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John Robertson <spam@flippers.com>: Apr 14 09:46AM -0700 On 2020/04/14 7:46 a.m., Tim R wrote:   > In my case putting the hard drive in an enclosure let me recover the data to another PC. The sectors with the operating system were trashed but I got her data back. I bought a new hard drive, with some effort we got an operating system loaded, and I transferred her data back.   > In your case buying a new SSD is easy. I doubt you will recover any data given your symptoms. So you still need to deal with the operating system replacement. With Win 10 I don't know how hard that is - with my old system I couldn't get a replacement OS from the manufacture because the retailer had loaded the systems. I had a friend with an XP image that worked, and eventually I converted to Linux.   > The lesson here is when you buy a laptop make a recovery disk, USB, or whatever it reads BEFORE you start using it. Eventually they all die.   Has the OP contacted HP? Their service should cover this kind of failure...   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Rob <nomail@example.com>: Apr 15 07:47AM >> The lesson here is when you buy a laptop make a recovery disk, USB, or whatever it reads BEFORE you start using it. Eventually they all die.   > Has the OP contacted HP? Their service should cover this kind of failure...   > John :-#)#   Probably limited to replacing the SSD module, when you are lucky filling it with a factory-standard Windows image. And returning it, mentioning "now please restore your backup". Often not really what customers are hoping for.

Tim R <timothy42b@aol.com>: Apr 15 05:22AM -0700 On Tuesday, April 14, 2020 at 12:46:49 PM UTC-4, John Robertson wrote:   > Has the OP contacted HP? Their service should cover this kind of failure...   > John :-#)#   Should, but it's 3 years old, out of warranty I'd think.

Mike S <mscir@yahoo.com>: Apr 14 09:07PM -0700 I have Skullcandy Crusher headphones and the hinge plastic broke. It's a really common problem with them. I don't need a hinge, I'd like to epoxy the hinge joint in the fully open position as it would be when being worn. I tried using 2 part epoxy to hold it together, but it wasn't plastic rated epoxy and it held perfectly for about 4 minutes, it was easy to pry off of the plastic and it was clear it didn't adhere well at all. I remember making plastic model cars and planes as a kid, the glue seemed like it melted the plastic pieces into one another for a really good joint, like a weld in metal. I don't know what grade the plastic they used for the joints is and I don't know how to find that information. Is there an all purpose adhesive or epoxy that I can use to make one big solid mass of plastic? Or do I pretty much have to try the various adhesives used for different grades of plastic?   This amazon ad says   Loctite Super Glue Plastics Bonding System with Activator 2-Gram (681925)   Bonds plastics such as Plexiglas, polycarbonate, polystyrene, PVC, polyethylene, polypropylene and polytetrafluoroethylene (PTFE)/Teflon. Plus rubber, leather, cork, paper, cardboard, wood, chipboard, fabric, metal and ceramic.   https://www.amazon.com/Loctite-Plastics-Bonding-Activator-681925/dp/B000Y3LHXW     Loctite sells 2 different adhesives for these two different types of plastic   The easiest way to identify a plastic type is by its label, commonly a recycling symbol. Plastics marked with a 6 or "PS" are polystyrenes. These are used for simple items like disposable cutlery, plastic bowls, or fashion bags. For these, the best glue is a poly cement such as Loctite Plastic Bonder.   Other types of plastic are used for tougher industrial or construction uses, such as drainpipes. Special plastics are even used for medical applications and bulletproof vests. For gluing these plastics, try Loctite Plastics Bonding System, which creates a powerful bond with just one drop.   https://www.loctiteproducts.com/en/know-how/fix-stuff/plastic-glue.html     JB Weld PlasticWeld comes with this note:   While this product works beautifully with most varieties of plastic, please be aware that there are certain types - including polyethylene and polypropylene sheet - that it will not adhere to.   https://www.acplasticsinc.com/informationcenter/r/the-best-adhesives-for-plastics

b23sunwoodllc@gmail.com: Apr 14 10:27PM -0700 On Tuesday, April 14, 2020 at 9:07:42 PM UTC-7, Mike S wrote: > please be aware that there are certain types - including polyethylene > and polypropylene sheet - that it will not adhere to.   > https://www.acplasticsinc.com/informationcenter/r/the-best-adhesives-for-plastics   I use Weld*On products with lexan and acrylics. It is a solvent as you describe. I imagine that they have products for your plastic. https://weldon.com/   Good luck.

Jeff Liebermann <jeffl@cruzio.com>: Apr 14 11:36PM -0700 >Plus rubber, leather, cork, paper, cardboard, wood, chipboard, fabric, >metal and ceramic.   >https://www.amazon.com/Loctite-Plastics-Bonding-Activator-681925/dp/B000Y3LHXW   That's what I use for gluing problem plastics. Seems to work with all the hard plastics and some soft (flexible) plastics. It's a cyanoacrylate adhesive, with some hexane added to soften the plastic. Note that it's not very good at filling gap. With flexible plastics, it does well if the glue joint is very thin and therefore flexible. With a thicker glue line, it will crack and eventually crumble.   Another glue that I've found that works well with hard plastics is Zap-It. It's also a cyanoacrylate adhesive with some manner of solvent to soften the plastic. What I like most about it is that if I use the UV light to cure the joint, I don't need to wait until it hardens. I'll know if I have a decent joint in seconds. <https://supergluecorp.com/product/zap-it/> One catch is that it works best on transparent plastics, where the UV light can penetrate. However, if the plastic is opaque, just slop on some glue which leaks outside of the joint, harden what's visible with the UV light, and let it sit for about an hour. Even without the UV light, the cyanoacrylate adhesive will harden in less than an hour.   "ZAP ITŽ Glue" <https://www.youtube.com/watch?v=Pg1zRNQISyU>   No clue on the other stuff you mentioned as I haven't tried those.   -- 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

Andy Burns <usenet@andyburns.uk>: Apr 15 07:47AM +0100 Mike S wrote:   > Loctite sells 2 different adhesives for these two different types of > plastic   Try the 'burn test' to identify the plastic if its type isn't marked on it   <https://www.boedeker.com/Technical-Resources/Technical-Library/Plastic-Identification>   if it's a low surface energy type, there is Scotchweld DP8005, but it's not cheap

Mike S <mscir@yahoo.com>: Apr 15 01:02AM -0700 On 4/14/2020 11:47 PM, Andy Burns wrote:   > <https://www.boedeker.com/Technical-Resources/Technical-Library/Plastic-Identification>   > if it's a low surface energy type, there is Scotchweld DP8005, but it's > not cheap   Thanks very much b23sunwoodllc, Jef Liebermann, and Andy Burns,   the burn test is great, I'll make a purchase based on those results.

HW <none@no.no>: Apr 15 01:19PM +0200 >Is there an all purpose adhesive or epoxy that I can use to >make one big solid mass of plastic?   No, unfortunately there is not. Plastics is a huge group of materials with large differences in properties.   If at all possible, find out which type(s) of plastic you are dealing with. Larger plastic parts usually have mark, in a normally invisible location, that indicates plastic type.   If you can't find out, the job is merely a matter of trying different things until you run out of patience.   I do not have personal experience with the products you mention, but if it claims to be able to glue plastics such as PP and PTFE, it might be well worth a try. Those plastics, along with PA (PolyAmid / Nylon), are usually considered practically ungluable.   Your application is a high stress one, so it is possible a glue joint will not be able to last, even with a glue that works. Sometimes, a mechanical repair can be used. Some sort of bracket or clip that is screwed in place, for example.

Jeff Urban <jurb6006@gmail.com>: Apr 14 01:22PM -0700 It is not practical to use a FET. The bipolar transistor is driven by current, the FET by voltage. The drive circuit is different because of that.   To swing the output all the way to the rails with an enhancement mode FET requires voltage higher than the rails. At least I think so, because being germanium it is 99% that they are both PNP.   As such they are probably TO-3 from what you described. I that case I think you would do best with like MJ15023s. Decent gain, fairly linear and with not alot of voltage requirement for bias.   As I service vintage audio I am getting good at bias. The last unit for example does not have an adjustment, I changed a resistor value from 680 to 729 to make it come out right.   So go in with the mindset you are going to have to increase the bias VOLTAGE to get to the proper CURRENT. In some cases you only have a stack of diodes to produce the drop, in some cases you got a little transistor biased on, or almost all the way on and they use its thermal characteristics to match the outputs. Either way you probably know enough to make it drop a little more voltage. And I would venture to say that the power transformer in the unit doesn't have the balls behind it to blow MJ15023s.   To use a FET you have to give it voltage drive and that might mean adding a stage. The original drive stage is meant to use current, like the transistors.   Now there is a possibility that the outputs are transformer driven. Yup, they had split winding driver transformers for the SESAPP circuit. I you got that it is practically impossible to modify. If it was built when NPN transistors were scarce that was the way to do it. Without both polarities of bipolars it is a real bitch to design an SESAPP output circuit without a transformer. A few manufacturers did it but it was a fucking mess. Soy did it I know, and it was a fucking mess but so was half of everything they did. Yep, and I was the one who had to figure this shit out.   If you think they had it easy, try designing a power output circuit using transistors - but of only one polarity. A bitch. You have to depend on the specs of all the transistors or else it will be flooded with even order harmonic distortion.   On the other hand I think I got a set of four 2N5436s. Those are almost unblowable at lower voltages. Real germanium and TO-3 but with 60 mil pis. Good to 60 amps. If you blow those you is a bad mofo.   Just use the damn 15023s. they will do it and all you have to do is mess with the bias, the rest will all work.   Don't make problems for yourself. We have plenty of people to do that.

John Robertson <spam@flippers.com>: Apr 14 01:47PM -0700 On 2020/04/14 1:22 p.m., Jeff Urban wrote:   > On the other hand I think I got a set of four 2N5436s. Those are almost unblowable at lower voltages. Real germanium and TO-3 but with 60 mil pis. Good to 60 amps. If you blow those you is a bad mofo.   > Just use the damn 15023s. they will do it and all you have to do is mess with the bias, the rest will all work.   > Don't make problems for yourself. We have plenty of people to do that.   Hi Jeff,   Yeah, I figured FET was not practical.   I did see one page on line where the discussion about replacing G with S was you double the size of the original G's emitter resistor. So, if it was 75R you would change that to 150R. Have you any knowledge of that?   As for the Motorola MJ15023, they sound great, and are PNP which are what I need. Vceo 200, IcContinuous 16A, 15/60hfe, 5MhZ, and 200W dissipation. That will be hard to blow up!   I may go with a second diode to aid the temp stabilization, but I am no expert on designing transistor amps, just a dedicated plodder.   Schematic here:   ftp://www.flippers.com/pdfs/Seeburg_TSA1_Amp_Schematic_Update.pdf   Thanks,   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Phil Allison <pallison49@gmail.com>: Apr 14 04:38PM -0700 John Robertson wrote:   ------------------------   > As for the Motorola MJ15023, they sound great, and are PNP which are > what I need. Vceo 200, IcContinuous 16A, 15/60hfe, 5MhZ, and 200W > dissipation. That will be hard to blow up!   ** No hard at all.   I once had boxes of dead ones lying around - mostly extracted from amplifiers like the Phase linear 400 and 700 mk2s.   Like any bi-polar, they had limited "safe area" of about 2A at 80V for 0.5 seconds and much less at higher voltages.   Plus excessive chip temp is always fatal.   The lateral Mosfets made by Hitachi that come along in the 1980s were enormously more rugged.     ..... Phil

tabbypurr@gmail.com: Apr 14 06:04PM -0700 On Tuesday, 14 April 2020 06:36:55 UTC+1, John Robertson wrote:     > Suggestions welcome!   > Thanks!   > John :-#)#   The differences between Ge & Si go further than just bias voltage. You could try it but don't get too excited, some amps simply won't fly with Si.   Russia still puts out lots of geraniums, don't know what power devices they have but I expect you'd find something usable. Prices are good. In extremis you could probably parallel a bank of small trannies with sharing resistors.   FET require much larger input voltage swings.     NT

John Robertson <spam@flippers.com>: Apr 14 06:33PM -0700 On 2020/04/14 4:38 p.m., Phil Allison wrote:   > Plus excessive chip temp is always fatal.   > The lateral Mosfets made by Hitachi that come along in the 1980s were enormously more rugged.   > ...... Phil   My amp runs at -46V and about 1.5A before the line fuse fails. So being derated to just under 50V should handle the limits you mention. If you have better suggestions I am most open to them.   My goal is to have a reliable and relatively simple upgrade that folks who wish to keep their jukeboxes mostly authentic can work with. Most of the amp is stable after new electrolytics are installed, it is just the outputs and their respective drivers that tend to fail due to, well, life...   Nothing to stop the owners from putting a modern amplifier in the machine and just ignore the original tech, we do that when asked.   Thanks!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Phil Allison <pallison49@gmail.com>: Apr 14 11:22PM -0700 John Robertson wrote: ----------------------     > > The lateral Mosfets made by Hitachi that come along in the 1980s were enormously more rugged.     > My amp runs at -46V and about 1.5A before the line fuse fails. So being > derated to just under 50V should handle the limits you mention.   ** No doubt, long as nothing goes wrong.   The gross failures I saw were caused, not inherent.   Those causes however were predictable.   1. Overheating due to lack of good fan cooling.   2. Overloading with too many speakers.   3. Gradual failure of one or more speakers leading to a low impedance load that causes chip temp to exceed limits.   4. The fact they are *free standing* amplifiers, not incorporated in a unit like a juke box, so exposed to external influences the amp maker's never dreamed of.   IF appears to you that MJ15023s will do the needed job, by all means use them.   I probably would.     .... Phil

tabbypurr@gmail.com: Apr 14 05:32PM -0700 On Monday, 13 April 2020 21:58:04 UTC+1, John Keiser wrote: > about $2. It turned out that I needed something slightly smaller for a > TEAC CD player but a razor blade and crazy glue worked well. The deck is > working well after 2 years.   3d printers can print belts using flexy filament.   There is also one last resort if all else fails. You won't like it but IME it does work for a lot of situations: regular rubber bands     NT

tabbypurr@gmail.com: Apr 14 05:29PM -0700 On Monday, 13 April 2020 02:13:34 UTC+1, Paul Hovnanian P.E. wrote: > 'monitor switch' which shorts the power supply. It is located immediately > across the magnetron primary. So, should al other interlocks and control > relays fail, this will indeed blow the fuse.   that's the plan   > applied to the transformer before it and/or the magnetron has bled off > energy. The resulting transient might be enough to shorten the life on > something.   The short only occurs if the primary interlock switches fail, no other situation. At which point no-one cares what it does to equipment life expectancy.     NT

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