100 > is rated at a higher voltage than the application).   > Peter Wieck > Melrose Park, PA   Hi...i am a new user here. As per my knowledge the bad batteries caused the electronic controller to draw too much current in an attempt to maintain speed.That's just a guess, though. It is hard disagnose something with no information.         -- AlfySande

"pfjw@aol.com" <pfjw@aol.com>: Nov 21 12:10PM -0800 On Monday, November 21, 2016 at 2:17:10 PM UTC-5, AlfySande wrote:   > the electronic controller to draw too much current in an attempt to > maintain speed.That's just a guess, though. It is hard disagnose > something with no information.     I think you left out a step:   a) The batteries ran low. b) The user kept 'upping' control to maintain speed. c) As long as the motor is turning, things are (mostly) OK. d) The motor (brush-type) stops dead, but the speed control is still on MAX. e) Now the full - remaining - battery capacity is going through the fuse. f) *POOF*   But, the batteries are sulphated, the speed controller has been overheated, the motor overheated - or at least those commutator contacts arced. Altogether a mess.   Any properly designed system would have a condition meter and a low-battery cut-off to prevent this. And a thermal breaker in addition to the fuse.   Peter Wieck Melrose Park, PA

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