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mike <ham789@netzero.net>: Jan 30 11:16PM -0800 On 1/30/2018 6:55 AM, (PeteCresswell) wrote:   > Has anybody rebuilt one?   > Would I be naive thinking that all I need to do is   > - Obtain replacement cells Assumes you can find QUALITY replacement cells. You want HIGH CURRENT cells like used in power tool batteries. High CAPACITY cells rarely have HIGH CURRENT capability. Anything you buy on EBAY with "fire" in the name probably won't be satisfactory. Purchased in low quantity, QUALITY cells probably cost as much as a new battery. If they're 18650 cells, Lowe's sells a Kobalt tool battery for $10. Contains six QUALITY HIGH CURRENT cells.   > - Gracefully crack the case Can't tell from the picture whether those are screws holding it together. If it's glued... My favorite trick is to whack the seam with a sharp wood chisel and a hammer. Slow wont' do it. You need a high impulse whack with a low mass hammer wielded at high speed to crack the seal. It's very easy once you get the hang of it.   > - Figure out how to connect the new > cells The circuit is trivial. Your problem is the spot welder you need to hook 'em up. DO NOT under any circumstances solder to the cells. If you start with tabbed cells, or remove tabbed cells from something like the Kobalt pack, you can often salvage enough of the old tab that you can solder the tabs quickly without hurting the cell.   > - Replace the old cells with new cells   Sometimes, this works. Other times, the battery protection circuit notices that you removed power and commits suicide. Without special equipment and the secret sauce, you can't recover the pack. Some have claimed that they hook up another set of cells to keep it alive while they remove and replace the cells. Never tried that.   > - Close up the case   I spent more than a decade trying to rebuild laptop batteries. I can point to exactly ONE success. And I have a spot welder. Vendors try very hard to prevent you rebuilding the pack. It's a big liability issue for them. It can be a big issue for you if you damage something and it sets your house on fire.   Bottom line...go buy a new battery.

N_Cook <diverse@tcp.co.uk>: Jan 31 11:38AM On 30/01/2018 14:55, (PeteCresswell) wrote: > cells   > - Replace the old cells with new cells   > - Close up the case   Check the charger as well. A nimh version I looked at recently, intermittent shorted wires on the the charger had drained the battery to internal dendriting or such.

bitrex <bitrex@de.lete.earthlink.net>: Jan 30 07:06PM -0500 The PC that had this Nvidia GTX 670 graphics card in it refuses to start any recent variant of Linux I try on it via a USB live installer, it shows the boot/BIOS and splash screens OK but ends up with a black screen or garbled graphics. Still not sure if it's a hardware or driver issue, but...   This is the side of the GPU PCB facing upwards in the tower:   <https://www.dropbox.com/s/1jq330axgnvlj7l/IMG_20180130_185355206.jpg?dl=0>   Looks like thermal grease dripped all over it from somewhere. Related?

Terry Schwartz <tschw10117@aol.com>: Jan 30 04:37PM -0800 Have you verified that it's thermal grease? Looks almost like some form of corrosion.

Rheilly Phoull <rheilly@bigslong.com>: Jan 31 08:47AM +0800 On 31/01/2018 8:06 AM, bitrex wrote:   > This is the side of the GPU PCB facing upwards in the tower:   > <https://www.dropbox.com/s/1jq330axgnvlj7l/IMG_20180130_185355206.jpg?dl=0>   > Looks like thermal grease dripped all over it from somewhere. Related?   Did you clean it off ??

dansabrservices@yahoo.com: Jan 30 05:20PM -0800 This card is toast. The white stuff is corrosion from most likely water or some other spilled liquid. Given the extent of the corrosion, I would doubt that this card is salvageable. The corrosion has likely eaten through the contacts under some of the ICs.   You can try cleaning this off, but I doubt it will help.   Dan

Tekkie® <Tekkie@comcast.net>: Jan 30 03:17PM -0500 Clare Snyder posted for all of us...       > Better than 90% of vehicles with standard transmissions today have > NO MANUAL ADJUSTMENT PROVISIONS.   > Mad MaX is an IDIOT.   I wonder if this is the clutch he "replaced"?   He doesn't know the olde heat and bend the rod trick... maybe use some all thread and burn an adjustment hole in the floorboard.   -- Tekkie

Tekkie® <Tekkie@comcast.net>: Jan 30 03:21PM -0500 Clare Snyder posted for all of us...     > point of "blowing smoke" he was restricted to using Bic stick pens > (pencils were no good because a pencil sharpener was beyond his level > of comprehension)   Sharp as a marble aye?   -- Tekkie

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"(PeteCresswell)" <x@y.Invalid>: Jan 30 09:55AM -0500 One of these Bad Boyz: http://tinyurl.com/ydbb7jj7   Has anybody rebuilt one?   Would I be naive thinking that all I need to do is   - Obtain replacement cells   - Gracefully crack the case   - Figure out how to connect the new cells   - Replace the old cells with new cells   - Close up the case -- Pete Cresswell

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N_Cook <diverse@tcp.co.uk>: Jan 26 09:01AM On 26/01/2018 01:27, Jeff Liebermann wrote: > Elmer's wood glue > Elmer's Craft Bond Rubber cement   > Back to watching the glue dry... Thanks.   Store superglue in sealed jamjars with a transparent sachet of activated silica gel or if in a sachet thensome loose crystals in the jar also ,no trouble after 5 years. Use gel with a colour indicator for dry/damp, not too obvious with plain white/off-white colour of damp/dry silica crystals

gregz <zekor@comcast.net>: Jan 26 09:03AM > shortly afterwards a parcel arrived with 12 tubes of the correct "neutral cure" type.   > Unfortunately, most of the 12 tubes had gone rock hard they were so old.   > .... Phil   I never found acid cure do much of anything to copper. I put some on circuit board to test. Contrary to reading, i believe the stuff passes moisture and corrode metal underneath.   Greg

gregz <zekor@comcast.net>: Jan 26 09:08AM > Elmer's wood glue > Elmer's Craft Bond Rubber cement   > Back to watching the glue dry... Thanks.   I often use GOOP as it's tuff, sticks well, slightly flexible. Also similar E6000. takes some days to fully dry. Stuff evaporates from tube if put on wrong.     Greg

tabbypurr@gmail.com: Jan 26 03:27AM -0800 On Friday, 26 January 2018 01:27:23 UTC, Jeff Liebermann wrote: > Elmer's wood glue > Elmer's Craft Bond Rubber cement   > Back to watching the glue dry... Thanks.   I've got epoxy in plastic tubes bought somewhere around 15 years ago, it's still fine.   The rest probably is nothing new... Cyanoacrylate never keeps well, but I've not tried anything special with it. Glues generally last best afer opening if capped off with ali foil, for containers that have no lid. Plastic film just doesn't do it. White pva lasts over a decade no problem, but some can moulder in the gallon container. Bitumen glue lasts well if the solvent doesn't disappear, it can always be redissolved with paraffin/kerosene. Never use diesel.     NT

Terry Schwartz <tschw10117@aol.com>: Jan 26 05:32AM -0800 Jeff, you ARE the authority on most everything, so I probably should bow to your expertise. (But I won't) After all, you have been in the repair biz too long.   Re-read Phils post -- he did not mention refrigeration "not working". He said the replacement tubes were "so old".   Double unstated? What does that even mean? Obviously if it's unstated, even 1 day is potentially double that.   YES I've had success refrigerating adhesives and silicones. Cold always slows chemical reactions, it's basic chemistry. I've had sealed tubes of caulk last 5 years in my garage fridge. Please be cautious about accusing me of "contriving" anything.   I also refrigerate batteries, and I've got some Panasonic industrial C cells that are still at full cell voltage after more than 10 years.   So you did find something regarding shelf life? Or not? Which is it?   Unopened tubes of adhesive, if well manufactured and packaged, seem to last a long time. I've had silicones and cyanoacrylates last for many years. I have limited experience with epoxies, but one tube of plastic-specific epoxy has lasted at least two years -- even after being opened.   I almost always seem to be able to find a manufacture date on the tube, either printed or on a crimp. Not so much on the tiny drugstore "superglue" packages. Reputable manufacturers commonly publish a short number for shelf life, (sometimes you have to actually ask for it) as you saw, 12 months, but in reality, that is a CYA number so that the consumer will 1) not be disappointed when his 2 year past date product goes bad, and 2) feel the need to buy another tube and when the stuff only *might* be bad. Helps revenue.   I've found 3+ year old product on the shelves in the orange big box home stores. Caveat Emptor. Their warehouses do not have a FIFO system, and are not climate controlled.

tabbypurr@gmail.com: Jan 26 06:45AM -0800 On Friday, 26 January 2018 13:32:19 UTC, Terry Schwartz wrote:   > I also refrigerate batteries, and I've got some Panasonic industrial C cells that are still at full cell voltage after more than 10 years.   I've still got some unrefrigerated ZnC & alkaline cells almost twice that age, so yours should last a long time yet. What I notice is that while most keep, a minority go from full to zero at some point. It's as if some sort of fault occurs internally and they then drain out.     NT

Harold Newton <harold@example.com>: Jan 26 03:00PM On Thu, 25 Jan 2018 17:27:13 -0800, Jeff Liebermann wrote: > So, in your experience, what are the approximate shelf lives of these > common adhesives? > RTV sealant   REF: <https://groups.google.com/forum/#!topic/sci.electronics.repair/t5xXvDn_T-U>   I have ten year old unopened Toyota FIPG (aka RTV) that I "hope" to use for a valve cover gasket. I "hope" it's still good.   I do know that the tube of Home Depot gray-putty-like two-part "tootsie-roll" epoxy (with the cream in the middle) does NOT last more than about 5 years (ask me how I know).   The epoxy still works, but once opened, and half used, the rest dries out easily (I didn't re-wrap it though).   Likewise with "opened" cyanoacrylate ... I buy the *smallest* tubes I can find, because, to me, they're single-use only. They may last a few weeks once opened, maybe even a few months ... but not more than that.   The bigger bottles get runny ... like water ... and never stick, in my experience.

Phil Allison <pallison49@gmail.com>: Jan 26 02:24AM -0800 jurb...@gmail.com wrote:   -------------------------   > >"** Horrible idea - it shorts the signal at low settings and sends the > > output impedance high just when you want it low for noise/hum reasons. "   > Isn't that how some guitar pickups are wired ? And don't ask me why.   ** Only very rarely. That method has just *one* advantage where there are multiple PUs, each with its own volume pot. It forms a resistive mixer that allows signal to pass from any pickup to the output regardless of the other pot settings.   The usual method requires no control be zeroed when PUs are switched in parallel or the instrument becomes silent.   The wiring schemes used in most electric guitars are primitive, full of dodges and compromises - good examples of how NOT to do it.     See wiring for early Gibson models.   http://archive.gibson.com/Files/schematics/lespaul2.gif         .... Phil

jurb6006@gmail.com: Jan 26 05:48AM -0800 >"Strangely, I have not come across a reverse linear pot anywhere. "   Now I wonder what kind of taper is used in the pots in a graphic equalizer. Double reverse anti-log or some bizarre shit like that ?

Fox's Mercantile <jdangus@att.net>: Jan 26 08:33AM -0600 >> "Strangely, I have not come across a reverse linear pot anywhere."   > Now I wonder what kind of taper is used in the pots in a graphic > equalizer. Double reverse anti-log or some bizarre shit like that ?   For fuck's sake. Am I the only one here that got the joke?     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Jan 26 06:47AM -0800 On Friday, 26 January 2018 14:33:49 UTC, Fox's Mercantile wrote: > >> "Strangely, I have not come across a reverse linear pot anywhere."   > > Now I wonder what kind of taper is used in the pots in a graphic > > equalizer. Double reverse anti-log or some bizarre shit like that ?   I don't know, but would expect linear.   > For fuck's sake. Am I the only one here that got the joke?   someone hasn't been paying attention     NT

Mike Coon <gravity@mjcoon.plus.com>: Jan 26 10:10AM In article <bd8b72ee-2cce-4d75-bf27-aa3d0f14a907@googlegroups.com>, tabbypurr@gmail.com says...   > I sure am grateful that computing has improved. Funny that such a HDD was the latest & greatest thing at the time.   My favourite when I worked for Univac was the FastRand (Remington Rand vs Random; geddit?). See https://en.wikipedia.org/wiki/UNIVAC_FASTRAND   Pity no photo there - https://www.fourmilab.ch/documents/univac/fastrand.html   They were amazing beasts; quote: "No UNIVAC programmer who ever encountered a FASTRAND is likely to forget it."   Mike.

jack4747@gmail.com: Jan 26 02:20AM -0800 Il giorno venerdì 26 gennaio 2018 00:33:20 UTC+1, Jon Elson ha scritto: > platters that allows the heads to land on them without damage. (They may > have a dedicated landing area with no data written there.)   > Jon   No.   https://en.wikipedia.org/wiki/Disk_read-and-write_head Paragraph "Description"   When the HD is powered off, the heads are "parked" outside of the platters.   Bye Jack

jack4747@gmail.com: Jan 26 02:21AM -0800 > Paragraph "Description"   > When the HD is powered off, the heads are "parked" outside of the platters.   > Bye Jack   Here more pictures (and explanations):   http://www.data-master.com/HeadCrash-explain-hard-disk-drive-fail_Q18.html   Bye Jack

tabbypurr@gmail.com: Jan 26 03:30AM -0800 On Thursday, 25 January 2018 23:33:20 UTC, Jon Elson wrote: > platters that allows the heads to land on them without damage. (They may > have a dedicated landing area with no data written there.)   > Jon   I read about some laptop HDDs taking the head off-platter during the noughties to improve shock survival.     NT

tabbypurr@gmail.com: Jan 26 03:33AM -0800 On Friday, 26 January 2018 10:10:36 UTC, Mike Coon wrote:   > They were amazing beasts; quote: "No UNIVAC programmer who ever > encountered a FASTRAND is likely to forget it."   > Mike.   "There were reported cases of drum bearing failures that caused the machine to tear itself apart and send the heavy drum crashing through walls."     NT

jurb6006@gmail.com: Jan 26 05:42AM -0800 On Wednesday, January 24, 2018 at 12:18:36 PM UTC-5, KenO wrote:   > Then decided to try http://www.repairfaq.org and searched with how test "Hard drives" but only got "The Drexel mirror site of the Sci.Electronics.Repair FAQ is temporarily unavailable..."   > Appreciate any suggestions   > Ken   Grab it by the end by the connectors and smack the SIDE of the drive in the direction to force rotation. You don't want to pull the heads off if they're only lightly stuck.   Also, sometimes when the bearings are that tight they seize up. This used to happen to the drum motor on VCRs sometimes.   But then before you smack anything try cold and heat of course. Heatwise it can stand up to maybe 140C or so. That would loosen up the grease and many ovens go that low. And sometimes, for reasons I haven't quite figured out completely, cold works. They can stand being in the freezer.   Once it spins, copy everything worth a shit on it of course. You might only get one chance.

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rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 08:11AM -0500 >> (H2) and oxygen (O2), not acid and base. Anything else would have to come >> from additives to the water.   > it's saltwater.   Not really. All water has contaminants. The water he has mentioned was fresh water with more or less contaminants. Still, it wouldn't be described as electrolysis of (salt)water if the interesting part was the contaminants. It would be described as the interesting bits dissolved in water.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Fox's Mercantile <jdangus@att.net>: Jan 25 10:30AM -0600 On 1/25/18 8:06 AM, Terry Schwartz wrote: > Apparently anyone can be an expert on things they do not understand.   As Rickman and Oldschool constantly prove.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 08:06AM -0500 >> refers to which direction the log curve goes, a log taper or an exponential >> taper. A linear taper is the same either way... it's linear.   > I would very much expect he didn't need to 'give it a thought' to work out something so obvious.   And yet, he mentions he has never seen a reverse linear taper.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

amdx <nojunk@knology.net>: Jan 25 08:00AM -0600 > JB Weld is your best friend. Get a soda-straw or heat-shrink tubing about the same diameter as the shaft, either use the broken piece or a suitable bit of solid material to extend the shaft to the correct length. Mix up the *SLOW* JB Weld epoxy, and use the straw/tubing to hold the shebang together and vertical, but out of the pot, until the epoxy sets up. Let the epoxy fill any voids. The result will be stronger than the original.   > Peter Wieck > Melrose Park, PA   I have repaired many broken plastic parts. I have a kit with 0.025" and 0.035" drill bits and matching steel rods. I put the parts together, then drill through where inserting a steel pin will give it the most strength. I epoxy the joint and the pin and put it all together. I use a Dremel tool to drill the hole and and cut the steel pin off, after the epoxy sets. The epoxy I have is Huntsman Fastweld 10, (ex. Ciba-Geigy Araldite) It is a 5 minute set 24 hour cure.   Mikek

amdx <nojunk@knology.net>: Jan 25 08:15AM -0600 > He got as far as the door before he caught on. And it never happened to him again. Others got all the way to the counter at the warehouse.   > Peter Wieck > Melrose Park, PA   In my late teens a father bought his daughter a Volkswagen Beetle, the first thing he did was send her to go to the gas station* and have them check the water in the radiator.   Mikek   * back when they had service at gas stations.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Jan 25 06:52AM -0800 > 1956 IBM 350. fifty 24-inch (0.6 m) platters, total capacity (3.75 megabytes).   > NT   More precisely, 5,000,000 Hollerith characters (the ones available on an IBM punch card). Each character was encoded using six bits. Since there were only 48 symbols defined, not all 64 of the six-bit combinations were possible.

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jurb6006@gmail.com: Jan 24 06:37PM -0800 >"I will try to put in the drop box."   Too bad. Dropbox doesn't want to display for me. It might be because I used to be a member ad gave it up. I am currently looking for free hosting that is compatible with my browser.   I don't mind an ad or two but I don't want people to have to sign up or sign in and that is what it is doing for me.

Ralph Mowery <rmowery28146@earthlink.net>: Jan 24 11:23PM -0500 In article <37301d83-be37-4233-9918-209e49cec2b1@googlegroups.com>, pfjw@aol.com says... > > works OK except for 1000...   > As already noted, there are almost as many codes as makers. In my (very) old Centerlab Catalog, I did find references to W-Taper pots, but nothing conclusive at all on K or k taper as a specific reference.   > With the additional hint of this being a slider, further googling got me to drill bits, but nothing on pots, linear or rotary.   All that is what makes things 'interisting'. I believe the K is for Kelvin temperature and that made them use the k for 1000.   Too bad that many companies seem ot use their own code for part numbers. I really hate the companies that use their part number on standard parts and if you need to replace them, you are almost forced to go to the origional company or one of their repair man. Friend in the auto repair business told me that often a luxulary car part would be the same as a less expensive model. They use a different number and higher price.

rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 12:05AM -0500 Phil Allison wrote on 1/23/2018 10:29 PM:   > The code letters used varied alarmingly, A originally meant linear and C =log. Pots coming from Asia used A = audio taper with B = linear and D = log.   > The code letter "E" referred to a "reverse log" pot, useful in instrumentation where the actual gain of a amplification stage must be varied smoothly.   > Strangely, I have not come across a reverse linear pot anywhere.   If you give it a thought, you will realize a linear pot is its own reverse. The reverse doesn't refer to whether the resistance goes up or down, it refers to which direction the log curve goes, a log taper or an exponential taper. A linear taper is the same either way... it's linear.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

whit3rd <whit3rd@gmail.com>: Jan 24 11:28PM -0800 On Wednesday, January 24, 2018 at 9:05:17 PM UTC-8, rickman wrote:   > If you give it a thought, you will realize a linear pot is its own reverse. > The reverse doesn't refer to whether the resistance goes up or down, it > refers to which direction the log curve goes...   Log taper means mimicing log(d) where the deflection (d) goes from 1 to 100 or somesuch. Inverse log taper means mimicing log(1/d) = - log(d)   So, linear taper can mimic 'd', and its inverse can be '-d', as you say. Or, linear taper can be 'd', and its inverse can be '1/d'.   The '1/d' taper would be a way to make an adjustable attenuator, linear in inverse gain going from '1' meaning full signal, to '2' meaning 1/2, ... '10' meaning 1/10

rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 02:57AM -0500 whit3rd wrote on 1/25/2018 2:28 AM: > Or, linear taper can be 'd', and its inverse can be '1/d'.   > The '1/d' taper would be a way to make an adjustable attenuator, linear in inverse gain > going from '1' meaning full signal, to '2' meaning 1/2, ... '10' meaning 1/10   Then it is no longer linear.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Fox's Mercantile <jdangus@att.net>: Jan 25 01:58AM -0600 On 1/24/18 11:05 PM, rickman wrote: > reverse. The reverse doesn't refer to whether the resistance goes up or > down, it refers to which direction the log curve goes, a log taper or an > exponential taper.  A linear taper is the same either way... it's linear.   Congratulations, not only are you ignorant, you have no sense of humor.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Jan 25 12:22AM -0800 On Thursday, 25 January 2018 05:05:17 UTC, rickman wrote: > The reverse doesn't refer to whether the resistance goes up or down, it > refers to which direction the log curve goes, a log taper or an exponential > taper. A linear taper is the same either way... it's linear.   I would very much expect he didn't need to 'give it a thought' to work out something so obvious.     NT

"pfjw@aol.com" <pfjw@aol.com>: Jan 25 04:13AM -0800 > >"I will try to put in the > drop box."   > Too bad. Dropbox doesn't want to display for me. It might be because I used to be a member ad gave it up. I am currently looking for free hosting that is compatible with my browser.   Dropbox does not support Samsung devices for what that is worth. Or so they tell me.   Peter Wieck Melrose Park, PA

rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 08:06AM -0500 >> refers to which direction the log curve goes, a log taper or an exponential >> taper. A linear taper is the same either way... it's linear.   > I would very much expect he didn't need to 'give it a thought' to work out something so obvious.   And yet, he mentions he has never seen a reverse linear taper.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

"pfjw@aol.com" <pfjw@aol.com>: Jan 25 05:22AM -0800 On Thursday, January 25, 2018 at 8:06:29 AM UTC-5, rickman wrote: > And yet, he mentions he has never seen a reverse linear taper.   Back when I was a journeyman electrician, and therefore was privileged to haze the apprentices, I asked one to fetch me (amongst many other things) a combo-plate from the warehouse like this: https://cdn.gescan.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/b/ibv97532-2.jpg   And when he brought me this:   https://images.homedepot-static.com/productImages/5849af02-96ef-4c79-9192-37a8464488aa/svn/stainless-steel-legrand-pass-seymour-combination-wall-plates-sl18cc5-64_1000.jpg   I sent him back, stating I needed the receptacle on the left.   He got as far as the door before he caught on. And it never happened to him again. Others got all the way to the counter at the warehouse.   Peter Wieck Melrose Park, PA

amdx <nojunk@knology.net>: Jan 25 08:00AM -0600 > JB Weld is your best friend. Get a soda-straw or heat-shrink tubing about the same diameter as the shaft, either use the broken piece or a suitable bit of solid material to extend the shaft to the correct length. Mix up the *SLOW* JB Weld epoxy, and use the straw/tubing to hold the shebang together and vertical, but out of the pot, until the epoxy sets up. Let the epoxy fill any voids. The result will be stronger than the original.   > Peter Wieck > Melrose Park, PA   I have repaired many broken plastic parts. I have a kit with 0.025" and 0.035" drill bits and matching steel rods. I put the parts together, then drill through where inserting a steel pin will give it the most strength. I epoxy the joint and the pin and put it all together. I use a Dremel tool to drill the hole and and cut the steel pin off, after the epoxy sets. The epoxy I have is Huntsman Fastweld 10, (ex. Ciba-Geigy Araldite) It is a 5 minute set 24 hour cure.   Mikek

amdx <nojunk@knology.net>: Jan 25 08:15AM -0600 > He got as far as the door before he caught on. And it never happened to him again. Others got all the way to the counter at the warehouse.   > Peter Wieck > Melrose Park, PA   In my late teens a father bought his daughter a Volkswagen Beetle, the first thing he did was send her to go to the gas station* and have them check the water in the radiator.   Mikek   * back when they had service at gas stations.

rickman <gnuarm.deletethisbit@gmail.com>: Jan 24 11:57PM -0500 > On Monday, 22 January 2018 20:56:52 UTC, Terry Schwartz wrote: >> At my last company, I spent the better part of my last 4 or 5 years dealing with water conductivity issues. We produced machines that electrolyzed water into base and acid components in order to produce cleaning chemicals. <<< snip >>> > I'd be interested to find out about the production of the cleaning chemicals.   I can tell you it wasn't from electrolysis of water. That produces hydrogen (H2) and oxygen (O2), not acid and base. Anything else would have to come from additives to the water.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

tabbypurr@gmail.com: Jan 25 12:15AM -0800 On Thursday, 25 January 2018 04:58:09 UTC, rickman wrote:   > I can tell you it wasn't from electrolysis of water. That produces hydrogen > (H2) and oxygen (O2), not acid and base. Anything else would have to come > from additives to the water.   it's saltwater.   I'm curious when this was patented, if it was.     NT

rickman <gnuarm.deletethisbit@gmail.com>: Jan 25 08:11AM -0500 >> (H2) and oxygen (O2), not acid and base. Anything else would have to come >> from additives to the water.   > it's saltwater.   Not really. All water has contaminants. The water he has mentioned was fresh water with more or less contaminants. Still, it wouldn't be described as electrolysis of (salt)water if the interesting part was the contaminants. It would be described as the interesting bits dissolved in water.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

"pfjw@aol.com" <pfjw@aol.com>: Jan 25 05:36AM -0800 Apropos electrolysis and water, way back in the day in high-school, my chemistry teacher showed us how to make Hydrogen peroxide using electrolysis. It was crude and not very efficient, and wasteful of resources.   Today, not so much.   https://link.springer.com/article/10.1023/A%3A1017588221369   Under controlled conditions, other products are also possible. I suspect that is what Tennant was doing.   Side Note: This teacher partnered with several of the history teachers. He had us collect 'night soil' to make gunpowder when we were studying the Civil War, we had to learn the 'secret code' whereby one could identify an American anywhere, any time (this _was_ the 1960s, remember), and we had to learn the ten (10) reindeer. In any case, a lot of very basic and very useful chemistry and applied science has stuck with me over the years.   Peter Wieck Melrose Park, PA

Terry Schwartz <tschw10117@aol.com>: Jan 25 06:06AM -0800 Apparently anyone can be an expert on things they do not understand.

whit3rd <whit3rd@gmail.com>: Jan 24 05:26PM -0800 On Wednesday, January 24, 2018 at 9:18:36 AM UTC-8, KenO wrote:   > A while ago put a number of HDDs in storage.   > Recently tried to use and noticed that some do Not spin up (all were working when put in storage).   > Had read that sometimes the heads will stick or other factors like lube will cause the disk from spinning.   Yes, motor power is sometimes a problem: first thing to do is listen very hard. If it IS spinning, don't hit it... but if it isn't, the motor control will shut down a second after power is applied, so what you want to do is give the drive a brisk twist just after applying power. Set the drive on a horizontal surface, flip on power and quickly rap one corner so as to make the drive twist position slightly... try both directions. You must switch the power off and wait a few seconds between each trial. Give it a dozen tries (use a stick, no sense getting bruised).   Apply heat (hair dryer is fine) to warm the case, wait a few minutes, and try again. You just want the aluminum parts warm so the lubricant softens.   If that doesn't work, examine the drive electronics, sometimes it's just a shorted diode on the power pins. And, sometimes there's a scorched odor and a crater in one of the black plastic rectangles...

tabbypurr@gmail.com: Jan 25 12:11AM -0800 On Thursday, 25 January 2018 00:02:21 UTC, Clifford Heath wrote: > a Fujitsu Eagle hard drive. Pretty difficult; it took two > strong people to coordinate a twist on a 60kg drive without > dropping it.   how many platters did that have?? Even the original 2' wide rusty platter stack didn't come in at 60kg iirc.     NT

tabbypurr@gmail.com: Jan 25 12:14AM -0800 On Thursday, 25 January 2018 08:11:54 UTC, tabby wrote:   > how many platters did that have?? > Even the original 2' wide rusty platter stack didn't come in at 60kg iirc.   > NT   11x 10.5" platters, 4k rpm, 30 second spin-up time.     NT

Clifford Heath <no.spam@please.net>: Jan 25 07:44AM +1100 >> how many platters did that have?? >> Even the original 2' wide rusty platter stack didn't come in at 60kg iirc. > 11x 10.5" platters, 4k rpm, 30 second spin-up time.   I never weighed one, just took a guess. It was a difficult thing to lift and apply power then a rapid rotational jerk to however. Then gently lift it back into the rack to avoid crashing anything. 540MB if I recall - I don't even have a thumb drive that small any more.

jack4747@gmail.com: Jan 25 02:06AM -0800 Il giorno mercoledì 24 gennaio 2018 18:18:36 UTC+1, KenO ha scritto:   > A while ago put a number of HDDs in storage.   > Recently tried to use and noticed that some do Not spin up (all were working when put in storage).   > Had read that sometimes the heads will stick or other factors like lube will cause the disk from spinning.   when the disk is powered off the heads are parked, and if the heads touch the platters then you can throw the HD in the trash.   If it doesn't spin up it's because the bearings of the motor are stuck. A gentle but firm poke on the side of the disk should help. Also putting the HD in vertical instead of horizontal position when it power up may help. Or shaking it a little.   Bye Jack

"Rick" <rike22@bellsouth.net>: Jan 25 05:12AM -0600 "John Robertson" <spam@flippers.com> wrote in message news:mZidnWkj6PCjhvTHnZ2dnUU7-L2dnZ2d@giganews.com... > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."   http://www.alps.com/prod/info/E/PDF/Potentiometer/TAPER.pdf

tabbypurr@gmail.com: Jan 25 03:31AM -0800 On Thursday, 25 January 2018 09:45:34 UTC, Clifford Heath wrote: > Then gently lift it back into the rack to avoid crashing anything. > 540MB if I recall - I don't even have a thumb drive that small any > more.   sounds like an improvement on: 1956 IBM 350. fifty 24-inch (0.6 m) platters, total capacity (3.75 megabytes).     NT

Harold Newton <harold@example.com>: Jan 25 02:50AM On Wed, 24 Jan 2018 09:46:53 -0800, Jeff Liebermann wrote:   > T-Mobile doesn't claim to have service, I have not idea if they will > thank you for improving their footprint, disconnect your service, or > something in between. Good luck.   Hi Jeff, Thanks for that input.   It's not a big deal because I was answering the question for "The Real Bev", where I'm pretty sure (but not positive) the answer is thus.   1. Repater 2. Femtocell   The Repeater "probably" does not report back to the cellular provider anything as it's likely just a "bridge" of sorts that just passes the MAC address (among other things) straight through.   In that case, the cellular provider probably can't tell that you moved the repeater because it likely doesn't even know that the repeater is involved.   The Femtocell is *completely* different.   They know *everything* about the Femtocell; so it's interesting you were able to move it. Perhaps the IP geolocation isn't great enough, in your test, to flag their "movement" algorithm.   Thanks!

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Terry Schwartz <tschw10117@aol.com>: Jan 24 08:59AM -0800 Yes -- I imagine that is true, hence the need for finer control at lower volume levels.   Terry

Terry Schwartz <tschw10117@aol.com>: Jan 24 09:03AM -0800 On Wednesday, January 24, 2018 at 10:59:48 AM UTC-6, Terry Schwartz wrote: > Yes -- I imagine that is true, hence the need for finer control at lower volume levels.   > Terry   Actually, I think the ear responds in an anti-log fashion. Small changes in audio source output levels are perceived as large changes at lower volume levels. Not so much at higher levels, where the ear essentially "saturates" and cant tell the difference between 90dB and 100dB (numbers pulled out of nowhere as examples) So the log curve on the pot compensates for this.

tabbypurr@gmail.com: Jan 24 10:51AM -0800 On Wednesday, 24 January 2018 17:03:50 UTC, Terry Schwartz wrote:   > > Yes -- I imagine that is true, hence the need for finer control at lower volume levels.   > > Terry   > Actually, I think the ear responds in an anti-log fashion. Small changes in audio source output levels are perceived as large changes at lower volume levels. Not so much at higher levels, where the ear essentially "saturates" and cant tell the difference between 90dB and 100dB (numbers pulled out of nowhere as examples) So the log curve on the pot compensates for this.     AIUI log pots were never really log. They normally used 2 resistance zones to give a very crude approximtion of a log law. It was good enough for audio, where the aim was to avoid everything happening down the bottom end of travel.     NT

"Gareth Magennis" <soundserviceleeds@outlook.com>: Jan 24 09:23PM wrote in message news:aa7420bf-47db-4c33-a3f6-2bfd9cb05d88@googlegroups.com...   >"I had a go at rewinding a wire-wound log pot one time, it survived a year and then something went wrong. "   I repaired a variac a while back. Obviously it was linear. Luckily I caught it in time as it was rubbing the wiper over a winding that was popped out of place and it would have broken soon.   But don't confuse a variac with a pot, a variac actually works like a transformer. Now if one were to feed it DC it would be nothing but a pot, and likely burn up unless you kept the input voltage down.   But a little bit of glue took care of it, good thing too as it was one of the ones that go up to 150 VAC.       *************************************       Pah, mine goes to over 260 VAC.       Gareth.

oldschool@tubes.com: Jan 24 03:23PM -0600 On Wed, 24 Jan 2018 06:02:37 -0800 (PST), "pfjw@aol.com" <pfjw@aol.com> wrote:   >but nothing on pots, linear or rotary.   >Peter Wieck >Melrose Park, PA   That's exactly what I found on the web. In other words, NOTHING regarding the K-taper. But I did find the W-taper and it was explained the same as you said. I found some forum where they were discussing pot tapers and some mentioned even more letters, such as N, S, M, D, and a few more. But not K. And yea, I managed to bring up drill bits too. That forum is here: http://www.diystompboxes.com/smfforum/index.php?topic=92918.0   This pot is R60, (master volume control). It's a unusual type of pot in the sense it's mounted to the PCB and mounted backwards, meaning there is a small piece of metal (ring) attached to it's rear, that is soldered to the PCB and the three tabs are bent downward, where they are soldered to the PCB.   I have not yet taken it off the board. The pot does work, but the shaft is broken below the front panel surface. My first thought is to contact Altec Lansing and see if I can get an exact replacement. If not, I may try to saw off the remaining plastic shaft so it's flat, and make up a "sleeve" for it, (a piece of metal tubing) and glue another shaft to it with the tubing to reinforce it. This shaft should be about 1.5 inch long, (before being broken) so I have room to work, since there is still a half inch to work with. If none of that works, I'll have to Mcgyver some other pot in there, and will choose an audio taper type.   With any luck, Altec will have a replacment part. That would be the easiest fix.   A while back, I found out that Peavey electronics does have parts for all their old stuff. I hope Altec Lansing does too.   For reference, there is a lot of useful info about pots on this website. http://www.potentiometers.com/potcomFAQ.cfm?FAQID=29

"pfjw@aol.com" <pfjw@aol.com>: Jan 24 01:34PM -0800 > I have not yet taken it off the board. The pot does work, but the shaft > is broken below the front panel surface.   JB Weld is your best friend. Get a soda-straw or heat-shrink tubing about the same diameter as the shaft, either use the broken piece or a suitable bit of solid material to extend the shaft to the correct length. Mix up the *SLOW* JB Weld epoxy, and use the straw/tubing to hold the shebang together and vertical, but out of the pot, until the epoxy sets up. Let the epoxy fill any voids. The result will be stronger than the original.   Peter Wieck Melrose Park, PA

oldschool@tubes.com: Jan 24 03:39PM -0600 On Wed, 24 Jan 2018 05:48:52 -0800 (PST), Terry Schwartz >back of the pot, without sacrificing low level volume control. The switch often > requires a 15 or 20 degree rotation in order to activate -- using up part of the > pot travel.     This is something I never even thought about, but it makes a lot of sense. I recall buying replacment pots for old tube gear, some 45 or more years ago, and you bought them without a switch, and bought the switch separately, which then attached to the rear of the pot. Apparently those pots were made to be used with a switch, but also worked without one. I never noticed any "dead spots" on them, or had problems where I could not turn the volume down low enough. Apparently that was all taken into consideration when they were made. But back then, it was a lot simpler. You chose audio and linear taper, and the correct resistance, and shaft length. That was about it. I recall getting many with LONG shafts that had to be sawed off and a flat spot filed onto the shaft.   The good thing back then is that the shafts were all metal and did not break off.

bruce2bowser@gmail.com: Jan 24 02:03PM -0800 > > You probably have, in instrumentation somewhere. Just not marked as such. Like the intensity control of a scope or some shit like that. I could see there being applications like that. And some things just give you a part number and that's it.   > > I do bet they're rare though.   > What you been smokin?   Have you ever dipped the tip of a cigarette in gasoline and tried it?

Phil Allison <pallison49@gmail.com>: Jan 24 02:34PM -0800 Terry Schwartz wrote:   ------------------------   > Actually, I think the ear responds in an anti-log fashion. Small changes > in audio source output levels are perceived as large changes at lower > volume levels.   ** Like other senses, hearing responds to *percentage" changes in sound level.   The ideal volume control produces similar percentage changes for similar rotations or small movements. Good "log" pots have three linear sections that approximate the ideal fairly well.     .... Phil

jurb6006@gmail.com: Jan 24 03:15PM -0800 >"Pah, mine goes to over 260 VAC. "   Don't try to pull that cotton/polyesther wool substitute over my eyes. Your nominal line voltage is 240. So that means it is like me having one that goes to 130. Yours would have to go to 150 to be equivalent.   What impresses me (some) is how some of these modern power supplies can handle auto-swicthing between line voltages.

MOP CAP <email@domain.com>: Jan 24 04:28PM -0800 As soon as my son teaches me how to scan on my new printer, I will post an old catalog page with many tapers shown. I will try to put in the drop box. I think the page was from an old Centralab catalog. CP

KenO <kenitholson@yahoo.com>: Jan 24 09:18AM -0800 Hi,   A while ago put a number of HDDs in storage.   Recently tried to use and noticed that some do Not spin up (all were working when put in storage).   Had read that sometimes the heads will stick or other factors like lube will cause the disk from spinning.   Did some searching and found   https://groups.google.com/forum/#!searchin/sci.electronics.repair/how$20test$20no$20spin$20hard$20drives%7Csort:date/sci.electronics.repair/WH68qfkAAfM/51WIPwZL8yMJ   https://groups.google.com/forum/#!searchin/sci.electronics.repair/how$20test$20no$20spin$20hard$20drives%7Csort:date/sci.electronics.repair/CDnXwrweST0/6_Sr72pRKUsJ   for specific HDDs but to date No general info on what to test.   Googled using how test "Hard drives" got a lot of hits but nothing helpful to no spin testing to date.   Then decided to try http://www.repairfaq.org and searched with how test "Hard drives" but only got "The Drexel mirror site of the Sci.Electronics.Repair FAQ is temporarily unavailable..."   Appreciate any suggestions   Ken

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Jan 24 07:09PM +0100 On 24-1-2018 18:18, KenO wrote:   > Then decided to try http://www.repairfaq.org and searched with how test "Hard drives" but only got "The Drexel mirror site of the Sci.Electronics.Repair FAQ is temporarily unavailable..."   > Appreciate any suggestions   > Ken   I have "repaired"an old DOS computer with a stuck harddisk. Just gave the case a hard jerk around. It worked. Then made a backup............(it was not MY computer).   So give the HD a gentle slam to rotate it and see if it works. If not slam some more. The disk might wake up.   Do this in off state, then test.

"pfjw@aol.com" <pfjw@aol.com>: Jan 24 10:30AM -0800 Or as my old carpenter foreman used to say:   When in doubt, get a bigger hammer!   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Jan 24 10:54AM -0800 On Wednesday, 24 January 2018 17:18:36 UTC, KenO wrote:   > Then decided to try http://www.repairfaq.org and searched with how test "Hard drives" but only got "The Drexel mirror site of the Sci.Electronics.Repair FAQ is temporarily unavailable..."   > Appreciate any suggestions   > Ken   This problem was fairly common when HDDs first went down to 3.5" form factor. The standard solution was to plastic bag them and freeze them.   If the head's glued to the disc surface, slamming it's likely to rip the head off. It's a last resort option only.     NT

"pfjw@aol.com" <pfjw@aol.com>: Jan 24 11:13AM -0800 If the alternative is landfill, many alternate means-and-methods open up.   Peter Wieck Melrose Park, PA

"Ian Field" <gangprobing.alien1@virginmedia.com>: Jan 24 08:07PM <tabbypurr@gmail.com> wrote in message news:6e1f60bd-8a8c-4afb-bc24-e51f99b2eef5@googlegroups.com... > factor. The standard solution was to plastic bag them and freeze them.   > If the head's glued to the disc surface, slamming it's likely to rip the > head off. It's a last resort option only.   Ripping stuck stuck heads off wasn't very unusual with old drives that had exposed flywheel on the spindle motor. back in the days of head steppers - you could sometimes get at that too.   Never tried putting one in the fridge, but it sounds less likely to do damage - if that doesn't work; resort to violence. Clonking it on the desk might free it - too little wont free it, too much might shift coating off the platters. some drives sense failure to spin up and pulse the head servo to try and free it - careful timing when you clonk it might add that little bit extra that helps the drive fix itself.

The Real Bev <bashley101@gmail.com>: Jan 24 12:10PM -0800 Worst case: give them to the children to disassemble for the magnets. You need a REALLY tiny Phillips for the last screws.   -- Cheers, Bev If trees could scream, would we be so cavalier about cutting them down? We might, if they screamed all the time, for no good reason. - Jack Handy

Pat <pat@nospam.us>: Jan 24 03:20PM -0500 On Wed, 24 Jan 2018 20:07:07 -0000, "Ian Field" >the platters. some drives sense failure to spin up and pulse the head servo >to try and free it - careful timing when you clonk it might add that little >bit extra that helps the drive fix itself.   I always tried a mechanical fix BUT NOT slamming them down or hammering on them. Rotate them! If you hold them with your fingers on the sides and rotate them as quickly as you can, the mass of the platters tries to keep them stationary while you rotate the case. I haven't tried that in years since I haven't needed to, but it used to work.

Mike_Duffy <mqduffy001@bell.net>: Jan 24 03:58PM -0500 On Wed, 24 Jan 2018 15:20:00 -0500, Pat wrote:   > I always tried a mechanical fix BUT NOT slamming them down or > hammering on them. Rotate them! If you hold them with your fingers > on the sides and rotate them as quickly as you can,   Agree. If you want to augment the torque by a few orders of magnitude, get a flat sanding attachment for a drill and duct tape the disk to the attachment. You should be able to quite accurately guess the position of the main axis by looking at the housing; if not find the model# on the web and look for a service document with a cutaway view.   Presuming your drill is reversable, you can easily alternate the torque between successive trigger pulls if the drill is clamped. The goal is not to spin it fast; rather to quickly cause it to reverse direction.

dplatt@coop.radagast.org (Dave Platt): Jan 24 01:40PM -0800 In article <gbqh6dd69pkn29i6icke6r32cg1ij6jlu5@4ax.com>, >platters tries to keep them stationary while you rotate the case. I >haven't tried that in years since I haven't needed to, but it used to >work.   +1 to this. It worked well enough for me, years ago, that I was able to do some data rescue from a couple of drives which declined to spin up on their own after sitting idle for a year or two.

John Robertson <spam@flippers.com>: Jan 24 03:48PM -0800 On 2018/01/24 1:40 PM, Dave Platt wrote:   > +1 to this. It worked well enough for me, years ago, that I was able > to do some data rescue from a couple of drives which declined to spin > up on their own after sitting idle for a year or two.   "Shake & Bake" were the methods used to get stuck drives to spin up in the 80s. The shake was a twist as described, the bake was to warm the unit to around 100C to soften the lubes...and then you immediately sucked the data off and trashed the sick drive.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

philo <philo@privacy.net>: Jan 24 05:54PM -0600 > When in doubt, get a bigger hammer!   > Peter Wieck > Melrose Park, PA   Had an MFM drive I got to work by standing on end.     If a "jerk" does not do the trick on an ATA drive I've also opened them up and gentry nudged the arm.   Back up at once as the drive will not function long

Clifford Heath <no.spam@please.net>: Jan 24 10:01PM +1100 On 25/01/18 08:40, Dave Platt wrote:   > +1 to this. It worked well enough for me, years ago, that I was able > to do some data rescue from a couple of drives which declined to spin > up on their own after sitting idle for a year or two.   Around 1992 we had to do that (after each power failure) on a Fujitsu Eagle hard drive. Pretty difficult; it took two strong people to coordinate a twist on a 60kg drive without dropping it.

Jeff Liebermann <jeffl@cruzio.com>: Jan 24 09:46AM -0800 On Tue, 23 Jan 2018 17:44:12 +0000 (UTC), Harold Newton   >Theoretical question: >Q: How would T-Mobile *know* if I *moved* the femtocell and/or repeater to >a different location altogether than my own house?   You do the grunt work this time. Dig into the instructions for the Femtocell box and see if it has a GPS inside. If it's not clear, grab the FCCID and look it up on the FCCID site. If it has a GPS, T-Mobile will know where you're located. Whether they do anything about a change in location is unknown. I've moved a Verizon femtocell box about 50 miles without any problems. However, that was inside Verizon territory. If you move your T-Mobile femtocell to some location where T-Mobile doesn't claim to have service, I have not idea if they will thank you for improving their footprint, disconnect your service, or something in between. Good luck.   -- 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

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