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Amanda Riphnykhazova <licensedtoquill@gmail.com>: Dec 05 10:03AM -0800 Does anyone know if there is a way of ejecting the cassette from this CD cassette player without connecting the power please?   Or do I have to pull the whole thing to bits?

RobertMacy <robert.a.macy@gmail.com>: Dec 06 06:10AM -0700 On Fri, 05 Dec 2014 11:03:15 -0700, Amanda Riphnykhazova   > Does anyone know if there is a way of ejecting the cassette from this CD > cassette player without connecting the power please?   > Or do I have to pull the whole thing to bits?   Don't know your specific, but on mine,I'd WANT to take some of it to bits. Just to inspect that removing the cassettee does not wind the tape everywhere inside. Last time I did this, I had to pull the unit slightly apart to gain access to the little wheels inside then manually turn those little wheels until the cassette walked its way out.

Phil Allison <pallison49@gmail.com>: Dec 05 01:08PM -0800 > Squealing. More volume, more squealing. Quite annoying.   > Pretty obvious it needs filters.   ** Main filter caps ? Not bloody likely.     > Can't seem to find service info on the thing though.     ** How odd. It's an utterly obscure make and a looks like a shit awful pile of Italian junk.     > Actually I am doing music equipment now, amps, mixers etc. and am not actually finding as many bad caps as in brownwares.   ** No fooling. More bad solder joints etc.   ** Yep, music equipment gets transported a lot and subjected to intense vibrations.   > At first I figured this lil thing has to be class D, but a post on the net alludes to it using LM3866 which is not.   ** Yes, I found that post.   LM3886s can deliver about 60 watts into 4 ohms so that dos not tally with the 200wpc rating.     Who knows right now ? At this point though, both channels are doing it so I am leaning toward the PS.   ** Bad multipin connections and cracked solder are far more likely culprits.     As small as this thing is, I will probably have to search Digikey for good enough, snall enough caps for it.   ** Drivel.   > Seriously though, right now I am concerned about getting in there without killing the patient. Anyone have one of those things apart ?   ** Looks like the piles of shit were never retailed outside of Italy - most Google hits are in Italian or Greek.   Music gear, once sold, tends to travel all over the place and way beyond any support networks that exist. Owners never understand this and expect miracles from service techs, performed while they wait and imagine peanuts is sufficient reward.       .... Phil

jurb6006@gmail.com: Dec 05 09:55PM -0800 >"LM3886s can deliver about 60 watts into 4 ohms so that dos not tally with the 200wpc rating. "   That was only an internet post somewhere. I should have spekled out I did not give it much creedence. not make sense, 200 watts from 30 watt chip. Of course them Italianas well soma timesa you never really a know...   It might be 200 watts Peak Insttantaneous Power If Lightning Strikes, which was a popular form of rating aftermarket car stereos until me and the boysa showed up in town and showed them what 100 watts was. but that ws a long itme ago. ;Enough drivel, I do not want to wear your snippers out.   this is pretty straight up here, the more loudness comes out of it, the more squeal at about seems maybe 6 K.   I guess I'll fuck with it Monday. Maybe. I could set it aside and they won't care.   And THEN, yesterday (was off today) god damn fucking Ampeg, little wonder ampeg. Has SMPS, pretty sure class D, VERY small. Bows the breaker/fuse in the wall at plugin.   the fuckheds used too long screws for the little rubber feet on the bottom and it caused a short across the power switch wires.   Damn. Where the fuck ere the engineers ?   Whatever. I also have to figure out the debauchery involved with that Fender or whatever, Chorus thing. Someone changed that pot. W H Y ? the fuck would go wrong wth that ? I smell a leaky, not leaking electrolyte, not juicing up the boarrd with its wondervul acid and shit, but electrically leakey. Right around an oscillator that is supposed to run at a low frequency, OR perhaps a higher one hetrodyned... dunno.   Problem here is like anytime you follow someone else. fucking don't know if they were right and the part is wrong, if they were wrong and the part is right, or what.

etpm@whidbey.com: Dec 05 11:16AM -0800 >You must be young enough that the 'satisfaction' of repairing it has value but you'll get over it. Personally I replace power supplies but replace caps on motherboards to get going again. Repair the things that are hard to replace.   >Also there are nasty Voltages in the power supply but none on the mobo.   >G² I can also just grab a cap out of my box of caps. I guess 58 is probably young enough 'cause I'm still getting satisfaction from fixing and building things. I think by the time I get over it I'll be ashes. Cheers, Eric

Michael Black <et472@ncf.ca>: Dec 05 06:42PM -0500

etpm@whidbey.com: Dec 05 04:32PM -0800 >because they can follow detailed instructions that someone else has >written down for them.   > Michael Well Michael, I guess you're right. I don't know a lot about electronics but I can diagnose stuff. I tried to keep the subject header short which is why it was ambiguous. You are also correct that repair can be just unplugging (or unsoldering) a component or a whol system of parts, like the complete power supply. Since I donm't know a whole lot about electronics I asked here for information that would help me diagnose the bad part or device. Probably I should have posted the question in the basic electronics group too. In the end though I though Jamie was being a little flippant. I felt my reply was a little flip too. Now it has gotten out of hand. A more appropriate reply from me would to have asked Jamie if he was being flippant. If he wasn't then his answer would have been what he thought I was capable of, not an unwarranted conclusion. Cheers, Eric P.S. This weekend I will attempt to find the bad cap, unsolder it and replace it with a new one. If that doesn't work then it's time for Jamie's solution.

"Michael A. Terrell" <mike.terrell@earthlink.net>: Dec 06 12:01AM -0500 > You can buy a 500 W power factor corrected supply from Newegg for $40 and THEN get a $15 rebate. Buying good caps to redo your old supply will run $5-$10 and we haven't added the value of your time. Add another $5-$10 for a new cooling fan and you see how they are disposable.   > You must be young enough that the 'satisfaction' of repairing it has value but you'll get over it. Personally I replace power supplies but replace caps on motherboards to get going again. Repair the things that are hard to replace.   > Also there are nasty Voltages in the power supply but none on the mobo.     I always seem to need odd form factor power supplies, and they aren't $25.   -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.

Phil Allison <pallison49@gmail.com>: Dec 05 01:59PM -0800 > No chorus.   ** The chorus effect ( similar to Leslie) is created in the air around the amp by having two channels and two speakers, one with no effect applied and the other with a varying time delay.   If one channel or speaker is dead, you will hear no effect.   Same scheme used in the many Roland JC120 amps.       > It is pretty sure that the LFO (oscillator) is not working. When you adjust the depth pot there is a change in the sound which indicates the variable filters, VCAs whatever are working.   ** Pretty sure it is a bucket brigade IC that does the job.     .... Phil

mroberds@att.net: Dec 06 04:52AM > ** Pretty sure it is a bucket brigade IC that does the job.   Page 4 of the PDF schematic that jurb posted does indeed show a Panasonic bucket-brigade chip and its associated clock driver. (U13 and U18... just left of center, under the "CHORUS BIAS ADJUST" pot.) The parts list says these are MN3007 and MN3101 respectively. Datasheets are available online at the usual suspects.   The only reason I know about these is that about 10-15 years ago, I built an "echo box" using chips from that series, out of plans from a book. If I remember right, the clock driver gives you a couple of clocks with a certain phase relationship (quadrature or 180?), which you then feed to the bucket-brigade chip itself. In that series, I think there was just one clock driver chip, and various bucket-brigade chips available with different numbers of buckets. At the time, Digi-Key carried them, but I'm pretty sure they are now NLA new.   The schematic shows what the clocks are supposed to look like. If they aren't there, you might be able to fake them with a function generator to see if the bucket-brigade chip itself is working.   Matt Roberds

rev.11d.meow@gmail.com: Dec 05 07:38PM -0800 http://live.sysinternals.com/   enjoy

rev.11d.meow@gmail.com: Dec 05 07:54PM -0800 AutoRuns is your friend here.   http://technet.microsoft.com/en-us/sysinternals/bb963902   Introduction   This utility, which has the most comprehensive knowledge of auto-starting locations of any startup monitor, shows you what programs are configured to run during system bootup or login, and shows you the entries in the order Windows processes them. These programs include ones in your startup folder, Run, RunOnce, and other Registry keys. You can configure Autoruns to show other locations, including Explorer shell extensions, toolbars, browser helper objects, Winlogon notifications, auto-start services, and much more. Autoruns goes way beyond the MSConfig utility bundled with Windows Me and XP.   Autoruns' Hide Signed Microsoft Entries option helps you to zoom in on third-party auto-starting images that have been added to your system and it has support for looking at the auto-starting images configured for other accounts configured on a system. Also included in the download package is a command-line equivalent that can output in CSV format, Autorunsc.   You'll probably be surprised at how many executables are launched automatically!

Phil Allison <pallison49@gmail.com>: Dec 05 03:01PM -0800 Hi,   some of you will have seen this famous powered speaker since it has been around for about 18 years. Tens of thousands must have been sold and it spawned numerous clones. The original is better made than most others with a hefty 12 inch woofer and a 45mm diaphragm compression horn. The amp module is particularly solidly built with generous heatsinking and so no need for a fan.   Inside are two, discrete component power amps of 300W and 60W rating. The 300W amp has four power rails for high efficiency of plus and minus 80 & 40 volts.   Both power amps are DC rail fused and have VI limiting to protect output devices in case of driver failure. Both amps have power limiting too, which reduces the output level after short period of full drive to prevent overheating the woofer and horn driver's voice coils.   So they thought of everything - right? Nope.   Both amps are direct coupled to their respective loads with no protection in case of large DC offsets. Both amps use one half of the same dual op-amp as input gain stages - also direct coupled to the rest of the amp.   Failure of one of the 15V rails that supply the op-amp sends both amp's outputs hard over to one of the 40V rails. A few seconds later, the woofer's voice coil and the horn diaphragm are burnt and destroyed.   In the example on my bench, it looks like an intermittent solder joint in the feed to the -15V supply did the job. The amps test just fine.   One 10uF bi-polar cap would have saved the horn diaphragm and a simple triac crow bar would have saved the woofer. A couple of dollars worth of components.       ... Phil

JC <Chipbee40_SpamNo@yahoo.com>: Dec 05 02:03PM -0500 >> generator. Unlike days of old when such info was available, the >> manufacturers only give it to those purchasing (or about to purchase) a >> large number of their devices today.   Hi Ken,   There is a full schematic for your clock gen at   http://wenku.baidu.com/view/1207127f31b765ce05081419.html   About 2/3 down the webpage there is a document Clock Gen Silego SLG8LP625TTR, it shows bad on the web but if you save it and open it its very clear to read   posters here may not realize this is a one piece computer and probably worth repairing.   http://h10025.www1.hp.com/ewfrf/wc/product?product=4007375&cc=us&dlc=en&lc=en   An image of the board is here :   http://www.ebay.com/itm/HP-TouchSmart-300-Series-Motherboard-APP78-CF-510762-002-Test-Ok-/261300571054?pt=Motherboards&hash=item3cd6ba4bae   JC

Ken <Ken@invalid.com>: Dec 05 02:34PM -0600 JC wrote:   > An image of the board is here :   > http://www.ebay.com/itm/HP-TouchSmart-300-Series-Motherboard-APP78-CF-510762-002-Test-Ok-/261300571054?pt=Motherboards&hash=item3cd6ba4bae   > JC   Thanks for the info, that is MUCH more than I had. It may not tell me what is wrong, but it just might.

"David K. Bryant" <dbryant_94585@earthlink.net>: Dec 05 10:06AM -0800 > I was > wondering, is there one particular part in that assembly which causes the > failure?     The electromagnetic clutch on the end of the shaft. Failure modes:   not engaging always engaged slipping   Usually the latter. This is evident when the paper feeds but not all the way thru. Paper Jam error message often means that the paper failed to reach a sensor at the right time.     --- news://freenews.netfront.net/ - complaints: news@netfront.net ---

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Ken <Ken@invalid.com>: Dec 04 08:17PM -0600 > If it does beep it is probably not the clock generator, provided you > are looking aty the right chip. What's the number anyway ? Maybe I'll > have a go at getting some info on it.   Sure did try it without RAM. Even tested the RAM in another computer. The clock generator is a SLG8LP625T Thanks.

stratus46@yahoo.com: Dec 04 08:56PM -0800 On Thursday, December 4, 2014 5:04:50 AM UTC-8, Ken wrote: > stratus46@yahoo.com wrote: <snip> > Searching the web, I found others with the same type of problem on the > same model of computer. That does not mean there is a common problem, > but it does mean I am not alone.   The thing to remember about ESR meters is that they can be fooled by parallel ceramic bypass caps so it can read good when it is in fact bad. If it reads bad it likely is. Bulging is a good indicator and ruptures have likely sprayed acid around the board.   I started using solid polymer caps instead of 'lytics on mobos at work and they're doing well. My 4 newer machines at home are all polymers and no 'lytics. I expect no problems before obsolescence.   IF you decide to change caps, go for the highest ripple current / lowest ESR and stay away from cheap junk.   G²

jurb6006@gmail.com: Dec 05 07:18AM -0800 >"Sure did try it without RAM."   OK, that was the specific information I wanted. the RAM is cleared as well as a possibly corrupted RAM controller. Sometimes those things take a virus or a cosmic ray or something and it needs to reset completely to straighten it out. (not kidding anymore about the cosmic ray, I recently read an article on exactly that corrupting memory)   I didn't find the sheet on that chip. This is one of those things that would probably require emailing Silllyonics or whoever made the thing and all that. However it does seem there are suppliers. What is the case style ? Is it something that doesn't take a million dollar rework station to change ? (like a BGA) If it's not that bad you might just try popping one in. Also if there is a crystal nar the thing change that as well, in fact maybe change that first as it is easier. If you can find it, if it is not built into the IC, if if if, of course.   And as stra...@yahoo said, make sure about the caps. hat I ddo sometimes is to determine which are in the same bank. Of course all the grounded sides read continuity, but when you get continuity on the other (usually +) lead, those are all in one bank. Then for testing purposes I just put in one. I don't even trim the leads, I leave them long and just see if the damthing works. If it does then I start changing the bunch of them. One hting about oscillators, if the power going to it isn't well bypassed it might just not work. Depends on how it is configured.   I assume since you said it is not clocking that you have seen AOME DC on the pins. If all the pins have 0V it is kinda obvious. (I run the scope in DC mode for things like this for reasons like that, then I know already)   This now depends on how good the board is. If you can get the same model generic you MIGHT be able to migrate the OS to it and avoid a reload, but I cannot say if it would have to come from Overpriced.com, err I mean HP. They might not have made the board. Like this Dell I got in the boneyard, ECS motherboard. Thought you were buying a good PC from a reputable source ? Well ECS is about ½ step down from Foxconn, meaning elcheapo. I would have replaced this ECS if I could get a fair price on it, which I consider to be about twenty bucks. I would get a decent Gigabyte or something but I wouldn't be able to reregister the OEM Windows 7 to it. So to the boneyard with it. Your HP is probably the same deal, you'll need a copy of Windows if you change it to a totally different type of board. (of course with Linux you wouldn't have that problem but that is beside the point)   Yup, caps, chip and crystal and if that doesn't do it, it is probably for the boneyard. You still have drives and a PS and all that right ?

Ken <Ken@invalid.com>: Dec 05 10:13AM -0600 > Yup, caps, chip and crystal and if that doesn't do it, it is probably > for the boneyard. You still have drives and a PS and all that right > ?   All of what you say about the project is true. I have spent more time on it than it is worth, but I am a persistent person who believes "the answer is out there." I think I shall look for a scrap computer of the same model that has a good MB but the rest of it is NG. A new MB costing $200-300 is out of the question.   Finally, like you said about there being no voltage on the other pins of the clock generator: It would be obvious as to why it did not work. There were DC levels and the cap next to the chip was at the 3.3v supply the chip needed. I thought someone might have some source of info about the clock generator that would confirm my belief that it should be free running. Thanks to you and the others for their comments.

jurb6006@gmail.com: Dec 05 07:42AM -0800 No chorus. The rate pot has been changed, and it appears successful but messy. It is a slightly different pot but seems right enough I would think. It is a 100K. On it I have a negative DC voltage, varies at the wiper.   I do not know if the pot was bad, maybe the last guy put in the wrong one. Or maybe it is the right one and he erroneously replaced it but it didn't fix it. I have no way of knowing this.   It is pretty sure that the LFO (oscillator) is not working. When you adjust the depth pot there is a change in the sound which indicates the variable filters, VCAs whatever are working.   One thing would be nice is a print. I have one but it is poor quality.   https://dl.dropboxusercontent.com/u/29948706/fender_power_chorus.rar   A better one would help, in fact probably ANY print of that section in an amp using the same chorus circuit.   Thanks. I am not as adept at reverse engineering as I used to be. Blind in one eye and can't see out the other. In my heyday some would joke that I could do this with my eyes closed. And now... LOL

N_Cook <diverse@tcp.co.uk>: Dec 05 03:48PM > https://dl.dropboxusercontent.com/u/29948706/fender_power_chorus.rar   > A better one would help, in fact probably ANY print of that section in an amp using the same chorus circuit.   > Thanks. I am not as adept at reverse engineering as I used to be. Blind in one eye and can't see out the other. In my heyday some would joke that I could do this with my eyes closed. And now... LOL   Is this a "digital" pot the wiper feeds an ADC ?

jurb6006@gmail.com: Dec 05 07:31AM -0800 Squealing. More volume, more squealing. Quite annoying.   Pretty obvious it needs filters. Can't seem to find service info on the thing though. I think I can do it without but I would really like to see how it comes apart before tearing in to it. It has the flip top like a laptop and you know how those can be. I don't want to screw it up, rip the main ribbon to the lid or anything like that.   Actually I am doing music equipment now, amps, mixers etc. and am not actually finding as many bad caps as in brownwares. More bad solder joints etc. Is there ac chance that's the problem here ? If I had history on it, if the problem used to be intermittent, great.   At first I figured this lil thing has to be class D, but a post on the net alludes to it using LM3866 which is not. Who knows right now ? At this point though, both channels are doing it so I am leaning toward the PS. As small as this thing is, I will probably have to search Digikey for good enough, snall enough caps for it.   Seriously though, right now I am concerned about getting in there without killing the patient. Anyone have one of those things apart ?   Thanks.

KenO <kenitholson@yahoo.com>: Dec 04 01:14PM -0800 Have a fully discharged Nokia BL-5J 1430 mAh 3.7 Battery that would like to safely test for charge retention.   Did some forum searching and found some general info.   Did not find anything concerning:   1. how to test if the battery fuse and protection circuit is intact. Just guessing that if infinite Ohms something is blown but have no idea what the normal Ohms should be.   2. Use another battery to try to charge the Nokia to get it above the charger cutoff point?   Hope someone has solved this problem and would like to share any tips.   Googled and found "Li-ion should never be discharged too low, and there are several safeguards to prevent this from happening. The equipment cuts off when the battery discharges to about 3.0V/cell, stopping the current flow. If the discharge continues to about 2.70V/cell or lower, the battery's protection circuit puts the battery into a sleep mode. This renders the pack unserviceable and a recharge with most chargers is not possible. To prevent a battery from falling asleep, apply a partial charge before a long storage period."   Also found by another Ken who does not want to share his method "On February 4, 2011 at 2:21pm Ken wrote: The article mentions how dangerous it is to attempt charging cells that have been @<1.5v for just a few days. Well, that has not been in agreement with my experience. I occasionally salvage discarded Li-ion laptop battery packs...disassembling them to harvest the 18650's for personal r/c and flashlight use. I commonly pull cells that are totally flat: 0v, sometimes even with polarity reversed by a few millivolts. In addition, some of the battery packs I ripped into were prehistoric by lithium chemistry standards (10 years+). More often than not all cells would recharge to their FULL original rated capacity and perform as new. I always test each cell individually with my iMAX B6 charger, manually putting them through at least a couple 500mA to 1Amp discharge/charge cycles. I have *never* experienced any safety nor reliability issues to date. I would also like to brag of having had success restoring substantial capacity to the occasional cells that truly were worn. I will never share my method_IT'S MINE !_do not ask. ...Additionally, that procedure IS potentially dangerous and requires mandatory attentive supervision. I suppose I've been laughing all the way to the battery bank. I know, horrible joke!" http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries   Thanks   Ken

mike <ham789@netzero.net>: Dec 05 12:05AM -0800 On 12/4/2014 1:14 PM, KenO wrote:   > Thanks   > Ken   No idea about your battery, but here are some of the issues. It probably has a protection circuit. If it has been discharged below threshold, it's turned off and cannot be turned on externally. You'll see zero volts and high ohms.   Disclaimer: What follows is for educational purposes only. DO NOT DO IT! IT's unsafe.   IF you take the battery apart, you can get past the circuit board and connect directly to the cell, you can charge it. If I were to ever do this unsafe procedure, I might start with 100 mA charge current voltage limited at about 3.7V depending on the exact chemistry involved. Do NOT get in a hurry...do not set it up and go away...watch it, through your safety glasses, for any signs of overheating. You need a laboratory supply with precise control of the current and voltage limits. DO not rely on some marking on a wall wart. NEVER, EVER TRY TO CHARGE ONE BATTERY FROM ANOTHER BATTERY! You risk setting yourself on fire. The protection circuit is there for a reason. I'd put it in a metal pot with a lid so I'd have a handle to use to carry it outside if it catches fire. THIS IS NOT A SAFE PROCEDURE.   At this point, I might try charging it in the phone.   Sometimes, the protection circuit will NOT reset. If it's still dead, give up, you've done all you can do.   Even if you're successful, you are still at risk. Maybe your phone will catch fire weeks from now.   Bottom line, go buy a new battery. They're much cheaper on ebay than the cost of a hospital visit or a burned-down house.

Tim R <timothy42b@aol.com>: Dec 05 06:46AM -0800 I came across an interesting thread on a flashlight battery explosion.   http://www.candlepowerforums.com/vb/showthread.php?120888-ROAR-of-the-Pelican-(CR123-Explosion-during-use-firsthand-account)   Read down to page 5, where the delayed effects of HF poisoning hit the victim. I understand he has never recovered fully.

etpm@whidbey.com: Dec 04 09:55AM -0800 On Tue, 2 Dec 2014 16:44:10 -0500, "Maynard A. Philbrook Jr." >> Eric   >Try replacing the Power Supply!   >Jamie You did notice that this is an electronics REPAIR group, right? Eric

Michael Black <et472@ncf.ca>: Dec 04 01:58PM -0500

"Maynard A. Philbrook Jr." <jamie_ka1lpa@charter.net>: Dec 04 06:45PM -0500 In article <dv718ade9jmos0oe8jikcns7d3erdhoidm@4ax.com>, etpm@whidbey.com says...   > >Jamie > You did notice that this is an electronics REPAIR group, right? > Eric   Sure did and if you knew what you were talking about you would know that cost of labor investigating internals of a power supply over simply just replacing it has a broad dollar value. Labor is expensive but the cost of a replacement supply or just simply plugging in a test unit is much cheaper   Next time, think , think, and think again before opening the trap.   Jamie

etpm@whidbey.com: Dec 04 04:32PM -0800 On Thu, 4 Dec 2014 18:45:12 -0500, "Maynard A. Philbrook Jr." >much cheaper   > Next time, think , think, and think again before opening the trap.   >Jamie Since I'm going to repair it I have decided the labor is worth it. I suppose I should have said that I was going to repair this power supply. I did not say if I had looked in the power supply. I should have because I did. But it seems like I did not look closely enough. This weekend I'll take another look and hopefully find a bulging cap that I can replace. Eric

stratus46@yahoo.com: Dec 04 09:07PM -0800 > This weekend I'll take another look and hopefully find a bulging cap > that I can replace. > Eric   You can buy a 500 W power factor corrected supply from Newegg for $40 and THEN get a $15 rebate. Buying good caps to redo your old supply will run $5-$10 and we haven't added the value of your time. Add another $5-$10 for a new cooling fan and you see how they are disposable.   You must be young enough that the 'satisfaction' of repairing it has value but you'll get over it. Personally I replace power supplies but replace caps on motherboards to get going again. Repair the things that are hard to replace.   Also there are nasty Voltages in the power supply but none on the mobo.   G²

Tim R <timothy42b@aol.com>: Dec 05 06:11AM -0800 > You must be young enough that the 'satisfaction' of repairing it has value but you'll get over it. Personally I replace power supplies but replace caps on motherboards to get going again. Repair the things that are hard to replace.   > Also there are nasty Voltages in the power supply but none on the mobo.   > G²   There is some satisfaction in the learning process itself though.   I hadn't realized at first but now obviously this is a PC but not a laptop. So I don't know if my observation applies here at all. But given our history with the kids's school laptops, the power supply and the power jack seem to be weak links. We've gone through a number of replacement wallwarts or equivalent, and have had several where the power jack connection eventually fails.   I guess there's no point making them bulletproof when the PC is obsolete in a few years, but it sure is annoying to have an otherwise workable machine unusable because you can't power it up.

Phil Allison <pallison49@gmail.com>: Dec 04 05:21PM -0800 Arfa Daily wrote:   > In my workshop, I have four four-drawer filing cabinets absolutely > jam-packed with service manuals that I have collected over more than 40 > years in the business.   ** Wow, I have hardly any after 40 years in the same business.   Here in Australia, service manuals for most pro audio products have long been hard to get and/or cost real money. The info (other than a schematic) provided in the vast majority is so poor as to be worthless. I am thinking of manuals from Crown, Yamaha, QSC, Phase Linear and others.   One problem is that the folk who write these manuals are never service techs. Often the product designer is given the job or some one associated with the design team who picked the short straw. If you have never made your living doing bench servicing, how in hell can you expect to advise those that do ?   Another problem is that at the time of writing, no actual products have been sold so none of the product's design faults or reliability issues have come to light. Most manufacturers are unwilling to put anything potentially damaging to their reputations into print in any case - lest a customer might see it!   I needed a schem for the EV 2.0kW power amp a few year back and was offered a full manual for $20 from the local EV agents. When it arrived it was a joke. All the schematics were drawn without dots - you simply could not tell if any two lines that crossed at right angles were joined at that point or not !!   I rang to complain and was immediately told they are all like that - sorry.   The manual for the Crown PSA-2 amplifier has procedures for testing the amp after repairs have been done. The final test is for the VI limiter and involves driving each channel at 20V rms into a 1 ohm load. What the manual writer did not take into account is that if the VI limiter circuit *fails* to operate correctly, that channel will instantly blow up! Hell of a test - eh.   Manuals for many QSC amps ( USA series etc) give details on connecting an output transformer to convert the amps for 70V line operation. QSC even sell a 300W transformer for the job. But don't you dare do it !   The current limiting scheme QSC use is a real oddball and works only with resistive loads. Soon as a low or subsonic frequency comes along, the iron core in the output tranny saturates and instantly blows up the amp. One of my customers found out the hard way after and simultaneously destroying four brand new USA900s.   Over the years, I have had to evolve my own methods of safely bench testing amplifiers, before and after repairs, including non invasive setting of bias levels and checking VI limiters for correct operation into reactive dummy loads.   Far as I am concerned, Service Manuals are mainly for light entertainment reading.     .... Phil

ggherold@gmail.com: Dec 04 10:00AM -0800 On Monday, December 1, 2014 11:26:20 AM UTC-5, Don Kuenz wrote:   > ( \_/ ) > (='-'=) Don Kuenz > (")_(")   This is fun, http://www.dansdata.com/goop.htm   How about some vegemite? :^)   George H.

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"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 04 01:42AM In my workshop, I have four four-drawer filing cabinets absolutely jam-packed with service manuals that I have collected over more than 40 years in the business. The thing is, that I almost never go to them any more. My first stop is almost always the archive of downloaded manuals on the computer, and if the one I want is not there, then online to one of the excellent archives to be found there, to download it. And if I can't find one, then the item is probably not worth the fixing time anyway.   So, even though it's been a bit heart-wrenching, I've started ditching all the old paper manuals, with a view to getting rid of three of those cabinets, and winning back the space. As well as doing this, I have also been sorting out the many many cabinets of small spares, and been seriously rationalising what is kept. It's really hard, and I keep thinking "I'm gonna need that next week" as something else goes in the bin. But at the same time, it is also sort of 'invigorating' to be restoring some order and tidiness to the workshop.   Has anyone else been through this process and felt better for it at the end, or am I just going to regret doing it for years to come ... ?   Arfa

John Robertson <spam@flippers.com>: Dec 03 06:23PM -0800 On 12/03/2014, 5:42 PM, Arfa Daily wrote:   > Has anyone else been through this process and felt better for it at the > end, or am I just going to regret doing it for years to come ... ?   > Arfa   Well, I have about ten filing cabinets in my shop and while a reasonable percentage is online, most of it is not. So I slowly scan them as we have time and add to our internal library.   I have no intention of dumping the paper, it is my archive.   John :-#)#   -- (Please post followups or tech inquiries to the 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."

Jeff Liebermann <jeffl@cruzio.com>: Dec 03 07:47PM -0800 On Thu, 4 Dec 2014 01:42:14 -0000, "Arfa Daily"   >Has anyone else been through this process and felt better for it at the end, >or am I just going to regret doing it for years to come ... ?   Yep. I have a similar problem. Most of the "recent" manuals, which means in the 30 years, I've recycled or sold. They're all available in PDF form somewhere. The really old stuff, dating back to the 1960's through 1980's, I'll keep for now, as they're often difficult to find. I've been scanning these as needed, and posting them to various public archives. However, since there's no money in doing this, it's a very low priority for me. Fortunately, I have an easy way to do the scans. One of my customers has a Canon ImageRunner 5000 copier, that will do double sided scan and OCR reads to PDF very quickly. Video of the machine in operation: <http://802.11junk.com/jeffl/crud/CanonImageRunner5000.wmv>   A much bigger problem is how to organize manuals and driver CD's. The recent stuff can usually be found online, but the old stuff is long gone and difficult to find. I have several large boxes full of disorganized CD's, that require a linear search through the mess every time I need something. I think of it as a miniature version of the service manual problem.   About a year ago, I purged my office of floppy disks, keeping only those that I suspected I might need. Since then, I've spent an inordinate amount of time finding images of the one's I tossed. However, I expect that problem to be only temporary, as I'm refusing to work on any antique computers, which also allows me to toss old power supplies, cables, PCB's, etc. That's much easier than running an antique computah warehouse.   I suspect that you'll be quite happy with scanned manuals. There's not as handy as the printed variety, but they do have the advantage of being searchable, which makes them quite superior to printed manuals. If you're scanning to PDF, try: <http://www.tracker-software.com/product/pdf-xchange-viewer> (free) which has a built in OCR reader which can be used to make scanned PDF's searchable.     -- 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

Michael Black <et472@ncf.ca>: Dec 03 11:54PM -0500

Jeff Liebermann <jeffl@cruzio.com>: Dec 03 10:19PM -0800 >turn them into text, while after that certain year, it was done >electronically anyway, so full searches can be done on those later >patents.   Not really. The USPTO has just scans, but if you use Google Patent search, the PDF files were all fed to an OCR reader and are searchable. I just tried some really early patents and they were all searchable. The basic text of the patent, in searchable ASCII, is also available on the Google Patent search pages: <https://www.google.com/patents/> <http://www.google.com/advanced_patent_search> Unfortunately, Google made a mess of the OCR reading on some patents, so don't expect perfection.   For my own devious purposes, I make sure that all my PDF manuals are OCR read and searchable. I then use a text search tool, such as Agent Ransack, to find the manuals or search the contents: <http://www.mythicsoft.com/agentransack> Some manuals arrive in MS Word format, which Agent Ransack can also handle if I enable the "search MS Office format" checkbox.   It's a long way from the paperless office, but it's a lurch in the right direction.   -- 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

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: Dec 04 06:52AM -0600 "Arfa Daily" <arfa.daily@ntlworld.com> wrote in message news:XZOfw.51090$GK1.22488@fx36.am4...   > Has anyone else been through this process and felt better for it at the > end, or am I just going to regret doing it for years to come ... ?   > Arfa   Oh, yes. We have tons of old Hitachi, Sony, JVC, RCA etc vcr manuals, Pioneer crt big-screen manuals, and on and on. Better off just to throw them away. Way back when, they were golden.   I do think that when I retire I can pick a bit of change selling original McIntosh, Marantz, Denon, Kenwood etc audio manuals on eBay.   Even have a collection of old B&O manuals I suspect I could get fairly good money for.   Sign of the times indeed - I mostly use digital copies anymore also. Big 24" monitor on the bench helps the old eyes.     Mark Z.

"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 04 07:56AM -0800 I compulsively collected service manuals -- especially for the Sony products I owned -- and, as you've seen, that collecting came in handy just yesterday.   When I was a kid, the Enoch Pratt Free Library * had volumes of the Rider service manuals, which I sometimes pored over.   I would be cautious about destroying them. You'd probably be better off boxing them, and putting the boxes in a safe, dry place until you find someone who'll give them a good home.   * For those who aren't Baltimorons... The Pratt library was endowed by a wealthy merchant. It was (and probably still is) considered one of the world's great public libraries. It was the first place to go when I had to do research for high school papers.   https://en.wikipedia.org/wiki/Enoch_Pratt_Free_Library

John-Del <ohger1s@aol.com>: Dec 03 03:51PM -0800 On Wednesday, December 3, 2014 10:14:05 AM UTC-5, William Sommerwerck wrote: > gets in the way of it swinging back, so //that's// going to have to come off.   > Nothing is ever simple. I just keep telling myself "It's kaput, so what > difference does it make?"   Morbid curiosity most likely. If you've got time that would otherwise be wasted watching TV, then you'll probably enjoy solving the puzzle more.

"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 04 07:48AM -0800 "John-Del" wrote in message news:3b4738d8-c399-45e9-8a0a-781cad466299@googlegroups.com... On Wednesday, December 3, 2014 10:14:05 AM UTC-5, William Sommerwerck wrote:   >> Nothing is ever simple. I just keep telling myself "It's kaput, >> so what difference does it make?"   > Morbid curiosity most likely.   We like to think we're "smarter" than the equipment we're working on. In this case, though... There's no question the Play button is shorted to ground even when it's not pressed. But... the controls work through a resistor ladder, and the readings I get for the resistors are backwards (eg, the 10K "base" resistor is readable only when the Play button is pressed, though it should be other other way around). This, of course, has nothing to do with the problem (I think), but it drives me crazy.   "Just for luck", I pulled the cable from the main board and reinserted it. I think I'll just put it back together and forget about it. (This problems isn't going to have one of those "It works! It's a miracle!" endings.)   I have spares, and this model (D-FJ75TR) shows up on eBay occasionally at a low price. So it's no big deal.     > If you've got time that would otherwise be wasted watching TV, > then you'll probably enjoy solving the puzzle more.   I have a pile of books worth reading (among others, I'm working my way through LIFE's "The Old West"), and a list as long as my arm of things to update or repair. I'm trying to do one a day, but it's more like two a week. I just blew out a classic Lux amp, so that's risen to the top of my list.   I did watch two Blu-ray movies yesterday, "Gojira" and "42". I was anxious to see the latter, as an acquaintance was in it. TV watching is limited to when I go to bed -- which, in this weather, is fairly early.

Ken <Ken@invalid.com>: Dec 03 11:27AM -0600 chuck wrote: > power supplies but the computer won't boot. The problem is the power > supply. My guess is that the supply fails when current draw increases > on start up.   Replaced the PS, a good thought however. This still leads me back to a clock generator that is not showing any leads moving. The processor cannot begin to function without a clock pulse. My biggest problem is not being able to find any documentation for the processor or the clock generator. Unlike days of old when such info was available, the manufacturers only give it to those purchasing (or about to purchase) a large number of their devices today.

jurb6006@gmail.com: Dec 03 09:07PM -0800 What would be really nice is to find this the problem and then to fix a couple of old ones I have laying around. That would be great because one of them in particular though an XP class board is a really high end one and has some stuff I would like to have. The other is a Dell that an Win 7, hich means it is an adequate conmputer.   But the fact is that almost for sure, when the mobo is found to be at fault, it is usually software. That BIOS shit, it runs in no extended RAM, down at the bottom. Things have advanced a bit but the thing that makes it beep is still a very rudimentary system.   So anyway, did you pull the RAM ?

stratus46@yahoo.com: Dec 03 10:06PM -0800 On Wednesday, December 3, 2014 9:27:56 AM UTC-8, Ken wrote: <snip> > generator. Unlike days of old when such info was available, the > manufacturers only give it to those purchasing (or about to purchase) a > large number of their devices today.   How old is the mobo ? We have some older (5+ year) servers at work that don't run if the caps are bad. Replacing bad caps almost always brings them back up. Computers are very fussy about the power supplies. 'Good enough' rarely is.   G²

Ken <Ken@invalid.com>: Dec 04 06:55AM -0600 > What would be really nice is to find this the problem and then to fix a couple of old ones I have laying around. That would be great because one of them in particular though an XP class board is a really high end one and has some stuff I would like to have. The other is a Dell that an Win 7, hich means it is an adequate conmputer.   > But the fact is that almost for sure, when the mobo is found to be at fault, it is usually software. That BIOS shit, it runs in no extended RAM, down at the bottom. Things have advanced a bit but the thing that makes it beep is still a very rudimentary system.   > So anyway, did you pull the RAM ?   The RAM is good, as I pulled it and tested it in another computer.

Ken <Ken@invalid.com>: Dec 04 07:04AM -0600 > brings them back up. Computers are very fussy about the power > supplies. 'Good enough' rarely is.   > G²   The computer is probably not older than 4-5 years. It has Windows 7 installed and of course is a touch screen unit. The thing that makes trouble shooting difficult today is many (including this one) are "All in one" units and they are not as accessible as they once were. Put that together with the manufacturers not wanting to give out information about the components, and you are often forced into buying a new unit.   For what it is worth, I checked the caps on the MB with my ESR meter. Searching the web, I found others with the same type of problem on the same model of computer. That does not mean there is a common problem, but it does mean I am not alone.

jurb6006@gmail.com: Dec 04 07:44AM -0800 >"The RAM is good, as I pulled it and tested it in another computer. "   Fine and dandy, but did you try firing up this computer with no RAM in it ? It is supposed to beep. If it does not beep that is bad.   If it does beep it is probably not the clock generator, provided you are looking aty the right chip. What's the number anyway ? Maybe I'll have a go at getting some info on it.

gregz <zekor@comcast.net>: Dec 04 07:20AM > (like mica and plastic washers) to isolate it electrically. Years ago it > was more common to find metal backed T0-220s or T0-3s that needed mica or > silicon rubber. Today most semis are encapsulated and only need thermal goo to mount.   I started fixing an amp somebody was trying to fix. Without insulators on the output transistors, it was never going to work.   Greg

bv4bv4bv4@gmail.com: Dec 03 09:24AM -0800 Why is Smiling a Donation? (And smiling to your brother is donation). This is what the greatest Prophet (All Prayers and Peace of Allah be upon him) said and this is what the latest researches are discovering, so let's read .... Researchers have studied about smiling influence on others. They have found that smiling contains strong information that can influence the human subconscious mind! They found that everyone has his particular smile that no one can share with him. Moreover, every smile contains special effect, too. They photographed these smiles and showed it slowly, hence, they noticed some specific movements. Likewise, a person can have more than one kind of smiles, regarding his mental status, what is he speaking about and the person he is speaking to... Some of the most important information of such researches, researches are talking about what you can give to others through the smile, because it is more than giving a material thing for the following reasons: When smiling you can transmit joy to others, which is a sort of donation and which can be the most important. Studies showed that sometimes man may need joy and gladness more than food and drink. Also, that joy can treat many diseases starting by heart problems. Through the smile you can transmit information to others very easily, because a word with a smile has more influence on the brain. Magnetic resonance imaging has shown that expression influence changes too much with a smile. The expression is the same , however, the influenced brain parts differ according to smile type accompanying this information or this expression. You can calm an atmosphere stain of a given situation with a soft smile. This cannot be done with money. Hence, smile is worthier and more important than money. So, the less you can give to others is smile donation. Smile and recovery: Many doctors have noticed smile influence on recovery. Therefore, some researches declare that the doctor's smile is a part of the treatment! Then, giving a smile to your friend, your wife or your neighbor, you are giving them a free remedy prescription without feeling, and this is a kind of donation. For these reasons and others, smile is considered as a sort of donation, giving and generosity. And now dear reader, do you realize why did the prophet of compassion (All Prayers and Peace of Allah be upon him) say: (and smiling to your brother is donation)!! -------------------- By: Abduldaem Al-Kaheel www.kaheel7.com/eng http://www.kaheel7.com/eng/index.php/legislative-miracles/193-why-is-smiling-a-donation- Source: · Smile -- And The World Can Hear You, Even If You Hide, www.sciencedaily.com, Jan. 16, 2008. Thank you

John Robertson <spam@flippers.com>: Dec 03 11:09AM -0800 > Why is Smiling a Donation?   Why is a good bowel movement a donation?   Is it not true that you say the Prophet is claiming that things humans do is a donation?   If so, then a good dump is certainly right up there.   As is a nice kiss, dancing, admiring a beautiful woman (or man if you are so inclined), breathing (try doing with out that for long!), a good sleep, good sex (consenting adults), and so on.   John :-#)#   -- (Please post followups or tech inquiries to the 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 03 03:48PM -0800 On Wednesday, December 3, 2014 2:09:28 PM UTC-5, John Robertson wrote: > (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."     John you smooth talker you... I was all set to become a bomb making, throat cutting abuser of women and children follower of the prophet but you've changed my mind.

Ken <Ken@invalid.com>: Dec 03 05:58PM -0600 John-Del wrote: >> www.flippers.com >> "Old pinballers never die, they just flip out."   > John you smooth talker you... I was all set to become a bomb making, throat cutting abuser of women and children follower of the prophet but you've changed my mind.   THAT is FUNNY!!!!

John Robertson <spam@flippers.com>: Dec 03 06:21PM -0800 On 12/03/2014, 3:48 PM, John-Del wrote:   > John you smooth talker you... I was all set to become a bomb making, throat cutting abuser of women and children follower of the prophet but you've changed my mind.   As with Christians, Buddhists, Sufi, (insert your favourite religion here) only a tiny minority of Muslims are bomb making, throat cutting etc. lunatics.   Most are peaceful nice folks who make good neighbours.   The crazies? Well stop them like any rabid animal. But the fact that a few are unsane doesn't mean all of them are. And don't forget that Fox News is in business to make money - look up the Spanish American War and see what part Randolph Hearst had in creating that conflict.   Back to repairs!   John :-#)#   -- (Please post followups or tech inquiries to the 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."

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