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MNMikeW <mnmiikkew@aol.com>: Aug 13 07:42PM What, chemically, is that whiteish crumbly powder on bad batteries?   We all have seen it, and most of the time you can just brush it off, but I have it on a device deep inside that I can't get a brush on without breaking stuff.   I'd like to use a solvent (I already tried water but I want to do a better job) that dissolves the stuff so knowing the chemistry might help.   Do you have any idea what the chemical composition of that stuff is?

Thane <m741@ix.netcom.com>: Aug 13 02:52PM -0500 On Thu, 13 Aug 2015 19:42:16 +0000, MNMikeW wrote:       > Do you have any idea what the chemical composition of that stuff is?   It's a mixture of potassium hydroxide and potassium carbonate.   Check this article.   http://www.thenakedscientists.com/HTML/questions/question/1000207/   Thane

John Robertson <spam@flippers.com>: Aug 13 12:52PM -0700 On 08/13/2015 12:42 PM, MNMikeW wrote:   > I'd like to use a solvent (I already tried water but I want to do a > better job) that dissolves the stuff so knowing the chemistry might help.   > Do you have any idea what the chemical composition of that stuff is?   Potassium Hydroxide - an alkaline (Alkaline batteries after all). Wash off with a mild solution (50/50) of white vinegar and water, scrub, and rinse with clean water carefully.   http://flippers.com/battery.html   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."

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Aug 10 09:05AM +1000 On 10/08/2015 7:13 AM, Tim R wrote:   > I just looked it up, the weight is 11.4 kg. The date is given as > 1981, which may make it almost 35 years old.   > I haven't opened it up to look yet.   **I guess our definition of "heavy" is very different. 11.4kg is not heavy. 50kg is heavy. Either way, your Onkyo is an attractive, retro-styled receiver. Keep an eye on eBay for typical selling prices. That will provide an indication as to the viability of repair. Your first option should be to obtain a service manual, or schematic and perform the usual fault-finding process.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

all2001@spambog.com (Wolfgang Allinger): Aug 10 07:31AM -0300 On 10 Aug 15 at group /sci/electronics/repair in article 55c8844e$0$3646$4c5efc6d@fastusenet.org >driver IC (STK3062).   >New old stock replacements are rare and Chinese counterfeits are >likely to perform poorly if at all.     Some amplifier have Relais just to suppress the PWRon `plopping`.   Find out, if the Onkyo has it.   The contact (material) often is bad selected, designed, dirty or broken...   Knocking these Relais while powered with the grip of a screwdriver from different direction just to see if gives some scratching noise.   Some relais may be opened easily and press/move/clean the contacts. Or find out the layout position of the contact and bridge them for the faulty channel.     Saludos (an alle Vernünftigen, Rest sh. sig) Wolfgang   -- Wolfgang Allinger, anerkannter Trollallergiker :) reply Adresse gesetzt! Ich diskutiere zukünftig weniger mit Idioten, denn sie ziehen mich auf ihr Niveau herunter und schlagen mich dort mit ihrer Erfahrung! :p (lt. alter usenet Weisheit) iPod, iPhone, iPad, iTunes, iRak, iDiot

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: Aug 10 06:00AM -0500 "Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message news:d2q4njFrdq6U1@mid.individual.net...   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   The OP has no technical expertise. Other than the 4 amp fuses on the rear of the unit, his chances of fixing it himself are low.   Having said the obvious, if there is sound at that channel of the volume control, the fault is most likely an output IC (STK0050II) or driver IC (STK3062).   New old stock replacements are rare and Chinese counterfeits are likely to perform poorly if at all.     Mark Z.

"Shaun" <stereobuff07@gmail.com>: Aug 10 01:24PM -0500 "Mark Zacharias" wrote in message news:55c8844e$0$3646$4c5efc6d@fastusenet.org...   "Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message news:d2q4njFrdq6U1@mid.individual.net...   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   The OP has no technical expertise. Other than the 4 amp fuses on the rear of the unit, his chances of fixing it himself are low.   Having said the obvious, if there is sound at that channel of the volume control, the fault is most likely an output IC (STK0050II) or driver IC (STK3062).   New old stock replacements are rare and Chinese counterfeits are likely to perform poorly if at all.     Mark Z.     If it has Output ICs instead of discrete components; just throw it out, they are not worth fixing any way.   I would have thought that on older model Onkyo would be discrete.   Shaun

Cydrome Leader <presence@MUNGEpanix.com>: Aug 10 06:12PM > It's an Onkyo TX-3000. I bought it for $5 at a thrift store years ago, and still remember carrying it to the car several blocks away.   > I just looked it up, the weight is 11.4 kg. The date is given as 1981, which may make it almost 35 years old.   > I haven't opened it up to look yet.   Start simple.   Check the speaker fuses on the rear. Swap good for bad to make sure the amp module isn't also blown if that's an issue.

"Gareth Magennis" <sound.service@btconnect.com>: Aug 12 06:08PM +0100 "Arfa Daily" wrote in message news:58Mwx.110054$1h.1790@fx25.am4...   Anyone got the schematics for a Crown XLS5000 ? I'm most interested in the board that the mains comes in to. There's a bloody great disc something inside a big lump of heatshrink, and serious flames shoot out of it before every trip and fuse in the workshop goes out ...   If I bring it up on the variac, I can't get beyond about 20 volts before the poor thing is jumping off the bench, so there's a good short on there somewhere. I initially thought that the disc might be a big VDR that was short, but looking up the part number on the second one that's on there for the other half of the amp, it appears to be an inrush thermistor, so I guess whatever is short, must be south of that ...   Arfa             Hey guess what? Today I received a Crown XLS 602. (a baby by comparison) And guess what? The mains Transformer is open circuit.   This TX is marked "NRE Electronics Manufacturing Co Ltd. 08/2006"   Dunno if that makes it from the same source or not.       Cheers,     Gareth.

"Arfa Daily" <arfa.daily@ntlworld.com>: Aug 12 06:25PM +0100 "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:I4Lyx.120054$G13.70446@fx14.am4...   > Cheers,   > Gareth.   Certainly the same as Phil's one. I don't know who made the one in my '5000. There's nothing I can immediately see to identify it, but there may be something when it's out - if of course the owner goes ahead. It's going to need a pair of spanners big enough to take off tractor wheel nuts ... :-)   Arfa

"Gareth Magennis" <sound.service@btconnect.com>: Aug 12 06:28PM +0100 "Arfa Daily" wrote in message news:dkLyx.116774$tz.81613@fx02.am4...       "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:I4Lyx.120054$G13.70446@fx14.am4...   > Cheers,   > Gareth.   Certainly the same as Phil's one. I don't know who made the one in my '5000. There's nothing I can immediately see to identify it, but there may be something when it's out - if of course the owner goes ahead. It's going to need a pair of spanners big enough to take off tractor wheel nuts ... :-)   Arfa           The customer said it had been in storage the past 2 years. He fired it up today and it blew all the main fuses in his gaff. So sounds like it may have been short like yours and Phil's, then blew open.       Gareth.

"Gareth Magennis" <sound.service@btconnect.com>: Aug 12 09:37PM +0100 "Gareth Magennis" wrote in message news:qnLyx.273309$121.130462@fx19.am4...       "Arfa Daily" wrote in message news:dkLyx.116774$tz.81613@fx02.am4...       "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:I4Lyx.120054$G13.70446@fx14.am4...   > Cheers,   > Gareth.   Certainly the same as Phil's one. I don't know who made the one in my '5000. There's nothing I can immediately see to identify it, but there may be something when it's out - if of course the owner goes ahead. It's going to need a pair of spanners big enough to take off tractor wheel nuts ... :-)   Arfa           The customer said it had been in storage the past 2 years. He fired it up today and it blew all the main fuses in his gaff. So sounds like it may have been short like yours and Phil's, then blew open.       Gareth.           Er, except customers tend to lie a lot.   He may have tried to boot several times with various size fuses/paper clips etc.     Gareth.

"Arfa Daily" <arfa.daily@ntlworld.com>: Aug 13 01:58AM +0100 > He may have tried to boot several times with various size fuses/paper > clips etc.   > Gareth.   That would be my feeling. It would seem that when these trannies fail on the primary, they do it in style. The one in this 5000 is *so* short-circuit, it blew the fuse in the mains lead plugtop, the fuse in the bench input lead where it plugs into the heavy duty extension cable, and the fuse in the extension plugtop. Oh yes, and it popped the breaker in the consumer unit as well. I've had a few mains shorts over the years, but I can't remember one that has ever taken out three mains fuses in series, *and* the breaker. Just goes to show how slow the breaker is though, compared to the cartridge fuses in the plugs. But then I suppose it is over twice their rating, at 30 amps ...   Arfa

Phil Allison <pallison49@gmail.com>: Aug 12 09:30PM -0700 Gareth Magennis wrote:   > This TX is marked "NRE Electronics Manufacturing Co Ltd. > 08/2006"   > Dunno if that makes it from the same source or not.     ** It's exactly the same as the one I described as "rough as guts".       ... Phil

Phil Allison <pallison49@gmail.com>: Aug 12 09:51PM -0700 Gareth Magennis wrote:     > The customer said it had been in storage the past 2 years. He fired it up > today and it blew all the main fuses in his gaff. > So sounds like it may have been short like yours and Phil's, then blew open.   ** Hmmm - that should not happen.   However, if the amp worked even for a few seconds, the chunky relay next to the PTC closes and bridges it out. If the primary shorted out after that, it is possible the relay contacts became instantly welded closed.   The fault current could then trip the breaker in the 30A ring mains and easily blow any fuse fitted inside power plug.   A subsequent attempt to switch on the amp would result another huge surge and maybe make a track on the PSU board vaporise.   BTW:   IIRC, the secondary voltages and currents are printed on the side of the tranny. The tranny is about 800VA and it ought to be possible to have one made that is close to the same size and ratings for an acceptable cost.     ... Phil

sound.service@btconnect.com: Aug 13 05:49AM -0700 On Thursday, August 13, 2015 at 5:51:55 AM UTC+1, Phil Allison wrote:   > IIRC, the secondary voltages and currents are printed on the side of the tranny. The tranny is about 800VA and it ought to be possible to have one made that is close to the same size and ratings for an acceptable cost.   > ... Phil       They are. 74/0/74 and 18.3/0/18.3     Cheers,     Gareth.

Phil Allison <pallison49@gmail.com>: Aug 13 06:02AM -0700 > They are.   > 74/0/74 and 18.3/0/18.3   ** The 74-0-74 winding is rated at about 6 amps.   The 18.3-0-18.3 needs only 0.6 amp but is in fact tapped off the main winding.     ... Phil

"Arfa Daily" <arfa.daily@ntlworld.com>: Aug 10 05:33PM +0100 "Phil Allison" <pallison49@gmail.com> wrote in message news:fa32623b-8488-42c9-93ae-e4db0ae15e34@googlegroups.com...   > ... Phil   Today, having pulled all of the cabling out of the way, It was possible to see where the secondary wires spaded onto the lower PCB, and there was just enough room between the board stack and the cabinet side to mark them, and pull them with a pair of long-nose pliers. I then shorted the blown-out thermistor, and hooked up the variac again. Same as before. 20 volts of input, and the variac is grunting fit to bust, so it does look like the transformer primary is shorted turns, as that's now the only thing connected. So now a case of seeing if we can get the tranny and inrush thermistor, and more to the point, at what price ...   Arfa

Jeff Liebermann <jeffl@cruzio.com>: Aug 10 04:18PM -0700 >"They all do that"   The cooling system is not always designed as badly as the HP. Here's a Dell Inspiron 1525 cooling system: <http://802.11junk.com/jeffl/pics/repair/Dell%20Inspiron%201525/> Note that the weird shaped bottom hatch give me access to the fan after I remove the heat pipe. I would have liked to also have access to the fan intake, but it was easy enough to clean with a brush and pipe cleaner.     -- 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>: Aug 10 08:12AM -0700 >>a bee keepers smoker for clues: >><http://www.dave-cushman.net/bee/smofuel.html>   >How about using incense?   I haven't tried incense but I suspect it will not produce enough visible smoke.   Also, since the machine under test is usually borrowed, methinks the owner might not appreciate having his machine internally coated with a layer of smelly oil. I had that problem when I used some of the pine kindling I save for starting my wood burning stove. The sap (creosote) was carried along with the smoke and made the case reek like a pine tree. Fortunately, most of it condensed near the air intake, so all I had to do was solvent wash the grill work and Dell's one big case fan. What you want is a finely divided ash, not a smelly or oily glue.   Sigh. I guess they don't teach combustion, bomb making, and arson in the skools any more. We had "burn baby burn" while I was in college, but I guess later generations were too busy burning incense, getting stoned, and fighting smog to bother learning about rapid oxidation. Very sad and depressing commentary on the deteriorating quality of education methinks.   Hints: Don't get the mix too hot, humidity has a big effect, figure out which way the wind is blowing first, and don't inhale the smoke. Too much oxidizer will cause the steel case to rust or the mix to act like flash powder. Try not to Learn by Destroying your computah. <http://chemistry.about.com/od/chemistryhowtoguide/a/coloredsmoke.htm> <http://xtrem-experiments.com/pyro-compositions/colored-smoke.html>   -- 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>: Aug 10 01:56PM -0700 >H-P designed computers for office conditions.   I know. My office has a condition.   >Blaming H-P form our slovenliness is un-called for ...   The first step to solving a problem is to blame someone. If I can't blame HP, would you consider being the designated culprit?   >Walmart sells round white grippy pads with AAA adhesive once >the grease goes off your laptop with methyl chloride raising >vents just so for better cooling and no slip on slide surfaces...   I use a door matt with lumps and bumps to improve the air flow under the laptop. Everything I've tried to stick to the bottom of my laptop usually falls off when the car gets too hot and the glue softens.   The grease remover is usually just alcohol, not methylene chloride or dichloromethane (furniture stripper).   >I lost the 1705E from G's out of the Turbo.   That would be a Dell Inspiron e1705. <http://www.dell.com/content/topics/topic.aspx/global/products/inspn/topics/en/inspn_e1705_sp_overview?c=us> Slow CPU <2GHz. Limited to only 2GB of RAM. No HDMI port. Only XP drivers available. Nice 1600x1200 optional display but with limited viewing angle. Did you actually pay money for this thing?   The literature says it's for a "road warrior". Are you a road warrior or do you prefer to ride in the dirt and mud?   -- 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

JW <none@dev.null>: Aug 10 08:00AM -0400 On Sat, 08 Aug 2015 20:11:50 -0700 Jeff Liebermann <jeffl@cruzio.com> >smoke, but the flames went out too quickly. Read about what goes into >a bee keepers smoker for clues: ><http://www.dave-cushman.net/bee/smofuel.html>   How about using incense?

N_Cook <diverse@tcp.co.uk>: Aug 10 10:12AM +0100 Hitachi CP X327, 3xLCD & discharge lamp, unusually the full component level sm is out there. As the lamp repeatedly strikes across giving short bursts of preliminary greenish light, the 5KV or so striking supply must work and also I assume some voltage from the main sustain, high power lamp ps, until the unit goes into protect mode. Initially I intend jury-rigging across (with added insulation) another known good lamp to see if a lamp problem. The lamp looks visibly fine, no cracks/crazes in the glass and no blacking in the active bulb area. Monitoring the mains supply current, usual surge for the low power ps coming on but only a hint of a surge for the high power ps coming on. I've previously had a projector where all that was wrong was the mains switch had arc-pitted contacts and could not supply the current for the lamp ps and so similar mains current symptom. I'll check that and check the internal cabling connectors, but what else to check, assuming it is a ps issue after the fudged lamp test also fails to light.

N_Cook <diverse@tcp.co.uk>: Aug 10 12:35PM +0100 Same weak green flashes on another bulb, so dig out the HV attenuator to see if there is 100V or so on the lamp supply at anytime, other than the 5KV trigger pulses

MJC <gravity@mjcoon.plus.com>: Aug 10 10:33AM +0100 In article <d42bdaa5-2856-4d16-a0d4-ef46574afb4b@googlegroups.com>, jurb6006@gmail.com says...   > >But now, the volume control may not be a suitable marker, the control may > >not be attenuating the audio signal, but varying a DC voltage to control a > >stage that is controlling volume."   > Or a rotary encoder going to the microprocessor.   I rather like my old JVC hi-fi in which the remote control (which unfortunately was stolen!) causes a motor to turn a nice large volume control knob, on which a flashing LED shows what setting it has reached. Much better than a digital display!   I have only recently given up using my Nikko TRM 40LA amplifier which I bought second hand from an ex-pat colleague on a business trip to NY City in the early 1970s. Although it was fairly heavy (with of course a large power transformer) it came back to the UK embedded in my dirty laundry in my suitcase. Since the instruction booklet included a schematic I tweaked some circuits as I saw fit...   Mike.

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