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mogulah@hotmail.com: Dec 10 12:55PM -0800 On Saturday, December 5, 2015 at 4:30:21 PM UTC-5, Chuck wrote: > amplifiers with wrong value resistors at various locations. The > first one was a bear because I had never seen a Japanese company > make that kind of mistake.   Lawsuits over the years have shown their companies to be just as liable occasionally, too (like with Nomura, Sumitomo, Mitsubishi, Toyota, Honda, Mazda, Hitachi and others...) I think that things are done less purposely with regards to American markets, though.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 10 04:02PM -0500 <mogulah@hotmail.com> wrote in message news:0d1e8a73-0190-4762-8391-6d19e0320d2d@googlegroups.com... On Saturday, December 5, 2015 at 4:30:21 PM UTC-5, Chuck wrote: > >parts from the stock room, onto a protoboard like breadboard.   > >My lab partners and I were experienced hams and got ours working in no > >time , no problems.   At college I had a lab with the same thing. We designed simple circuits and built them and took measurments on them. There were boxes of parts that were suspose to be the same parts. Some of the parts were either bad or out of spec. Not on purpose, they just got that way over the years. Me and a person I was with usually could locate the bad parts and get our project going first. Got to be a joke that the ones that got theirs to work had the lucky box with all good parts for that design.

mroberds@att.net: Dec 11 07:41AM > Maybe we could share some "war stories" of cool repairs we have done > in the past.   It's definitely not consumer electronics, but here goes.   I used to work at a company that made flight simulators. My official job was writing code to make the navigation instruments display correctly, according to the simulated position of the aircraft, which frequencies the radios were tuned to, the position of circuit breakers, etc.   Some of the laws of nature at that particular job included:   1) Techs string wire.   2) Programmers write programs.   3) Techs never make mistakes when stringing wires.   4) No programmer could ever possibly understand the intricacies of stringing wires. Therefore, any complaints by programmers about the wiring can usually be disregarded.   5) Any persistent complaints about the wiring can be remedied by telling the programmers to work around it in the code.   Never being one to obey the laws of nature, I brought in my own meter and checked things out when the sim didn't seem to work right. My boss knew that I had something of a clue; I had been giving "how to read a schematic" lessons to a few of my cow-orkers (in software) who were also new hires or just wanted to know how. He basically told me that he didn't mind me doing my own checks as long as I was careful with the sim hardware, and that I should expect the techs to get mad at me if they ever saw me doing it.   I couldn't get the right DME indicator to light up in one sim. (It was a box in the instrument panel with three 7-segment displays and a couple of buttons. It was supposed to display how far the airplane was from a particular radio station.) After a few rudimentary checks of my code, I wrote up a "right DME inop" trouble ticket. The technician wrote back, "Wiring checks to print, DME sent for repair". Sure enough, there was a hole in the panel. When it was again filled, I tried again...no joy. I swapped the left and right indicators - hmm, the problem stayed with the socket instead of following the indicator. I broke out the wiring diagram and my own personal multimeter and started chasing around behind the panel - no wires or pins for power on the right DME socket. (It was something like a DB25 or DB37, with individual "crimp and poke" contacts.) I dutifully re-opened the ticket, and the tech dutifully wrote "wiring checks to print" and closed it again.   About this time, the sim was shipped to the site, even though it was broken. The standard process was to completely build the sim at the factory, test it out, ship it to the site, certify it, and put it in revenue service. For sites that were far away from the factory, this practice was generally followed, because it was expensive to ship people to site to finish working on the sim. However, the site that was closest to the factory (~3 hr drive) was notorious for the following:   Factory: We will have the sim done on $DATE.   Site: No no no! We've already sold time on that sim to customers on $DATE-30days and we can't reschedule! We *must* have it here sooner!   Factory: Why did you do that? The sim will not be done on $DATE-30days. It will be broken and unusable for training.   Site: We don't care.   Factory: If we ship it at that time, it will suck.   Site: We don't care!!! Ship it shipit SHIPIT!!1!   Factory: <sigh> OK.   (time passes) Site: Well you got the sim to us on time but it sucks! Everything's broken and we can't put the customers on it! Fix it fixit FIXIT!!1!   Factory: <sighs deeply, starts phoning rental car agencies and hotels>   So I get to the site and the site manager is bugging me about the right DME indicator. I walk in to the site maintenance shop and tell the techs there I need some connector pins, the crimper tool, some wire, and a bench power supply. They are extremely wary of this as they have experienced "programmers with screwdrivers" before, but they give me the requested items and follow me into the sim, probably in hopes that my body will shake and jerk in interesting ways as I electrocute myself. I put the pins on the wires and put them in the (still vacant) slots on the right DME connector. Wires run out under the panel to the power supply, which temporarily gets the co-pilot's seat. Fire up the sim, hit the power supply, and whaddayaknow - DME love for all. I disappointed the techs, but the site manager was very happy.   I pointed out the relevant page in the wiring diagram book, so the site techs could get it wired in correctly. I figured they had a lot more experience than I did in fixing factory screwups. They were satisfied with this, and I got to go home.   Matt Roberds

Mike Tomlinson <mike@jasper.org.uk>: Dec 11 08:43AM > Site: Well you got the sim to us on time but it sucks! Everything's > broken and we can't put the customers on it! Fix it fixit > FIXIT!!1!   Why does that sound so horribly, horribly familiar?   Brrr. Memories I'd rather forget.   -- (\_/) Tyson Fury: #homophobe #bigot #throwback #missinglink (='.'=) #neanderthal #misogynist #redneck #dickhead (")_(")

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 11 05:27AM -0600 <mroberds@att.net> wrote in message news:n4dume$d8b$1@dont-email.me... > experience than I did in fixing factory screwups. They were satisfied > with this, and I got to go home.   > Matt Roberds   Wow. Lots of times I'm too lazy to read to the end - but this was great! Loved it!   mz

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Dec 11 06:02AM -0600 How about another slant on "War Stories" ?   The least competent, most alcoholic, etc tech person you ever had to work with or follow after they got fired?   When I was first starting in consumer electronics repair, (my first job in the business, actually) I was hired to replace "Karl". He had a resume - in the '70s a well respected shop paid for him to come over from Germany.   By my time however - apparently a broken down alcoholic.   He would "repair" tons of stuff, bill out huge amounts (paid on commision) then abscond when the re-do's became too much.   I was charged with fixing his re-do's and generally cleaning up the chaos he had left behind.   Next job - another shop. They had just fired the SAME GUY. Same situation. Re-do's coming in one after another. Angry customers. Piles of screws and small hardware in a pile on one corner of the bench. Dis-assembled units all over the place, and I mean ALL OVER. A Teac A-4010 in about four different parts of the shop. No pressure... I'd never even seen one before.   Next job - SAME DEAL. By now I was getting pretty good at reverse-engineering other peoples screw-ups, but - really?   A couple examples:   Auto-reverse car cassette deck. He didn't have the correct drive belt, so he had SUPER-GLUED the ends of the old belt together. Played about 2 mnutes, if that.   A Marantz 1060 integrated amp (re-do) with a blown channel. He had substuted a driver transistors with a similar package item. Unfortunately, the part he used was a VOLTAGE REGULATOR IC and not even a transistor.   He had his "groupies" though. Some customers followed him from one job to the next.   About 1987 Bang & Olufsen in Chicago contacted our shop for a reference on this guy.   We were rolling on the floor!   Gave him an absolutely GLOWING reference. We could think of nothing funnier than the prospect of this guy working for B&O.   (no he didn't get hired)     Good times.

Chuck <chuck@mydeja.net>: Dec 11 10:46AM -0600 On Fri, 11 Dec 2015 06:02:13 -0600, "Mark Zacharias" >than the prospect of this guy working for B&O.   >(no he didn't get hired)   >Good times. Mark,   In the early 70s there was a company that sold strips of rubber of various sizes with a razor blade, jig and a tube of super glue that was supposed to be used to make belts for consumer electronics equipment. I had never seen super glue before so I tried it. Once.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Dec 11 12:09AM -0500 have an 18V 2.4AH battery pack for Ryobi power tools that will no longer take a charge and that the charger indicates is defective.   I've taken it apart and found that it has five pairs of cells that are labeled:   "LS IMR-18650BB YT0288.<different numbers on the ones I can see> Made in China"   I see on line numerous variants of the 18650 cells with various mAH ratings but nothing with the "BB" suffix.   Four of the pairs of paralleled cells show a voltage of 4.1x; the other pair shows 2.1mV.   Is it worth the effort of trying to replace the defective pair, or is there a way that I could try to restore them to life?   If I want to replace the defective pair, I assume that any 18650 cells with at least 1200mAH capacity will work -- but in fact I don't see any that low.   I don't have a spot-welder. If I use a Dremel cutting wheel to cut the tabs on the defective pair, would it be OK to solder new ones in place using copper flashing?   Perce

Clifford Heath <no.spam@please.net>: Dec 11 12:22AM +1100 On 11/12/15 16:09, Percival P. Cassidy wrote: > I've taken it apart and found that it has five pairs of cells that are > labeled:   > "LS IMR-18650BB   18650 is the physical geometry: 18mm diameter, 65mm long, 0=round.   Any Li-ion 3.7V 18650 will do as a replacement (peak charge voltage 4.2V) - but get a matched set of 5.   > I see on line numerous variants of the 18650 cells with various mAH > ratings but nothing with the "BB" suffix.   It's meaningless as far as you're concerned.   > Is it worth the effort of trying to replace the defective pair, or is > there a way that I could try to restore them to life?   No. Replace the lot - you don't want a mis-matched string.   > I don't have a spot-welder. If I use a Dremel cutting wheel to cut the > tabs on the defective pair, would it be OK to solder new ones in place > using copper flashing?   Buy replacements with tabs on. Soldering can damage the cell internally unless you're very skillful and swift.   Avoid Ultrafire and other *fire Chinese brands and their Chinese clones (often repackaged dead cells). They make fantastical claims of capacity, but you're lucky if you get 1000mAH, and never as much as 2000mAH (they often claim 4000 or 6000; no-one can build that).   If you can afford it, buy Panasonic NCR cells - about $12-$15/ea - which if genuine will produce about 3400mAH at a much better sustained voltage. Chalk and cheese against the Chinese cells.   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: Dec 10 09:51PM -0800 On Fri, 11 Dec 2015 00:09:14 -0500, "Percival P. Cassidy"   > have an 18V 2.4AH battery pack for Ryobi power tools that will no >longer take a charge and that the charger indicates is defective.   I totally agree with Clifford Heath. However, let me add a few additional comments.   >I don't have a spot-welder. If I use a Dremel cutting wheel to cut the >tabs on the defective pair, would it be OK to solder new ones in place >using copper flashing?   The cases on most 18650 cells are stainless steel. You won't be able to solder to those. Copper flashing might make a connection, but at the high currents involved, will probably give you intermittent connections, corrosion, or heating problems. Spot weld or forget it.   You can buy 18650 cells with tabs that can be soldered: <https://www.google.com/#q=18650+with+tabs>   I do something different, which might be of interest. Instead of using 18650 cells, I use flat cells usually used in model airplanes, cars, quadcopters, etc. Something like this: <http://www.hobbyking.com/hobbyking/store/uh_listCategoriesAndProducts.asp?cwhl=US&idCategory=86&v=&sortlist=P&LiPoConfig=5&CatSortOrder=asc> The listing are for 5 cell batteries (5S), west coast warehouse, and sorted by ascending prices. If you're lucky, you can find a 5S battery pile that will fit in your Ryobi battery box. If not, you can bash a big hole in the battery pack and improvise.   Note that all the batteries have a "balance charger" connector. I won't go into detail now, but basically this is the way you avoid killing a battery pack. Each cell is monitored individually with no risk of overcharging any of them if another cell is low voltage. <https://www.google.com/search?q=balance+charger> The technique is SLOOOOOWLY creeping into the power tool biz. <https://en.wikipedia.org/wiki/Battery_balancing>   If you decide to go this route, bug me as there are a few other things that you'll need (power connector/adapter, balance charger, etc).       -- 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

mike <ham789@netzero.net>: Dec 10 10:11PM -0800 On 12/10/2015 9:09 PM, Percival P. Cassidy wrote: > YT0288.<different numbers on the ones I can see> Made in China"   > I see on line numerous variants of the 18650 cells with various mAH > ratings but nothing with the "BB" suffix.   There are many variants of cells. The ones designed for high current have lower capacity. If you try to use laptop high capacity cells in a drill, you'll have low performance and short service life. You're likely to find that the correct cells you need cost about the same as a new pack. > pair shows 2.1mV.   > Is it worth the effort of trying to replace the defective pair, or is > there a way that I could try to restore them to life?   You can try to charge the dead pair with a 4V power supply current limited to 100 ma or so. Always wear eye protection! Don't get in a hurry, or you may set the thing afire. Do it in the garage in a bucket that can't burn if the cells catch fire or explode. I've had limited success with that in laptop packs. But don't get your hopes up. If it works, charge each pair individually to the same voltage. Don't get in a hurry, it may take a long time for the current to drop.   > If I want to replace the defective pair, I assume that any 18650 cells > with at least 1200mAH capacity will work -- but in fact I don't see any > that low. NO, get the right type of HIGH current cells and replace them all.   > I don't have a spot-welder. If I use a Dremel cutting wheel to cut the > tabs on the defective pair, would it be OK to solder new ones in place > using copper flashing? DO NOT SOLDER DIRECTLY TO ANY CELL OF ANY KIND. You can solder tabs together, if you're quick about it.   > Perce What's your objective? If you want to play with battery packs, you're on the right path. If you want to drill holes reliably, call up Ryobi and buy a new pack. Last year at this time they all seemed to have lifetime battery guarantee.

mroberds@att.net: Dec 11 08:01AM > I have an 18V 2.4AH battery pack for Ryobi power tools that will no > longer take a charge and that the charger indicates is defective.   If you're in the US, you might check with your local Batteries Plus store. I had some DeWalt 12 V NiCd packs rebuilt by them for pretty reasonable money, a couple of years ago. They have cells with tabs, and the spot-welder to correctly join the tabs together.   Home Depot sells a brand new Ryobi P105 battery - probably the same one you have - for $59+tax. That listing also claims that the battery has a 3-year warranty; is it possible that your battery is younger than that?   Standard disclaimers apply: I don't get money or other consideration from any companies mentioned.   Matt Roberds

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Dec 11 11:05AM -0500 On 12/10/2015 08:22 AM, Clifford Heath wrote:     > 18650 is the physical geometry: 18mm diameter, 65mm long, 0=round.   > Any Li-ion 3.7V 18650 will do as a replacement (peak charge voltage > 4.2V) - but get a matched set of 5.   If I have to get a matched set -- of ten (five *pairs*) -- rather than of two, I might as well get two 4AH ones for $99.     >> Is it worth the effort of trying to replace the defective pair, or is >> there a way that I could try to restore them to life?   > No. Replace the lot - you don't want a mis-matched string.   See above.

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Dec 11 11:13AM -0500 On 12/11/2015 12:51 AM, Jeff Liebermann wrote:   > <https://www.google.com/search?q=balance+charger> > The technique is SLOOOOOWLY creeping into the power tool biz. > <https://en.wikipedia.org/wiki/Battery_balancing>   This battery pack does have connections from every between-cells connection to the PC board, so I am assuming that this was supposed to be part of the balancing circuitry.   I can buy two of the 4AH packs for $99, so replacing all ten cells (five *pairs*) in the present one would probably cost about the same for less capacity as one new one.   Perce

mogulah@hotmail.com: Dec 10 12:43PM -0800 I guess bar-b-que, burgers, fried chicken and french fries are great, but not if you are wearing a buttoned-up shirt that day. So, if you have to eat lunch with a client and other contractors in a diverse environment, what would you recommend? I remember I was watching Seinfeld and somebody ordered chicken or tuna fish salad. Yeah, that's something I could agree with... especially with lettuce, tomato, mayonnaise on well-done toast, with plenty of black pepper and a pickle slice and a cup of coffee. That would seem less "trashier" than slobbering over friend chicken, bar-b-que and coke, right?

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 10 04:55PM -0500 > and a pickle slice and a cup of coffee. That would seem less > "trashier" than slobbering over friend chicken, bar-b-que and coke, > right?   Depends on how big your belly is. If I lean forward just a little, I don't get any food on my clothes regardless of how messy it is. Maybe twirling spaghetti, but french fries? Seriously?   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

x@nospam.com: Dec 10 02:48PM -0800 Phil Hobbs wrote: > twirling spaghetti, but french fries? Seriously?   > Cheers   > Phil Hobbs   How unAmerican that you do not smother your fries in ketchup! lol       --- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 10 07:14PM -0500 >> Cheers   >> Phil Hobbs   > How unAmerican that you do not smother your fries in ketchup! lol   Well, I'm not an American, though I've lived here for a day or two.   And fries with ketchup is a lot less messy than spaghetti with red sauce, unless your gut is so large that you don't have a lap.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics   160 North State Road #203 Briarcliff Manor NY 10510   hobbs at electrooptical dot net http://electrooptical.net

Jeff Liebermann <jeffl@cruzio.com>: Dec 10 04:17PM -0800 >I guess bar-b-que, burgers, fried chicken and french fries are >great, but not if you are wearing a buttoned-up shirt that day.   Wear a bib: <https://www.google.com/search?q=adult+bib&tbm=isch> Form follows function.   -- 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

Cydrome Leader <presence@MUNGEpanix.com>: Dec 11 12:52AM > I guess bar-b-que, burgers, fried chicken and french fries are great, but not if you are wearing a buttoned-up shirt that day. So, if you have to eat lunch with a client and other contractors in a diverse environment, what would you recommend? > I remember I was watching Seinfeld and somebody ordered chicken or tuna fish salad. Yeah, that's something I could agree with... especially with lettuce, tomato, mayonnaise on well-done toast, with plenty of black pepper and a pickle slice and a cup of coffee. That would seem less "trashier" than slobbering over friend chicken, bar-b-que and coke, right?   If your are known for anything "good"?   Had one repair guy drive from Michican to Chicago for a single service call. He seemed keen on getting an Italian Beef (It's a Chicago-area sandwich nobody outside the area can get right for some reason). He just wanted to know what place to try.   It's something I take for granted, but they're a big deal for visitors.

jeff.shen.hall@gmail.com: Dec 10 09:58AM -0800 On Saturday, June 26, 2010 at 1:40:44 AM UTC-4, Allyn Oldfield wrote: > a couple of screws- good as new!   > Cheers > Allyn   I also had a bad power switch on a GTP-450. It measured 275K ohms across what should have been open terminals. New switch fixed the problem.   Jeff

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