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Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 15 12:11PM -0500 On 12/15/2015 11:49 AM, Jeff Liebermann wrote: > I have two of them that run without problems. I also have about 5 > customers that have them. Batteries have been lasting about 5 years > and no lightning bolts or smog problems.   I have three UPS Back-UPS 750s, rebadged as IBM eServer UPS 750T. They're really cheap on eBay, and run great. I had one overheat about a year ago, so I threw it out, but the current three have been running flawlessly for years and don't eat batteries at all.   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

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Dec 15 01:07PM -0500 On 12/15/2015 12:11 PM, Phil Hobbs wrote: > They're really cheap on eBay, and run great. I had one overheat about a > year ago, so I threw it out, but the current three have been running > flawlessly for years and don't eat batteries at all.   Misspoke. They're rebadged SmartUPSes, not BackUPSes.   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

"dangerous dan" <dangerous@dan.com>: Dec 15 12:26PM -0600 > Not sure if I can easily get apart and reuse that mechanical setup. > Suggestions please. > --- news://freenews.netfront.net/ - complaints: news@netfront.net ---   If you have a Interstate Battery nearby, they keep lots of UPS batteries in stock.     -- Usenet Reader for Android http://android.newsgroupstats.hk

Jeff Liebermann <jeffl@cruzio.com>: Dec 15 03:39PM -0800 On Tue, 15 Dec 2015 13:07:15 -0500, Phil Hobbs   >Misspoke. They're rebadged SmartUPSes, not BackUPSes.   For those not familiar with APC marketspeak, the SmartUPS series are all sine wave generators, most with continuous backup (i.e. no power transfer relay). The BackUPS series are modified sine wave, also known as step wise stair case generators, usually with a relay to do the power transfer. The SmartUPS series does a better job tolerating the crappy waveforms produced by emergency generators than the BackUPS.   I just looked at my pile of dead and semi-dead APC UPS's. All have one thing in common... no batteries. If I sell one, I buy the batteries. Looking at the pile, there are 10 UPS's, only one of which is a SmartUPS. The SmartUPS's are all in service. The BackUPS's all sit on my shelf.   I get quite a few SmartUPS's from the local recycler. People recycle them when the batteries die because they don't want to replace expensive batteries. I buy the electronics and supply my own batteries. So far, they all have worked just fine.   -- 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

Clifford Heath <no.spam@please.net>: Dec 16 10:06AM +1100 On 16/12/15 03:09, Ralph Mowery wrote: > light bulb next to the computer to heat it up. The computer wold come on > and work fine unless he shut it off , then he had to heat it up again with > the light bulb.   We had a couple of old Fujitsu "Eagle" disk drives - 500MB or so - inherited when we started a company in 1990. These were about 25-30kg, and 500x350x700mm in size - so you needed two strong sets of hands to get them on and off the rack mountings (they were on slides).   Anyhow, as they got older, the spindle bearings became sticky, so they wouldn't spin up after a power fail that was long enough for them to cool down. We used to get them off the racks, with one bloke at each end, then power them up and give a sudden lateral rotation to break the stiction of the bearings. Quite a risky business, coordinating two blokes to do that suddenly enough without dropping the drive, but it worked a number of times before we made enough money to afford to replace them.   We started a software company with 25 initial employees (staff buy-out) and a grand total of 2.2GB of storage - in the entire company. Imagine that!   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: Dec 15 03:15PM -0800 On Tue, 15 Dec 2015 11:09:55 -0500, "Ralph Mowery"   >Going to look bad when it is a bad power cable or socket.   Nope. Both passed the wiggle test.   >light bulb next to the computer to heat it up. The computer wold come on >and work fine unless he shut it off , then he had to heat it up again with >the light bulb.   I'm getting that now on my home desktop computah. I don't bother to heat the house much at night. When I wake up, it's about 45F (7.2C) inside the house. When I turn on my desktop computah, the fan makes some odd noises but eventually quiets down. The hard disk seems to boot normally, but usually some programs add oddly or crash. I reboot and they then act normally. It's probably read errors on the hard disk, but SMART shows nothing interesting. At this time, I boot to the BIOS screen, wait about 10-15 mins, and then boot normally.   -- 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

Clifford Heath <no.spam@please.net>: Dec 16 10:28AM +1100 On 16/12/15 10:15, Jeff Liebermann wrote: > heat the house much at night. When I wake up, it's about 45F (7.2C) > inside the house. When I turn on my desktop computah, the fan makes > some odd noises but eventually quiets down   Take the fan out and refit it, rotated 90 degrees.   The bushings wear the holes elliptical, and the rotation changes the vibration modes.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 15 06:36PM -0500 "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:kf717bp4p5j377q45i5t8qvfq51q500cj7@4ax.com... > and they then act normally. It's probably read errors on the hard > disk, but SMART shows nothing interesting. At this time, I boot to > the BIOS screen, wait about 10-15 mins, and then boot normally.   If I got out of bed and it was 45 F, I would be looking into the heating system first. I don't function when it is that cold.   Sounds like you may want to look into a solid state drive for the computer so it will start up cold.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Dec 15 08:53AM -0800 On Tuesday, December 15, 2015 at 7:37:47 AM UTC-8, John Robertson wrote:   > Capacitors?   Back in the old days, McIntosh used to have clinics where owners could have their equipment restored up to specifications for free. I remember watching them start by routinely replacing all of the cathode bypass electrolytics; they would then check and replace the tubes, as neceeary. They rarely had to go farther (but would if required).

Jeff Liebermann <jeffl@cruzio.com>: Dec 15 09:17AM -0800 On Mon, 14 Dec 2015 14:05:17 -0000 (UTC), Cursitor Doom >troubleshooting? I'll kick off by suggesting:   >1. Assume nothing.   >Perhaps we can assemble a list of golden rules....   There is no correct approach. There are only approaches that work under specific circumstances. Like the universal solution to all problems, and the answer to all questions (42), the correct approach are only useful after you found the solution.   1. That which you know to be functional, beyond any need of checking, is usually the problem.   2. Solutions found after midnight are best forgotten as they are likely to be the product of temporary insanity.   3. Things go better if you have a schematic, gallon of coffee, a working unit to compare, and a parts unit to cannibalize.   4. While it is theoretically possible to work on two problems at one time, it is much easier to fix problems in the order they appear. I like to fix the little things first.   5. Nothing is considered fixed until after it is cleaned. If you can't fix it, at least make it look like it's been fixed.   6. Approximately half the disassembly videos on YouTube are wrong, useless, dangerous, or out of focus.   7. For a good collection of counterfeit parts, just buy them on eBay.   8. Your most valuable tool is a visual inspection, often with a magnifying glass. This helps identify exploded, incinerated, or overheated components. It also shows where the previous repairs were performed, a sure sign of problems to come.   9. Always ignore the symptoms and theories of the customer. They're often misleading and will usually waste your time chasing down false theories. Test the unit yourself to confirm the symptoms. I often find a very different set of problems or that the buzzwords in the original description were misused.   10. Fix everything that you find, even if the customer hasn't complained about it. If it's wrong, even slightly, they'll be back to complain and you might end up fixing it for free.   11. Take photographs of before and after. Treat is as if it were evidence in a lawsuit or insurance investigation. I also take a photo of the insides of the customers laptop, and use it for wallpaper on their desktop. The reactions are "interesting" and help fortify my exorbitant rates. The photos also help when I can't recall how to put it back together.   12. Never do what cannot be undone. For computahs, make an image backup of the hard disk both before and after the repair. Image backup programs are now very fast and Terabyte USB 3.0 hard disk drives are cheap.   13. No repair is complete without a culprit. The first step to doing a repair is to blame someone or something. This is an important part of the repair as most customers are worried that they may have done something wrong (such as buying a piece of junk). By blaming someone else, this eases their guilty conscience.   14. Never let the customer see you reading the instruction manual. They will immediately suspect that you don't know what you're doing.   15. Beware of spare parts left over after reassembly.   More later. I'm late (as usual).   -- 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>: Dec 15 06:16PM On Tue, 15 Dec 2015 07:37:42 -0800, John Robertson wrote:   > than about 30 years old in our vintage game monitors and amplifiers > (video/pinball/jukebox) as this saves a tremendous amount of > troubleshooting time.   Does it, though? I mean, you could save even more time by just running all the caps through an ESR meter test and just replacing those that fail. Given how fragile some of those old PCB traces can be, I'd only want to replace the caps that really way out of spec.

John Robertson <spam@flippers.com>: Dec 15 10:33AM -0800 On 12/15/2015 10:16 AM, Cursitor Doom wrote: > all the caps through an ESR meter test and just replacing those that > fail. Given how fragile some of those old PCB traces can be, I'd only > want to replace the caps that really way out of spec.   Um, we use temperature controlled soldering irons and the traces on most of our arcade grade games stand several soldering cycles...   The Bob Parker design ESR meter (which we've been selling since 1999) doesn't handle small value caps (under 10UFD) very well, and on the monitors a bunch are 4.7ufd or less.   There are only about fifteen caps in the average monitor, and it takes about an hour to pull the chassis, replace the caps, do the ring/LOPT test, check the fuse, reinstall and start the burn-in process. Then it goes away for five to ten years.   Amps can be worse, particularly early stereo tube amps where all the parts are connected on standoffs - those can take three to five hours to recap. They don't come back for ten to twenty years after a recap and resistor check (tubes too of course).   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."

John-Del <ohger1s@aol.com>: Dec 15 10:50AM -0800 On Tuesday, December 15, 2015 at 1:18:52 PM UTC-5, Cursitor Doom wrote: > all the caps through an ESR meter test and just replacing those that > fail. Given how fragile some of those old PCB traces can be, I'd only > want to replace the caps that really way out of spec.   I used to do a local vendor's arcade monitors, and I can tell you that a cap that might pass an ESR test may destroy the vertical output on power up when left to sit in an unheated warehouse a week or so during it's route rotation.   I always recapped arcade monitors because of the wild temp extremes they would often see.

Jon Elson <jmelson@wustl.edu>: Dec 15 03:49PM -0600 Jeff Liebermann wrote:     > 3. Things go better if you have a schematic, gallon of coffee, a > working unit to compare, and a parts unit to cannibalize.   Oh wow! This one is up there with Murphy's law!   And, unless you are the manufacturer of said device, much of the above will never be available.   Jon

Cydrome Leader <presence@MUNGEpanix.com>: Dec 15 11:08PM > later." I cannot tell you how many problems I solved while doing that. > Sometimes getting just getting away from the problem allows clearer > thought.   I've stared at well written service manuals (these actually exist, but tend to be old) that just made no sense until the next day, or after a break. Not a fan of touching service manuals with diry hands either.

Cydrome Leader <presence@MUNGEpanix.com>: Dec 15 11:13PM > Most important, assume nothing. As soon as you think you know what is wrong, it is impossible not to ignore contrary evidence.   > I work with some engineers who are good designers because they keep their brain fixed on the goal and work through every obstacle. They THINK they are also good troubleshooters but they are wrong, obstinately frustratingly wrong, for the same reason. They KNOW what is wrong too early, and nothing shakes their belief.   > Second. When anybody tells you the symptoms, listen. When they tell you why, STOP! Don't listen. It will probably be theoretically impossible, and then you end up doubting the symptoms. Sorry but this is especially a problem with techs and mechanics. They observe correctly but theorize contrary to the laws of physics, so you need to stop listening when they get to that point.   I helps to try to figure out what a device should do when it is working. Extracting this information is sometimes really hard when people are fixating on what's broken and keep talking in circles.

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 15 06:27PM -0500 "Cydrome Leader" <presence@MUNGEpanix.com> wrote in message news:n4q6qt$2tt$2@reader1.panix.com... >> I helps to try to figure out what a device should do when it is working. > Extracting this information is sometimes really hard when people are > fixating on what's broken and keep talking in circles.   I got a call at the plant I worked at from an equipment operator. When I got there he said an indicator light would not come on. He had changed bulbs and even swappend a glowing one with the one that would not come on to show me it was not the bulb.   I asked him about the equipment as I did not know anything about it. He said he presses one button and a light comes on , then he presses the second button and another light comes on, but now the second light would not come on. As this was just in a control room and the equipment could be located anywhere in the plant I asked him several times about the equipment and all I could get out of him was he just pressse the buttons and the lights should come. He did not seem to know where the equipment was, just the indicator lights..

Jeff Liebermann <jeffl@cruzio.com>: Dec 15 03:28PM -0800 On Tue, 15 Dec 2015 15:49:13 -0600, Jon Elson <jmelson@wustl.edu> wrote:     >Oh wow! This one is up there with Murphy's law!   >And, unless you are the manufacturer of said device, much of the above will >never be available.   Gallons of coffee are available at your local supermarket.   I practice what I preach. If really want something to work, I buy 3 of them, and cannibalize one or two for parts to make one of them work. I also buy or download the manuals: <http://802.11junk.com/jeffl/pics/home/slides/BL-shop5.html> Notice that there are three HP8620C sweep generators, and three SSI/Wavetek 3000b service monitors in the photo.   If the schematics once existed, they will eventually appear on someones web pile. The sellers of manuals seem to be very good at obtaining obscure manuals. I've posed schematics for some of the stuff I've helped design on my web pile. Much more difficult are schematics with voltages and waveforms. That used to be standard practice until about the 1970's, but has lost favor probably because it requires the schematics to be printed in color.   -- 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

"Ralph Mowery" <rmowery28146@earthlink.net>: Dec 15 06:31PM -0500 "Cydrome Leader" <presence@MUNGEpanix.com> wrote in message news:n4q6hr$2tt$1@reader1.panix.com...   > I've stared at well written service manuals (these actually exist, but > tend to be old) that just made no sense until the next day, or after a > break. Not a fan of touching service manuals with diry hands either.   Where I worked we had a copy machine in the shop and I would usually copy the important pages of the service manual to take with me. Usually had them already copied in a book I kept so I could fine the important pages quick and took a copy of that with me.   The electrical blue prints for much of the wiring and some equipment was on a computer and we had a large plotter so could run off what we needed to take with us. Sometimes I would make notes on the copies and leave them in the electrical cabinet, or just write inside the cabinet with a marking pen.

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Dec 15 07:08PM > adjust treble and bass to try to get something like > 3dB down at 300Hz , flat between 600Hz and 3KHz, +3dB broad hump between > 3 KHz and 7KHz and as little as possible above 8KHz.   For archive work, don't throw away anything you don't have to. Keep it wide open and flat (or "Blumleined") from 20c/s to 20Kc/s unless somethng is overloading. The 300c/s characteristic is easily achieved with a single RC time constant in a feedback loop (the time constant is 531 microseconds) giving bass bost. This should be sensibly limited by another pole that comes in around 20c/s, because you do not want to be calling for infinity gain at D.C.   A straightforward variable circuit that can be connected directly to the pickup is shown at: http://www.poppyrecords.co.uk/other/Equaliser/Equaliser.gif   The time constant can be read directly off the dial of the multi-turn pot.     If you want something more elaborate, try: http://www.poppyrecords.co.uk/other/Equaliser/MultipleEq.htm   When you have made your 'Archive' copy, you can play that and then limit the bandwidth or do whatever is necessary to produce a 'Playback' copy that sounds easier on the ear.   > Try a couple of seconds recording at centre, mid and outer, to check for > enough but minimum stylus weight and antiskating , then review those > recordings before going for a full run on 3 recording media.   It is a pity you are using a radial arm, but you can usually get away with it if you use a conical stylus (rather than truncated elliptical, which will emphasise the playback 'azimuth error' between the two points of contact on the groove walls). Do you have a stylus in the correct range for coarse-groove recordings? A microgroove stylus will give useless results (unless you happen to be incredibly lucky)   > I've not set modified the deck yet, I'll time the revs when done, but > it should be 50.3 RPM assuming 50Hz mains   Why not use the 45 rpm speed and run it from a 56c/s supply? That will save a lot of hassle - any well-designed amplifier rated at about 100 watts, fed through a suitable reversed mains transformer, will do the job.     If you live anywhere within travelling distance of Bath, you could bring the disc here and I'll see what I can do with it.     (By the way, I'm beginning to have my doubts as to whether the blank was a genuine Marguerite product or whether it was made by some other company.)   -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

thekmanrocks@gmail.com: Dec 15 11:35AM -0800 Adrian Tuddenham wrote: "(If the surface is mud-cracked or there is red powder on it, the disc will be in a dangerous condition and you need to seek specialist help to avoid starting a disastrous fire.)"   😱 ??   Setting a record on fire just by playing it?

dplatt@coop.radagast.org (Dave Platt): Dec 15 12:46PM -0800 >specialist help to avoid starting a disastrous fire.)"   >😱 ??   >Setting a record on fire just by playing it?   If the disc is old enough that the cutting surface was celluloid, or cellulose nitrate (rather than the cellulose acetate used in later years) then it might be bad juju!   Celluloid deteriorates with age - the camphor escapes and you're left with just cellulose nitrate, which becomes increasingly brittle.   Cellulose nitrate is known by another name - "guncotton". Also "flash paper". It's a primary ingredient in smokeless gunpowder.   If something made of celluloid or cellulose nitrate has deteriorated to the point where it's forming a powder... well, that powder might be touchy enough that even a static-electric spark might ignite it, and FOOM.   I'd also be concerned about diamond-stylus-to-groove friction - there's a *lot* of pressure on that tiny contact surface. I've heard that the heat generated during playback of an LP is actually sufficient to melt a very thin surface layer of the vinyl!   On the other hand, if it's a true "acetate" disc (made with cellulose acetate rather than cellulose nitrate) the flammability problem would be much less. If this material is deteriorating there might be a distinct odor of vinegar, as the acetic acid dissociates from the cellulose.   As to playing the disc... the cat's meow might be to gain access to an ELP laser turntable, which doesn't use a physical-contact stylus at all. No wear... but not cheap nor common.

adrian@poppyrecords.invalid.invalid (Adrian Tuddenham): Dec 15 11:13PM > >seek specialist help to avoid starting a disastrous fire.)"   > >😱 ??   > >Setting a record on fire just by playing it?   Yes, unlikely but possible.     [...] > On the other hand, if it's a true "acetate" disc (made with cellulose > acetate rather than cellulose nitrate)...   It won't be. Cellulose Acetate can only be embossed, not cut. It was not used for direct-cut discs. (The manufacturers sometimes called their nitrate discs "Acetates", but this was deliberately misleading because of the bad reputation that nitrate had gained.) > As to playing the disc... the cat's meow might be to gain access to an > ELP laser turntable, which doesn't use a physical-contact stylus at > all. No wear... but not cheap nor common.   Not all that effective; it plays every bit of dirt the same as solid groove wall, whereas a stylus will scrape the dirt away as it plays.   A stylus will also scrape the wall away if you get it wrong , so the optical system has the potential to do less damage; but the cleaning process needed before optical playback will probably do as much damage as the stylus. Swings & roundabouts.   -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

John-Del <ohger1s@aol.com>: Dec 15 12:04PM -0800 This has an ESMT logo and F25L32QA on one line and D301W on another. Googling only returns hits for programmers that can read and write to it, but no place to buy and no info for a sub. Anybody have any ideas? Even Alibaba returns zero hits (odd).

Jeff Liebermann <jeffl@cruzio.com>: Dec 15 09:34AM -0800 On Tue, 15 Dec 2015 08:42:08 -0800 (PST), thekmanrocks@gmail.com wrote:     > I can't stand ketchup in or on anything, because of the vinegar in >it. Eat it if you want to, but keep that garbage away from me. It makes >me violently ill. "   Make your own vinegar-less ketchup: <https://maggankruger.wordpress.com/2007/10/19/vinegar-less-homemade-ketchup/> I've never tried it but it looks interesting.   -- 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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