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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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