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"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 27 05:03PM -0400 > > it looks the same size black lump and the connector pushes in, so it > > must be ok .   > Once upon a time, there was movement to color-code and size-code these things... It never quite took.     Have you seen these adapters?   http://www.ebay.com/itm/171829811403

"pfjw@aol.com" <pfjw@aol.com>: Mar 27 04:00PM -0700 On Sunday, March 27, 2016 at 5:03:32 PM UTC-4, Michael Terrell wrote:   > > Once upon a time, there was movement to color-code and size-code these things... It never quite took.   > Have you seen these adapters?   > http://www.ebay.com/itm/171829811403   I have. Sadly, it was the south end where the color-coding never took, not the north end.   Peter Wieck Melrose Park, PA

Cydrome Leader <presence@MUNGEpanix.com>: Mar 28 03:58PM > I would actually like to have a switch on the front panel of an amp to switch the pre out/main in loop rather than their jumpers. Too easy to lose.   > And then my buddy got this Marantz, a really nice one, 2325. It has the type of jack where you plug something in and it breaks the connection. I'd much rather have a switch, even if it is on the back and many of them are.   > Another thing I noticed about those shunts is ain't none of the MFs ever the same size. I have had a drawerfull of them and still had to make shunts out of 12 gauge wire because none of them fit.   When would you use a diferent preamp, or different power amp in an integrated unit anyways? Anything with the shunts was already packed with all sorts of silly inputs to start with.

Cydrome Leader <presence@MUNGEpanix.com>: Mar 28 04:20PM > test procedure for all the old 1970s Marantz amps, was to throw a short > circuit across the outputs. If it didn't survive, it would not be given > back to the owner (until it did).   It is sort of sad it can't handle that. Just a few warranty service calls would pay for hundreds or thousands of fuse to have been installed.

T i m <news@spaced.me.uk>: Mar 28 03:40PM +0100 On Sat, 26 Mar 2016 19:06:00 -0500, M Philbrook <jamie_ka1lpa@charter.net> wrote:   <snip>   FWIW, I've just desoldered the legs of the power FETs, tacked short wires into them and plugged them into my little component tester. I'd say the results suggest they are ok?   (Looking at the FETs left to right):   https://dl.dropboxusercontent.com/u/5772409/FET%20board.jpg https://dl.dropboxusercontent.com/u/5772409/FET%201.jpg https://dl.dropboxusercontent.com/u/5772409/FET%202.jpg https://dl.dropboxusercontent.com/u/5772409/FET%203.jpg https://dl.dropboxusercontent.com/u/5772409/FET%204.jpg     > That driver board has a lot of bad solder joints on it...   Again, when I de-soldered them they looked ok so it may have just been a camera thing.   >Use loup if you have one put some clean solder on the joints where > the power fets are especially.   Whilst some of the joints look a bit 'iffy' under the loup, I think they are just that and are making electrical connection. The worst seem to be post manufacturer 'mods' rather than straight manufacturing faults.   I have found a generic BMS board on eBay that looks compatible so in light of the FET test (assuming the test means anything) I might just give one of those a go.   Cheers, T i m

"Ralph Mowery" <rmowery28146@earthlink.net>: Mar 28 10:59AM -0400 "T i m" <news@spaced.me.uk> wrote in message news:9nfifb1ete4av4j64ah44j73rs0ac3mba3@4ax.com... > https://dl.dropboxusercontent.com/u/5772409/FET%202.jpg > https://dl.dropboxusercontent.com/u/5772409/FET%203.jpg > https://dl.dropboxusercontent.com/u/5772409/FET%204.jpg   The 2 nd from the right To-220 looking FET seems to be shorter than the others. As the back of the FET is the 3 rd leg should it have a wire connecting to that long pad above it ?

T i m <news@spaced.me.uk>: Mar 28 05:19PM +0100 On Mon, 28 Mar 2016 10:59:19 -0400, "Ralph Mowery"   >The 2 nd from the right To-220 looking FET seems to be shorter than the >others. As the back of the FET is the 3 rd leg should it have a wire >connecting to that long pad above it ?   Well spotted (and thanks for looking etc) but for some reason there is no tag on that FET but the whole back was soldered to what I think is the ground at the back.   In fact, I desoldered the tag on the right hand FET and the two leads from the pads but it was still stuck solid. It seems there are two soldered areas under the FETs, one under the tag and one right underneath.   Whilst de-soldering the 3rd FET it came off the board completely.   Cheers, T i m

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 27 04:56PM -0400 > Eveready or Duracell, either will replace the unit at no cost. Chinese crap, no. Fluke would call that negligence, and rightly so.     Peter, the Fluke meters that I've repaired all had GE labeled NiCads. They were assembled in the form of two packs of two cells that were soldered together in a pair, and they used some Berg terminals that snapped onto tiny ball tipped terminal posts. They were approximately C cell sized, and each pair was in a snap on cover, one on each side of the line transformer. I have located a supply of new cells from another OEM, but the wires are hard as a rock, and most of the terminals ar damaged in the latest batch of Fluke 8050 meters that I received. I have been unable to locate the part number for the terminals. It isn't listed in the Fluke manuals. We used that terminal at Microdyne, but I no longer have any contacts there now that it is part of L3-Com, in Philly. As far as I know, they dropped support for every product that used that terminal, as well.

"pfjw@aol.com" <pfjw@aol.com>: Mar 27 03:58PM -0700 On Sunday, March 27, 2016 at 4:57:07 PM UTC-4, Michael Terrell wrote: > longer have any contacts there now that it is part of L3-Com, in Philly. > As far as I know, they dropped support for every product that used that > terminal, as well.   Send them to Fluke. Betcha you will be pleasantly surprised.   Peter Wieck Melrose Park, PA

John Robertson <spam@flippers.com>: Mar 27 04:35PM -0700 > Just keep this in mind.   > Peter Wieck > Melrose Park, PA   Lifetime by Fluke is defined as seven years after they stop production of the device:   http://en-us.fluke.com/support/warranties/   My 1980s vintage Fluke test gear 9100s, 9010s, etc., is long past their lifetime warranty.   John ;-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Cydrome Leader <presence@MUNGEpanix.com>: Mar 28 03:48PM > RF/AF Signal Injector > Micro Maglite > 3D Maglite (AKA "Persuader")   Be extra careful with the maglights. Leaked battery swell up and the juice that comes out will corrode the aluminum and constrict around the battery. It can be impossible to get the batteries out. I had a Kel-Lite destroyed that way. Somebody on usenet suggested wrapping the cells in saran wrap so if they leak you can just slide the whole mess out.

"dangerous dan" <dangerous@dan.com>: Mar 27 05:39PM -0500 While looking around the storage building, I found an old 12 volt VCR, dot matrix printer, wiring harness for an old GE classic 2 mobile phone, from before cell phones existed. This stuff was considered high tech. Many years ago I'd be on location in the oil field, watching TV and videos, talking on the mobile phone.   I had to manually switch towers on the phone, depending on what area I was in.   Now on my smart phone I can watch videos, make phone calls, listen to the radio, surf the internet. It holds 7 gigs of music, and much more in videos. This one device can do so many things it took many other things to do.   In the house I've shrink wrapped a turntable, amplifier, another VCR, two old cband satellite receivers. There are at least a dozen VCR tapes. I don't know what I'll ever do with these things.   It makes me a little sad and nostalgic.   In twenty years I wonder what changes have made today's high tech obsolete?

jurb6006@gmail.com: Mar 28 03:09AM -0700 I kinda hope you don't have a CCW...   It is nice to have old things, but not to shrink wrap them.

"dangerous dan" <dangerous@dan.com>: Mar 28 07:31AM -0500 > I kinda hope you don't have a CCW... > It is nice to have old things, but not to shrink wrap them.   CCW? What does that stand for?   http://acronyms.thefreedictionary.com/CCW

MJC <gravity@mjcoon.plus.com>: Mar 28 02:00PM +0100 In article <mLadnQ6HccyMuWTLnZ2dnUU7-KvNnZ2d@giganews.com>, dangerous@dan.com says... > > It is nice to have old things, but not to shrink wrap them.   > CCW? What does that stand for?   > http://acronyms.thefreedictionary.com/CCW   Counterclockwise (widdershins) was at the top of my interpretations too...   Mike.

John Larkin <jjlarkin@highlandtechnology.com>: Mar 27 10:20AM -0700 On Sat, 26 Mar 2016 19:56:12 +0000 (UTC), Andre Majorel >> a soldering iron tip.   >News to me. In what way are multi-layer ceramic caps and >soldering irons incompatible ?   Not a bit.     --   John Larkin Highland Technology, Inc   lunatic fringe electronics

Jon Elson <elson@pico-systems.com>: Mar 27 10:45PM -0500 Andre Majorel wrote:   >> a soldering iron tip.   > News to me. In what way are multi-layer ceramic caps and > soldering irons incompatible ?   Really, before I got my pick and place machine, I hand-soldered about 25,000 .1uF 0805 capacitors. NEVER ONCE had a bad one. I still hand-solder a fair number of low production boards and prototypes, and have never seen a problem with MLCCs.   Jon

DaveC <not@home.cow>: Mar 27 06:19PM -0700 > 1I have a customer who does SMT repair work and I recently had him help me. I > watched him replace an 8 pin SOT for me. He had a dual lens machine like > something you might see on CSI.     Can you ask him what the make and model of his CSI machine is?

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 27 04:40PM -0400 > Had some boards at work with 'lytic caps leaking acid. SWMBO said no way bringing them home. Company bought a dishwasher explicitly for electronics cleaning and it works very well. I use a small amount of detergent, no active drying in the dishwasher but we also have a commercial food dehydrator for 'baking' tapes. 17 hours at 125F makes the boards look and work like new again.     We used a citrus based solvent in an industrial circuit board washer at the Microdyne plant in Ocala, Florida. I don't remember the brand, but it was a modified restaurant type dishwasher that sat on top of a stainless steel tank that held the solvent. The modifications were that tank, and an additional pump to circulate the solvent between the rinse stages. That cut the cleaning costs, and also trapped any parts that came off of new boards due to problems in the reflow oven. It had over a dozen solid state relays added, for the modified wash cycle.     Most of those early Delco solid state radios were a breeze to fix. Most spent less than 10 minutes on the bench, since the biggest failures in the '70s & '80s were open RF/IF transistors, or a shorted output transistor. They failed so often that the radio bench had its own inventory of parts right above the test equipment. It often took longer to do the paperwork than the actual repairs. :)   A curved hemostat, and clipping the leads to different lengths let you replace the RF transistors without removing the circuit board from the tuner. That trick alone, cut about 15 minutes from each repair. The first shop would remove the board, and quite often they would break the tabs off the coils and then they would wait for a new tuner to be ordered.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 27 04:41PM -0400 > I have alot of music on reel to reel. some of the oxide comes off of some of these. I know that their days are numbered. Can I save them? thanks Lenny   > What' the deal on baking tapess     That depends on the backing used. Acetate requires a different method than mylar.

DaveC <not@home.cow>: Mar 27 03:04PM -0700 > I have alot of music on reel to reel. some of the oxide comes off of some of > these. I know that their days are numbered. Can I save them? thanks Lenny   > What' the deal on baking tapess     Not nice to hijack a thread.   You're likely to get a greater response if you don't Reply to an existing message. Create a New message and add your own Subject.

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 27 10:11PM +0100 "Andy Burns" <feb2017-usenet@adslpipe.co.uk> wrote in message news:dloc6qFt296U1@mid.individual.net...   >> the model number has pretty much rubbed away. >> Anyone know of a gallery of such pictures?   > http://www.lg.com/uk/discontinued-microwave-ovens   Thanks - there was one looked almost similar, but the model number couldn't match what little I could make out from the label on the back.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 27 04:46PM -0400 Paul Drahn wrote:   > Interesting, but missing most amateur radio magazines.     www.archive.org has plenty of them. I have Byte, 73, and several other radio and computer collections that I downloaded from there, in PDF format.   They are also in the process of scanning and posting 10,000+ test equipment operating and service manuals from the now closed Manuals Plus warehouse.

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kenwyatt92@gmail.com: Mar 27 09:07AM -0700 Thanks works

legg <legg@nospam.magma.ca>: Mar 27 12:00PM -0500 This issue with 'cheap' vs neutrik:   You should all be aware, by now, that these connectors are all made in China - that difference in price is solely a distribution and sales issue - that quality is either demonstrated or not by the product itself - associated by trade brand name.   Therefor; there's no point in complaining about the quality of a part without identifying its brand name or mfr. Without this info, the warning is meaningless, because price is no longer a valid identifier.   As an example, recent Neutrik connector types, not commonly stocked domestically, were ordered at >$25 a pop and delivered from Shuersi Inc in Nanjing. Not cheap, good quality, reputable brand name from China.   Expecting these things to be manufactured by gnomes in Luxembourg is pure fantasy.   RL     On Wed, 16 Mar 2016 18:34:37 -0000, "Gareth Magennis"

Adrian Caspersz <email@here.invalid>: Mar 26 06:19PM On 25/03/16 15:17, Ralph Mowery wrote: > problem. Repaired it, and a week later he was back again, but said it would > be the last time for me to repair it. I said "oh". And he said he bought > another radio so he could leave them and not have to swap back and forth.   A friend blew up the RF power amp on an Icom 2m Transceiver by reverse connecting his car DC supply to the rig. A rig borrowed from the club shack. Much tears ;-(   It did have the diode that you describe reverse connected across the supply. Unfortunately that diode either didn't conduct fast enough, or decided it wasn't going to be part of the game and went open circuit before the fuse (and the amp... ) ...     -- Adrian C

jurb6006@gmail.com: Mar 26 11:26AM -0700 >"f you have an questions, please consult a real attorney. "   HA. Half of them are incompetent and the other half, well...   Used to work for one of those rental joints. Handled the repairs for the area, approximately the county. They reanted BFC SFS Fisher stereo systems using the CA-270 (discrete) amplifier. I worked on many of them. Underbuilt, and on purpose.   Looking at the PC board it was easy to see that it was designed to have commutators. The thing was considerably over 100 WPC and only had one pair of outputs per channel. You can get away with that with a commutating power supply. Also by the relay you could see the traces for what was obviously an offset detector.   All these parts were gone. By the relay all that was left was the time delay and the commutators were simply jumped out and all related components were omitted.   We replaced so many woofers because of that it ain't funny. Eventually the service manager got a source for some practically bulletproof woofers, I mean woofers that would stand up to 60 volts DC until the fuse blows. At least that was solved. Kinda.   Thing is, transistors and diodes are cheap. If I were on that side of that desk I would have them in there. However, in the US at least, the quarterly report is king.   Like this joke... A new CEO of a company gets three envelopes from the old CEO, tells him open them when things get tough. Sales drop later and he opens the first envelope and there is a note saying "Blame your predecessor". He does and all is fine, but later then sales and profits drop again, he opens the seconfd envelope and the note says "Reorganize". Well that works but then things go badly again later so he opens the third envelope and the note inside says "Get three envelopes and..."   As long as we publicly trade debt on these companies, they are bound to suck up the most money every day possible, It is fucking up the world, and the environment. In fact, if we cared enough to do something about it we would take the "green" attitude and let the democrats have at it. Laws that say you have to have parts for TVs n shit for like five years or so, instead of having them no longer available even during the warranty period. (this has happened) But even with that, can the government control the prices ? This is where they fucked up on the ACA, the price controls are not firm. Right now health insurance companies want doctors and hospitals to fuck them out of as much money as possible so they can make 20 % on it. Shit, oil companies would suck a mile of donkey dick to make 20 %.   The informed and non-addicted consumer is the best weapon here. Like "My TV was only two years old and it couldn't be fixed, I went to buy one with a long warranty but they had none, so now I DO NOT HAVE A TV". Start that shit and you won't need a grass roots lobby organization, the TV networks, cable companies and even Hollywood would do the lobbying for you.   But there is no solidarity among the sheeple. No chance to put up a serious boycott of anything. Anything. This is the age of instant gratification. Pitiful fucking species they are.

"pfjw@aol.com" <pfjw@aol.com>: Mar 26 01:00PM -0700 > >"f you have an questions, please consult a real attorney. "   > HA. Half of them are incompetent and the other half, well...   Shakespeare had it dead-right in his play Henry VI. Killing the lawyers was the sure route to tyranny, not the means to restore sanity to society.   Keep in mind that it is "society" that gives or has given us every evil from the Crusades to Jihad and ISIS, from Empress Wu to Donald Trump. Society is essentially insane, and functions only through pitiless and unrelenting control. Where such control has been destroyed, all remnants of societal function have failed. Modern examples include former strong-man states (Libya, Afghanistan, Iraq) where leadership was removed, not deposed. States where leadership was deposed (Iran, Soviet Russia, Balkans amongst others) function today after a fashion, and after an often horrendous shaking out - but they function none-the-less.   Circling back to electronics - we get exactly what we deserve, neither more nor less. It is entirely possible to purchase well-made electronics that are maintainable and have a truly indefinite service life - with that maintenance. Including all consumer entertainment electronics in this household, the newest daily-driver type item is a 6-year old blue-ray player to match the 8 year old plasma TV. The oldest is a 1962 tube stereo amplifier. If hobby (and functional) electronics are included, that would be a 1919 5-tube home-brew TRF radio driving a Magnavox horn.   If that first pair of $3.29 pair of Chinese underwear stayed on the shelf for the $3.69 pair of home-country underwear, we would not have this issue. But we are all-to-fast ready to give up our neighbor's jobs to 'save' that $0.40. Not quite understanding that without our neighbor's jobs our own are not long for this world.   Sorry for the insertion of politics here - but feeling sorry for ourselves is the last collective and several refuges for cowards. And "Let George Do It" is how we got here in the first place. The Chinese have not "taken" one single job from any one any where at any time. They were handed each and every one of those jobs complete and together with the plea "PLEASE take this burden from us!"   And. Lest ye "first world" people think for one hummingbird heartbeat that control over *you* is not pitiless - consider how much *you* are regulated, and at every turn. Between taxes, leases, licenses of various sorts, permits, insurance, credit cards, cash-transaction limits, speed limits, stop lights, parking meters, passports, health insurance, deeds, titles and on and on and on...   Put another way, Anarchy Bitch.   Peter Wieck Melrose Park, PA

"Ralph Mowery" <rmowery28146@earthlink.net>: Mar 26 04:18PM -0400 "Adrian Caspersz" <email@here.invalid> wrote in message news:dlo26cFqgaqU1@mid.individual.net... . > supply. Unfortunately that diode either didn't conduct fast enough, or > decided it wasn't going to be part of the game and went open circuit > before the fuse (and the amp... ) ...   Usually the most expensive part blows open to protect the fuse.

jurb6006@gmail.com: Mar 26 02:17PM -0700 pf, politics is what started this shit.   I used a slightly different analogy.   When you walked into Kmart and saw TVs on the shelf, a Zenith for $279 and a Sanyo for $229 you pocketed that fifty bucks and went and had a good time on it. Well the good times are over because YOU told the industry that cost is King, that you want it cheaper. You did not care about build quality, or this country and its well being. You wanted that half a yard in your wallet.   Time marched on and the results are in. We are fucked.   I see you think like me to some extent. Have ANY ideas on how to fix this shit without removing 90 % of the population ? I can't figure anything out. Even massive killing wouldn't work. NOTHING will work.   Reminds me of a joke about an old Indian. (American) Guy asks him about what he thinks about White Man. He replies "We had it good, Women did most of the work, we hunted and fished every day, no taxes, no debt, no problems. Only White Man stupid enough to think he can improve on that".   Progress. Think about progressives. Now think about conservatives who wanted to keep things the same, for better or worse. In fact republicans freed the slaves. Things seem to have flip flopped.   Slavery is a barbaric thing and should not be allowed in any civilised society. It is illegal in most parts of the world, but not in Israel and a few other countries in that region and in Asia and Africa. And that saying about "we should have picked our own cotton" has come true eventually for most countries that had slaves. Now it seems we should have picked our own oil.   But there are no true conservatives. I think the last one was Barry Goldwater, and he warned against letting the religious folk get hold of the republican party, because governance is all about compromise and people who think they are speaking for god will not compromise.   While he was right, he did not realize that later (like now) that these people would not be religious at all, but feign it for church support. And that is important in some districts. Like against homosexuals until their son comes out of the closet. Or against abortion but sends their mistress for a D & C when she gets knocked up by their adultery. Fucking hypocrites to the core.   Nixon was more of a Man and more honest than any of them today. Think about it, if you are doing backdoor deals and being dishonest, do you want tape recordings of it ? some say he did that because he was paranoid but the fact is they were out to get him. I believe he benefitted from the Watergate breakin, but I still do not believe he ordered it. However, like the impeached Bill Clinton and the assassinated JFK, he spoke against Israel. Most people do not know that alot of this shit happened right after they said mean shit to Israel.   So, with no true conservatives we are stuck with the liberals or oil company executives. That is your choice. Who are you going to vote against this time ?

"pfjw@aol.com" <pfjw@aol.com>: Mar 26 06:39PM -0700 > pf, politics is what started this shit.   > I see you think like me to some extent. Have ANY ideas on how to fix this shit without removing 90 % of the population ? I can't figure anything out. Even massive killing wouldn't work. NOTHING will work.   I am not so sure we think much alike. My politics as-practiced are considerably left of center, although not quite socialist. Mostly based on personal responsibility, the social contract and the basic fact that the world owes me nothing.   At the same time, the Human Race if seen as the functional equivalent of mold on an orange is doing a very efficient job of killing itself off, and apparently sooner rather than later. No problem for me, likely not for the kids either. But the grandkids are going to have a brutal time of it. A few tens of thousands of years from now, we will of interest only to whatever passes for archaeology and paleontology at the time, if even that. So, why sweat the small stuff with that perspective?   As of this moment, and based on present absolutely provable facts and long-term trends, the Malaysian archipelago land mass will be reduced by 70% (or more) by 2050. The present population is just under 30,000,000. And there is not one damned thing that you, I, or anyone else, collectively and severally, can do about that. AND, that is one single example. Florida - what happens when 30% of that state can no longer support either farming or a human population? New Jersey (small loss)? The entire Gulf Coast? Not to mention California. Just keeping it "American" here - the rest of you are also quite done, just not fully aware of how done, quite yet.   That we are fucked is absolute. That it is of our own making, equally so. But as a species we have always been better and destruction than at creation. Always. This particular disaster is pandemic, having nothing to do with race, color, creed, nation, state, orientation or personal preferences. Like a flat tax, we are all equally affected whether we like it or not.   Peter Wieck Melrose Park, PA

jurb6006@gmail.com: Mar 26 07:54PM -0700 I think collectivism and individualism can coexist, but we have not figured the method.

Jon Elson <elson@pico-systems.com>: Mar 26 11:02PM -0500 Tim Schwartz wrote:     > I'll have side with the manufacturer here. It is not possible to make > any product 'idiot proof' as someone will come up with a bigger idiot. I make a line of PWM servo amplifiers, using a bunch of TO-220 FETs. A mechanical engineer bought some, and saw those little plastic things clamped under the transistors and decided they couldn't conduct heat well, so he took them out, put a glob of thermal grease under them and clamped them down tight. Hooked the whole system up and turned it on. There was a thunderclap and a huge flash, and everything he had bought from me was reduced to charred rubble. The little plastic things were good Bergquist thermal conductive pads, and work fine to allow the amp to run at 20 A continuously. I fixed one amp just to see how bad it was, well every semi in the thing was toast. It must have got +80 V into the +12 logic supply.   That's the biggest idiot I've had so far...   Jon

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Mar 27 03:12PM +1100 On 26/03/2016 10:22 PM, Mark Zacharias wrote: > microprocessor-based turn-on and protection circuits would have to be > bypassed.   > Mark Z.   **Apart from the Variac™, pretty much it. I must admit some trepidation the first few times I was required to perform this test.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

stratus46@yahoo.com: Mar 26 11:28PM -0700 On Friday, March 25, 2016 at 8:12:24 AM UTC-7, Ralph Mowery wrote: > problem. Repaired it, and a week later he was back again, but said it would > be the last time for me to repair it. I said "oh". And he said he bought > another radio so he could leave them and not have to swap back and forth.   Had one like yours with the fuse and protect diode blowing. Second time I had to repair it I checked what he was actually doing and found the reverse polarized battery. His car was an early '60 Ford van with a generator, NOT an alternator and when the battery was dead he jumped it backwards and converted it to positive ground.   G²

jurb6006@gmail.com: Mar 27 06:03AM -0700 >"His car was an early '60 Ford van with a generator, NOT an >alternator and when the battery was dead he jumped it backwards and >converted it to positive ground. "   Yup. And if the radio was all tubes it would run just fine. No way to tell without a meter.

T i m <news@spaced.me.uk>: Mar 26 09:38PM Hi all,   I was asked to look at an electric scooter for a friend today. His friend bought it directly from China, ran it ok for a couple of months and then it just stopped working (so no point trying to send it back from the UK).   Whilst I'm reasonably comfortable with basic electrics and electronics I'm not familiar with the sort of things you find now days around Lixx type cells and packs and hence why I am looking for some advice here please.   FWIW, we connected the 36V, 40 cell pack (possibly 4 x 10 or 10 x 4 in parallel?) up to the scooter charger and saw the terminal voltage go from around 36 to 40V (charger max 42V) and the current initially sit at 2A and then start dropping to about 1.8A after maybe an hour. I believe the cells are these:   http://www.ax-ps.com/pdf/datenblatt/LR1865_SI.pdf   (making the pack ~36V x 8.8 Ah)   Putting a load (3 x 12V x 21W lamps in series) across the battery output showed nothing. Putting the load across the cell monitoring wires (eg, directly on the battery) had the lamps shining brightly (indicating there was nothing wrong with the battery itself, at least with a load of around 2A)?   We then turned to the BCM, un wrapped it and found and tested a (65 degree) thermal switch and that seemed ok (short cct).   I've since split the BCM and this is the working side (the other half is the monitoring board [1] and connects the main board via a 4 pin link shown at the top):   https://dl.dropboxusercontent.com/u/5772409/BCM%201.jpg   The two wires you just see top right go to the 5A thermal switch, the blue wire top left is the negative out ... and the pad J2, top right is as marked, connected directly to the battery -ve. So this board and all the cell monitoring connections work WRT the battery Ov?   The charging connector is basically across the output.   Now, from Googling about I think I understand some of the components on that board may control the charging and that seems to work (or at least not be dead), so I think we are looking at something that may enable the output, presumably as long as the battery voltage is sufficiently high and the pack temperature is less than 65 DegC etc?   The T0-220 devices seem to be 3 x RU75ND8R mosfets + 1 x HY1807.   https://dl.dropboxusercontent.com/u/5772409/RU75N08R%20datasheet.pdf   https://dl.dropboxusercontent.com/u/5772409/HY1807%20datasheet.pdf   From what I can see the gates of the two devices to the left are driven from the two EL817 photocouplers seen bottom left.   https://dl.dropboxusercontent.com/u/5772409/EL817%20datasheet.pdf   I found something that might give some hint of a similar issue here: https://endless-sphere.com/forums/viewtopic.php?f=14&t=67012   And a more detailed description of how it might work on the last post: https://endless-sphere.com/forums/viewtopic.php?f=14&t=67012#p1008437   So, I'm not sure where to go next. I do have one of those little component testers so, assuming I couldn't test the power devices in circuit I could de-solder them (FETs) and may be able to test them but what are the chances of that being the fault and it not be some of the other (SM) circuitry please?     Cheers, T i m   [1] https://dl.dropboxusercontent.com/u/5772409/BCM%202.jpg https://dl.dropboxusercontent.com/u/5772409/BCM%203.jpg

M Philbrook <jamie_ka1lpa@charter.net>: Mar 26 07:06PM -0500 In article <dpsdfbh1mm2c9nvh0pt3bf8svun37rruhs@4ax.com>, news@spaced.me.uk says...   > Cheers, T i m   > [1] https://dl.dropboxusercontent.com/u/5772409/BCM%202.jpg > https://dl.dropboxusercontent.com/u/5772409/BCM%203.jpg   That driver board has a lot of bad solder joints on it...   Use loup if you have one put some clean solder on the joints where the power fets are especially.   Jamie

c4urs11 <c4urs11@domain.hidden>: Mar 27 12:53AM On Sat, 26 Mar 2016 21:38:52 +0000, T i m wrote:   > and then it just stopped working   Where is R0?

T i m <news@spaced.me.uk>: Mar 27 02:06AM +0100 >On Sat, 26 Mar 2016 21:38:52 +0000, T i m wrote:   >> and then it just stopped working   >Where is R0?   Good question. ;-)   The only thing I can offer is I don't think it's fallen off and if it was in parallel with the thermal trip, would only come into play if/when that tripped (went o/c)? <shrug>   Cheers, T i m

T i m <news@spaced.me.uk>: Mar 27 02:13AM +0100 On Sat, 26 Mar 2016 19:06:00 -0500, M Philbrook <jamie_ka1lpa@charter.net> wrote:   <snip>       > That driver board has a lot of bad solder joints on it...   This one?   https://dl.dropboxusercontent.com/u/5772409/BCM%201.jpg     >Use loup if you have one put some clean solder on the joints where > the power fets are especially.   Whilst I agree they don't look very pretty I do have a loup and have just given it a look over and *I* can't see anything obvious ... but then I many not be able to spot something that is obvious to others. ;-)   If I'm there re-doing the joints I might as well take the FETs off one at a time and put them in my tester and see what it says? Or at least do the two that don't seem to be involved in the charging (that I believe works etc).   Cheers, T i m

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 26 08:24PM Someone's been over eager with the cleaning cloth - the model number has pretty much rubbed away.   It looks like maybe CO800??AW.   I've Googled for pictures hoping for an identification, but didn't have much luck with that.   Anyone know of a gallery of such pictures?   Thanks.

c4urs11 <c4urs11@domain.hidden>: Mar 26 09:09PM On Sat, 26 Mar 2016 20:24:08 +0000, Ian Field wrote: > much luck with that.   > Anyone know of a gallery of such pictures?   > Thanks.   I find it a lot easier to google spare part vendors. Every part belongs to a number, so they usually have extensive lists. I tried this on <http://www.espares.co.uk/browse/at1095ma81/microwaves/lg> and it promises a list of over 900 models.   Cheers

Andy Burns <feb2017-usenet@adslpipe.co.uk>: Mar 26 09:10PM Ian Field wrote:   > the model number has pretty much rubbed away. > Anyone know of a gallery of such pictures?   http://www.lg.com/uk/discontinued-microwave-ovens

Andre Majorel <cheney@halliburton.com>: Mar 26 07:56PM > If it uses an MLCC capacitor, use a hot air gun to reflow, not > a soldering iron tip.   News to me. In what way are multi-layer ceramic caps and soldering irons incompatible ?   -- André Majorel http://www.teaser.fr/~amajorel/ J'ai des vrais problèmes, vous avez des faux problèmes.

M Philbrook <jamie_ka1lpa@charter.net>: Mar 26 02:31PM -0500 In article <a0996009-e50c-4562-adb7-c501bf766d16@googlegroups.com>, jurb6006@gmail.com says...   > So is this indicating I got a leaky magnetron ? If I can get a cap foro ten bucks I will fix it, but magnetrons are more expensive and this thing is well, it is a nice, decent performing uWave oven. > Not the best but I have seen alot worse. The heat is even and the control system is not hard to deal with. It is a Magic Chef, input power is stated as 1,500 watts, so it is what, 1,300 ? Nice, small height wise but a bit wider than the really small ones.   > I just think when you got something good you should try to keep it going. There is no money involved in this one.   clamp on probes or meters are wonderful devices and much safer working hot. check heater current and HV current.   Jamie

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"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 26 06:22AM -0500 "Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message news:dlmorsFg49tU2@mid.individual.net...   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   If I recall correctly that procedure used a variac and the test stopped an a certain current (I think it was 4 amps) through the amp meter which was the only "load". A modern amp would pass that test as well, but the microprocessor-based turn-on and protection circuits would have to be bypassed.   Mark Z.

"Mark Zacharias" <mark_zacharias@sbcglobal.net>: Mar 26 06:11AM -0500 "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:m4sbfbtj3k3b1hcjnca9t86o566tel84o4@4ax.com... > 150 Felker St #D http://www.LearnByDestroying.com > Santa Cruz CA 95060 http://802.11junk.com > Skype: JeffLiebermann AE6KS 831-336-2558   You, sir - are an evil Genius!   mz

Tim Schwartz <tim@bristolnj.com>: Mar 26 08:52AM -0400 On 3/25/2016 11:52 PM, John Heath wrote: >> Santa Cruz CA 95060 http://802.11junk.com >> Skype: JeffLiebermann AE6KS 831-336-2558   > I have heard this argument too many times as if the costumer is responsible for electrical engineering issues. The customer paid for the amplifier leading a profit for the manufacturer. It is the manufacturer that is responsible to made sure the amplifier is idiot proof. Amplifiers have current limiting circuits which means you can sort the outputs all day long without any damage. If the manufacturer can not be bothered to be responsible for their own engineering leading to output transistor failure than they are in the wrong business. There is no such thing as a costumer that is wrong as he is the one that is paying the money. The failure is always up stream from the costumer. I will now get of my soap box.   I'll have side with the manufacturer here. It is not possible to make any product 'idiot proof' as someone will come up with a bigger idiot.   By these this standard, car manufacturers should build a car that won't sustain any damage because the driver is reading the newspaper, texting or talking on a phone rather than driving. Or from a mechanical side, not add oil when the light comes on. Not possible, at least not yet. The end user must also take reasonable care.   Shorting speaker leads is NOT something that the manufacturer can make idiot proof without significantly increasing cost and/or compromising performance.   Regards, Tim

"pfjw@aol.com" <pfjw@aol.com>: Mar 26 06:08AM -0700 On Friday, March 25, 2016 at 11:53:02 PM UTC-4, John Heath wrote:   > I have heard this argument too many times as if the costumer is responsible for electrical engineering issues. The customer paid for the amplifier leading a profit for the manufacturer. It is the manufacturer that is responsible to made sure the amplifier is idiot proof. Amplifiers have current limiting circuits which means you can sort the outputs all day long without any damage. If the manufacturer can not be bothered to be responsible for their own engineering leading to output transistor failure than they are in the wrong business. There is no such thing as a costumer that is wrong as he is the one that is paying the money. The failure is always up stream from the costumer. I will now get of my soap box.   There is what I define as the Great Aunt Esmeralda issue:   Great Aunt Esmeralda is typically in her late 80s, but not frail. She has each and every one of her marbles, and is in full control of same. She is set in her ways, but neither stupid nor fearful. She resists change, but only because at her stage in life she has things right where she wants them. She also votes, every time for every election at every level and is known to do so.   As a concept, she is directly responsible for the delay of the shut-off of Analog TV in the US, until its advocates could develop a more intuitive interface. If Esmeralda had to diddle around to turn on her soaps, and missed the first five minutes of the show because the interface was not fully intuitive, she would make dammed sure her congressman knew it! Starting with her Alderman.   At the same time, Great Aunt Esmeralda understands that as a consumer, she has some responsibility to 'read the directions' as it were. And as a consumer/customer, to seek clarification when in doubt - and make damned sure that the provider of her goods and services writes directions that are able to be followed by any reasonable consumer with normal intelligence - NO MORE!   I have legacy amplifiers from AR, Dynaco, Revox and HK-Citation. EVERY ONE OF THEM cautions against shorting the outputs. Two manufacturers (AR & Dynaco) cautions against running their amplifiers with input, but no connected load. Each, in its own way, also cautions against shorting the two channels together. Several of them add protection circuits (Revox & Dynaco), some add fuses, internal or external (AR & HK) and so forth. And in every case, the directions are clear and unambiguous. Great Aunt Esmeralda would have no difficulty with them, and if she screwed up the connections resulting in a melt-down, she would be fully OK with accepting the consequences.   What you suggest is similar to making an automobile manufacturer liable for the consequences of the fact that the accelerator and brakes may be applied at the same time.... Driver error (pilot error/user error) is a real phenomenon such that reasonable accommodations must be made, but the danger of same cannot be obviated.   Against stupidity the very gods Themselves contend in vain.   Schiller.

Jeff Liebermann <jeffl@cruzio.com>: Mar 26 09:27AM -0700 On Sat, 26 Mar 2016 06:11:45 -0500, "Mark Zacharias" >> doesn't stink very much, but white mineral oil really reeks.   >You, sir - are an evil Genius! >mz   Thank you. Think of it as a VERY slow blow fuse with a built in "indicator". I suspect that even the most dense customer will recognize smoke as an indication that perhaps something is very wrong.   Many years ago, when I was an aspiring juvenile delinquent, I removed one end of a 3AG cartridge fuse, stuffed it with cotton, added a few drops of 3-in-1 oil, installed a 0.5 ohm resistor, and somehow soldered it back together without starting a fire. I'll pretend not to remember how I did that. The plan was to make some sort of bomb to irritate some of my friends. Instead of exploding, it produced a substantial amount of smoke and attracted some unwanted official attention. While I don't believe that the world needs a smoking fuse, a similar leaded component might sell to like minded dangerous individuals, such as myself, as an over current alerting system. With some additional complexity, I could add a chemical timer set to slightly longer than the warranty period. I have some ideas on how to do an SMT version.   Hmmm.... Kickstarter perhaps?   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Mar 26 09:47AM -0700 On Fri, 25 Mar 2016 20:52:58 -0700 (PDT), John Heath >There is no such thing as a costumer that is wrong as he is >the one that is paying the money. The failure is always up >stream from the costumer. I will now get of my soap box.   In the past, when I needed some entertainment, I would read product liability horror stories. It eventually became somewhat of a hobby until I was overwhelmed with horror stories.   Your position is quite among customers and product liability attorneys. The legal responsibility is a moving target, varying depending on court decisions, commercial law, and both state and federal laws. Over the years, it has swung in both directions, but at no time has it ever been absolute. The manufacturer, retailer, and customer all have their areas of responsibility with considerable overlap.   Very briefly, the courts have recognized that manufacturers cannot produce a 100% safe and reliable product. If they did, nobody could afford it anyway. One compromise is that if a manufacturer can show due diligence in informing the end user that there are some hazards involved in using the product, and the customer is assumed to have been so informed, then the customer cannot claim that they destroyed the product or injured themselves in the manner specified in the documentation. This is where the ever growing mass of legal documents and "read me first" papers originate. If the manual warns that shorting the speaker output is a bad idea, the court will not award the customer damages if they ignore the warning and short the speaker leads.   The other side of this coin is whether a "reasonable person" expects products to operate in some manner. In this case, if literally every other audio amp manufacturer includes speaker short circuit protection in their products, but this one does not, a reasonable person would probably expect that every amp is short circuit proof. Depending on the court, that could be considered sufficient for the customer to claim that they did not receive a product "suitable for the intended purpose".   With today's low cost of electronic manufacturing, it is often cheaper for a manufacturer to replace the few amps that a few clueless customers manage to blow up, than to include protection circuitry in every product. For example, if adding the protection circuitry required an additional $5 in parts and Yamaha made 250,000 of these amps, then that's $1.25 million in "excess" cost. However, replacing perhaps 1,000 amplifiers, at a cost to sales of about $50/ea or $50,000 is much cheaper. This is probably why Yamaha honored the warranty.   If you have an questions, please consult a real attorney.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Cursitor Doom <curd@notformail.com>: Mar 26 03:02PM On Sat, 26 Mar 2016 10:43:40 -0400, bitrex wrote:     > Is there any way to easily detach this thing without desoldering it from > the board?   > http://tinyurl.com/j5cpgu2   Not sure what you mean, but have x-posted this to a more appropriate group.

dansabrservices@yahoo.com: Mar 26 08:40AM -0700 On Saturday, March 26, 2016 at 11:06:14 AM UTC-4, Cursitor Doom wrote:   > > http://tinyurl.com/j5cpgu2   > Not sure what you mean, but have x-posted this to a more appropriate > group.   Near as I can tell from the picture, this is an unsolder job only. This is a convenient way to solder a bunch of wires in a single coordinated way. Unsolder the connections and mark one side to be sure you get the orientation correct.   Dan

chrisdac@gmail.com: Mar 25 12:23PM -0700 Dear Mr. Horne,   A sincere THANK YOU for your post. Your details and explanation were spot on. I googled "sharp microwave R-1410A" and this was the first link.   I followed your instructions to a T except for the order pizza part. I felt as though thanking you first was more important.   -Chris in Massachusetts

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