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Doug White <gwhite@alum.mit.edu>: Nov 23 04:03PM I have a couple small magnetic-base gooseneck work lights mounted on my milling machine. They were designed for 20W 12V MR-16 halogen bulbs, but those get really HOT. After scorching myself a couple times bumping into them, I switched to LED replacements that draw about 1/5th the power of the halogens.   They have C&K garden variety 6A 125V slide switches mounted on the back end. After relatively infrequent use (I only run the mill a couple days a month), the switch on one became intermittent. I installed an identical switch & it's been fine.   Just recently, the switch on the 2nd light has started exhibiting the exact same symptoms. I don't want to keep replacing these things. They are pop-riveted in place (no easy way to get at a nut inside), and swapping them out every few years is annoying. I always thought C&K made decent switches, and of the options on Digikey, they are the most expensive.   Are there other brands I should consider trying, or do people think I just got ones from a bad batch?   The only other thing I can think of is that the LED bulbs may have a funny startup surge that is cooking the contacts. I didn't do a post- mortem on the first one, but the contacts should be loafing at the reduced load they are seeing.   Suggestions welcome.   Thanks!   Doug White

MOP CAP <email@domain.com>: Nov 23 08:31AM -0800 On 2016-11-23 16:03:42 +0000, Doug White said:     > Suggestions welcome.   > Thanks!   > Doug White   This does not supprise me. Switches designed for switching a faire amount of power do not work very well on low power or "dry" circuits. Your LED's are essentally such a circuit. You probably cannot find a slide switch that is designed for "dry" circuits. Even if you did the next person that comes along might replace the LED's with the original halogen bulbs and burn out the switch. No solution just info. CP

Cursitor Doom <curd@notformail.com>: Nov 22 09:38PM has anyone got any tips as to how to deal with these? Some of the pots and rotary switches I come across seem (at first sight at any rate) to be fully encased and consequently very difficult (and some) to get any lubricant into. I reckon there must be some old trick or knack I'm not familiar with. Is there any alternative to removing them outright and soaking them or drilling tiny holes in the casings to squirt lube in through?

"pfjw@aol.com" <pfjw@aol.com>: Nov 22 01:54PM -0800 On Tuesday, November 22, 2016 at 4:39:35 PM UTC-5, Cursitor Doom wrote: > familiar with. Is there any alternative to removing them outright and > soaking them or drilling tiny holes in the casings to squirt lube in > through?   I have this wonderful little device made from a bit of brass tubing, a threaded fitting soldered onto it and a small piston that seals with O-rings - almost like a very primitive syringe.   How it works: The threaded fitting has a small O-ring inside and is threaded onto the switch or pot until it seals. Lubricant is introduced and the piston inserted. By activating the piston, the lubricant is then forced around the shaft into the guts of the pot or switch.   Works like a charm. The tube is a few inches long to accommodate different shaft lengths, but one does not have to fill the thing. The piston (if made correctly) seals the tube so that the lubricant is directed into the pot. The pot just needs to face UP.   Peter Wieck Melrose Park, PA

Cursitor Doom <curd@notformail.com>: Nov 22 11:50PM > How it works: The threaded fitting has a small O-ring inside and is > threaded onto the switch or pot until it seals.   What thread are you talking about here? The one the shaft revolves inside of that's used for securing the pot/switch to the front panel?? Can't see how that would work. :-/

dplatt@coop.radagast.org (Dave Platt): Nov 22 04:24PM -0800 In article <o12lki$gvd$15@dont-email.me>,   >What thread are you talking about here? The one the shaft revolves inside >of that's used for securing the pot/switch to the front panel?? Can't see >how that would work. :-/   http://www.premierguitar.com/articles/a-pot-cleaning-miracle-1 mentions a somewhat similar device.   Consider the simple case - a hollow tube, with inside threads that match those around the outside of the pot's bushing (the one you screw the retaining nut onto). Screw this on, hold the pot with the tube pointing upwards, and pour or spray a suitable cleaning solution into the top of the tube. It flows down, and surrounds the pot's shaft (which comes out through the bushing).   The shaft is not hermetically sealed to the bushing - it can't be. There's always going to be a small gap between the outside of the shaft, and the inside of the bushing... and the cleaning solution can flow through this gap and into the inside of the pot.   For a "fully sealed" pot, this gap's going to be quite small - there may be an O-ring seal inside, I suppose. So, you may need to pressurize the cleaning solution to force it into the pot. That can be done by forcing a piston of some sort into the tube, or by attaching a syringe to the top of the tube (via a sealed cap) and squirting/pressurizing that way, or etc.   A guy named Bill Turner used to sell an injection tool of that sort, and also sold oleic acid (which can be diluted in naptha to create something a bit like the original Cramolin Red contact cleaner). I don't think he's still in business, though.

Phil Allison <pallison49@gmail.com>: Nov 22 04:50PM -0800 Cursitor Doom wrote: > familiar with. Is there any alternative to removing them outright and > soaking them or drilling tiny holes in the casings to squirt lube in > through?   ** Drilling a small hole is your safest bet.   It always works and will not remove the grease packed into the shaft bearing and ruin the control's nice feel as with the other idea posted here.   FYI;   just serviced some early 60s UK made valve audio that used fully sealed, ganged pots for volume, balance, bass & treble.   Not a sign of noise in any of them.       .... Phil

"Michael A. Terrell" <mike.terrell@earthlink.net>: Nov 22 09:10PM -0500 Dave Platt wrote: > and also sold oleic acid (which can be diluted in naptha to create > something a bit like the original Cramolin Red contact cleaner). I > don't think he's still in business, though.     Someone else now has the domain name for Turner's website.     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

ohger1s@gmail.com: Nov 22 07:14PM -0800 On Tuesday, November 22, 2016 at 9:10:35 PM UTC-5, Michael Terrell wrote:   > > don't think he's still in business, though.   > Someone else now has the domain name for Turner's website.   > --   Bill's health was always been nebulous since he started on the web. I think he's still alive, but with his eyesight being what it is and other health issues, he had to give up the hobby. Too bad. A very innovative guy who sold wares for barely more than it cost him, and he gave his knowledge freely.

gregz <zekor@comcast.net>: Nov 23 08:46AM >> something a bit like the original Cramolin Red contact cleaner). I >> don't think he's still in business, though.   > Someone else now has the domain name for Turner's website.   Sometimes I use the red nozzle against seams, and often gets inside enough to do the job. Sprays have them, WD40, CRC 2-26, Deoxit. A little alcohol or naphtha mixed with oleic acid gets into cracks.   Greg

"Ron D." <Ron.Dozier@gmail.com>: Nov 22 08:03PM -0800 What fuse is a good question.   Is there a possibility that the "wrong battery type" was put in the buggy? i.e. a battery that does not like deep discharge replaced for one that would. A "car battery" pretty much would die quickly if it discharged too far.   A defect with the charger is another possibility. Loose connections can kill the electronics responsible for charging.

"pfjw@aol.com" <pfjw@aol.com>: Nov 22 10:46AM -0800 Please note the interpolations:   On Monday, November 21, 2016 at 7:21:09 PM UTC-5, Robert Bannon wrote:   > Right?   > For example, what's household bleach? > It's just diluted bleach.   Sure, anything from about 2% to about 5% sodium hypochlorite. And why is it diluted? So that the user stands a chance of not being damaged by accidental misuse. As simple as micturating into a toilet with a bleach concentrate in it. > What is nail polish remover? > It's just pretty smelling diluted acetone or ethyl acetate.   Yes, as either is explosive if misused, spilled, or concentrated in a closed room. 2.5% to 13%. & 3.3% to 9% respectively. And both have exceedingly low flash points. > What is rubbing alcohol? > It's just vastly diluted isopropyl alcohol.   70% is diluted. 91% less so, and 100% is readily available. But the vapor pressure is far lower than acetone or ethanol, and so far less dangerous. Still, explosive at 2.2%   > Why not just use the concentrate? > Concentrated pool bleach is what I use in my washing machine.   You dress all in white or use solution-dyed man-made fabrics, then?   > Concentrated muriatic acid is what I use in my toilet bowl.   If it is called 'concentrated' and 'muriatic acid', it is not as much of a joke, but it is not glacial hydrochloric acid. THAT is the concentrate. And in any case you had best be on a municipal sewer system as you are making short work of your septic system using concentrated bleach and acids.   > Pure acetone is what my kids use for removing nail polish.   Ah, so you are looking for as much collateral damage as possible when you collect your Darwin Award? And you are teaching your kids all this as well? > 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.   If you were to live alone and away from anyone else, why not? But as it is, you are concentrating a large number of dangerous chemicals in dangerous forms in the same house as your family.   > 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.   So is Acetone & Ethanol. Bleach is corrosive and can release chlorine, chloramine gas and react badly with any number of materials making very toxic byproducts. Acetone and Ethanol are explosive, damage a great many plastics and finishes, and are very often abused in and of themselves.   Muriatic (*hydrochoric*) acid is one of the most active acids on the planet, and will react with many things in any concentration at all. It is also colorless and odorless, burns skin very nearly instantly and much more. Mixed with many common household chemicals it can release compounds that are exceedingly deadly. These include hydrogen sulphide, straight chlorine gas, even igniting (as in fire) steel wool. That burns VERY hot.     > 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.   There are distillates and there are distillates. Gasoline is Benzene based. Most household chemicals are not. And if you do not understand the fundamental differences between the two, you well and truly are hopeless.   I hope that your family is at/past the 'leaving home' stage as you are, truly, a disaster in the making.   Peter Wieck Melrose Park, PA

"pfjw@aol.com" <pfjw@aol.com>: Nov 22 01:32PM -0800 http://darwinawards.com/darwin/darwin2012-03.html   As one example. There are thousands around gasoline.     Peter Wieck Melrose Park, PA

Robert Bannon <rbannon@yahoo.spam.nowhere.invalid>: Nov 23 04:00AM On Tue, 22 Nov 2016 12:16:53 GMT, Wayne Chirnside wrote:   > Mineral oil works for me for many types of goop - adhesive.   I like that idea, and will try it. Especially since a bunch of you use an "oil" to coat the paper labels ahead of time to "soak" through the paper.   I don't do that since I use water to soak paper labels off. But the "oil", if it works, would be a great solution.

lagagnon@gmail.com: Nov 22 09:46AM -0800 On Monday, 21 November 2016 21:15:58 UTC-8, Jeff Liebermann wrote:     > 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>   Yes, that's the one. Does that make a difference to your assessment? > I didn't suggest that the power supply was overheating. I suggested > that the capacitors might be overheating from too much ripple current.   OK, I understand, and I wonder whether the output caps which I've replaced have blown because the input caps are not as effective at removing ripple?   > 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.   How is that relevant to my post and my situation?     > I rarely have any problems with the input caps. It's the lower > voltage caps that blow.   See my suggestion above....

Tim R <timothy42b@aol.com>: Nov 22 01:31PM -0800 On Monday, November 21, 2016 at 3:12:13 PM UTC-5, Dave Platt wrote: > 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.   Much further back than that:   by Oliver Wendell Holmes (1809-1894) Have you heard of the wonderful one-hoss shay, That was built in such a logical way It ran a hundred years to a day, And then, of a sudden, it — ah, but stay, I'll tell you what happened without delay, Scaring the parson into fits, Frightening people out of their wits, — Have you ever heard of that, I say?   Seventeen hundred and fifty-five. Georgius Secundus was then alive, — Snuffy old drone from the German hive. That was the year when Lisbon-town Saw the earth open and gulp her down, And Braddock's army was done so brown, Left without a scalp to its crown. It was on the terrible Earthquake-day That the Deacon finished the one-hoss shay.   Now in building of chaises, I tell you what, There is always somewhere a weakest spot, — In hub, tire, felloe, in spring or thill, In panel, or crossbar, or floor, or sill, In screw, bolt, thoroughbrace, — lurking still, Find it somewhere you must and will, — Above or below, or within or without, — And that's the reason, beyond a doubt, A chaise breaks down, but doesn't wear out.   But the Deacon swore (as Deacons do, With an "I dew vum," or an "I tell yeou") He would build one shay to beat the taown 'N' the keounty 'n' all the kentry raoun'; It should be so built that it couldn' break daown: "Fur," said the Deacon, "'tis mighty plain Thut the weakes' place mus' stan' the strain; 'N' the way t' fix it, uz I maintain, Is only jest T' make that place uz strong uz the rest."   So the Deacon inquired of the village folk Where he could find the strongest oak, That couldn't be split nor bent nor broke, — That was for spokes and floor and sills; He sent for lancewood to make the thills; The crossbars were ash, from the straightest trees, The panels of white-wood, that cuts like cheese, But lasts like iron for things like these; The hubs of logs from the "Settler's ellum," — Last of its timber, — they couldn't sell 'em, Never an axe had seen their chips, And the wedges flew from between their lips, Their blunt ends frizzled like celery-tips; Step and prop-iron, bolt and screw, Spring, tire, axle, and linchpin too, Steel of the finest, bright and blue; Thoroughbrace bison-skin, thick and wide; Boot, top, dasher, from tough old hide Found in the pit when the tanner died. That was the way he "put her through." "There!" said the Deacon, "naow she'll dew!"   Do! I tell you, I rather guess She was a wonder, and nothing less! Colts grew horses, beards turned gray, Deacon and deaconess dropped away, Children and grandchildren — where were they? But there stood the stout old one-hoss shay As fresh as on Lisbon-earthquake-day!   EIGHTEEN HUNDRED; — it came and found The Deacon's masterpiece strong and sound. Eighteen hundred increased by ten; — "Hahnsum kerridge" they called it then. Eighteen hundred and twenty came; — Running as usual; much the same. Thirty and forty at last arrive, And then come fifty, and FIFTY-FIVE.   Little of all we value here Wakes on the morn of its hundreth year Without both feeling and looking queer. In fact, there's nothing that keeps its youth, So far as I know, but a tree and truth. (This is a moral that runs at large; Take it. — You're welcome. — No extra charge.)   FIRST OF NOVEMBER, — the Earthquake-day, — There are traces of age in the one-hoss shay, A general flavor of mild decay, But nothing local, as one may say. There couldn't be, — for the Deacon's art Had made it so like in every part That there wasn't a chance for one to start. For the wheels were just as strong as the thills, And the floor was just as strong as the sills, And the panels just as strong as the floor, And the whipple-tree neither less nor more, And the back crossbar as strong as the fore, And spring and axle and hub encore. And yet, as a whole, it is past a doubt In another hour it will be worn out!   First of November, 'Fifty-five! This morning the parson takes a drive. Now, small boys, get out of the way! Here comes the wonderful one-hoss shay, Drawn by a rat-tailed, ewe-necked bay. "Huddup!" said the parson. — Off went they. The parson was working his Sunday's text, — Had got to fifthly, and stopped perplexed At what the — Moses — was coming next. All at once the horse stood still, Close by the meet'n'-house on the hill. First a shiver, and then a thrill, Then something decidedly like a spill, — And the parson was sitting upon a rock, At half past nine by the meet'n-house clock, — Just the hour of the Earthquake shock! What do you think the parson found, When he got up and stared around? The poor old chaise in a heap or mound, As if it had been to the mill and ground! You see, of course, if you're not a dunce, How it went to pieces all at once, — All at once, and nothing first, — Just as bubbles do when they burst.   End of the wonderful one-hoss shay. Logic is logic. That's all I say.

whit3rd <whit3rd@gmail.com>: Nov 22 02:59PM -0800 > 1) the PS is ... > 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.   The input filter capacitors serve no RF function, so won't solve anything related to RF noise.

Phil Allison <pallison49@gmail.com>: Nov 22 05:41PM -0800 whit3rd wrote:   > > in about 3 days and will let you all know the results.   > The input filter capacitors serve no RF function, so won't solve anything > related to RF noise.   ** The OP is clutching at straws, big fat & expensive ones at that.   He ought to very carefully check the AC supply connection from his PSU to ground - any resistance there due to tarnished pins would send EMI way up.   BTW:   a portable AM-SW radio can be used to "sniff" for the source of the EMI.     .... Phil

Adrian Caspersz <email@here.invalid>: Nov 22 07:01PM On 22/11/16 15:59, Ralph Mowery wrote:   >> The battery is new and fully charged.   >> What could be the reason? TIA for any suggestions.   > Probably bad capacitors on the mommy board.   Have they been told to stand in the corner?   OP, Try this step by step.   Unplug the power adapter. Pull out the laptop's battery. Press and hold down the Power button for 45-60 seconds. Release the Power button. Put the battery back in the laptop and try starting it.   -- Adrian C

Jon Elson <jmelson@wustl.edu>: Nov 22 03:23PM -0600 N_Cook wrote:     > 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   Yes, if it is bad caps, it will be much happier warm, and really hard to get running when cold.   Jon

Cursitor Doom <curd@notformail.com>: Nov 22 09:18PM On Sun, 20 Nov 2016 15:03:44 -0800, shaheedamirkhan wrote:   > hello can anyone tel me the value of the thermistor ??   Sure. 21.2kVA

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