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"pfjw@aol.com" <pfjw@aol.com>: Nov 11 10:55AM -0800 On Friday, November 11, 2016 at 10:15:18 AM UTC-5, Mark Storkamp wrote:   > let's see, how many things can go wrong here.   https://www.dropbox.com/s/huq5ehstsoe0cbo/maglev%20wild%20speculation.docx?dl=0   This is my wildly speculative speculation on how this system could work and be effective. Some points:   a) Neodymium magnets are wildly powerful. And can be shaped more efficiently than many other materials. b) By offsetting the suspension rings as shown, the forces centering and keeping the platter level would be very strong - certainly stronger than most suspension springs for that matter. c) And there would be negligible elastic forces - that is, no wobble or bounce. That window fan would not have a chance. Damping, similarly. d) The wow and flutter issue, though very real, would be pretty much eliminated by the mass of the platter (considerable) coupled with the very negligible mass of the drive motor. e) As the platter is essentially frictionless, it would not take much to keep it running once started. I would anticipate a few seconds of start-up, but after that, gyroscopic effects would contribute to leveling and to speed control. The couple of grams on the stylus, again, would not have a chance. f) The soft shut-down is already addressed. There is an on-board soft shut-down capacity that will raise the posts and lift the stylus. g) As to magnetic fields - consider that both the suspension field and the drive fields are static relative to each other. Meaning that there will be very little generated by way of stray fields, and that the platter, if properly designed, will be enough to shield the cartridge. Considering what goes on inside my HK/Rabco without ill effect, or my Revox B295, this would be low on my worry-scale.   Again, this is a neat trick, not something I intend to purchase. But a neat trick that appears to be both possible and reasonable to execute.   Peter Wieck Melrose Park, PA

Mark Storkamp <mstorkamp@yahoo.com>: Nov 11 03:59PM -0600 In article <b3dbfbea-5345-4abb-84d2-e42d3be3831d@googlegroups.com>, > trick that appears to be both possible and reasonable to execute.   > Peter Wieck > Melrose Park, PA   Still seems like it would be a lot easier to use direct drive and air bearings. But since it's already been done, there wouldn't be as much money in it.

ohger1s@gmail.com: Nov 11 02:58PM -0800 On Thursday, November 10, 2016 at 2:16:10 PM UTC-5, micky wrote: > hard-earned money?   > http://www.avsforum.com/mag-lev-turntable/   > Brooklyn-Baltimore Guy       Seems like a solution in search of a problem. In a world filled with people who now listen to MP3s or other forms of compression I wonder how many folks in the world would want this even if it does all it promises.   And, I'm willing to bet that in a double blind test with even quality tables at the lower end of the spectrum, this toy's superiority would not be discernible, even if "audiophiles" do avoid double blind tests.

ohger1s@gmail.com: Nov 11 03:07PM -0800 > > Brooklyn-Baltimore Guy   > Seems like a solution in search of a problem. In a world filled with people who now listen to MP3s or other forms of compression I wonder how many folks in the world would want this even if it does all it promises.   > And, I'm willing to bet that in a double blind test with even quality tables at the lower end of the spectrum, this toy's superiority would not be discernible, even if "audiophiles" do avoid double blind tests.   Just watched this video:   https://www.youtube.com/watch?v=Ky0D00iyHAA   There is a LOT of platter movement beyond the rotating moments going on here. Check 0:42

MJC <gravity@mjcoon.plus.com>: Nov 11 11:25PM In article <91019702-84a9-4ff2-9e60-9673226223e2@googlegroups.com>, ohger1s@gmail.com says...   > And, I'm willing to bet that in a double blind test with even quality tables at the lower end of the spectrum, this toy's superiority would not be discernible, even if "audiophiles" do avoid double blind tests.   Just been watching on TV a single-blind test of three turntables costing approx order of magnitude amounts apart. The two listeners claimed to put then in order of merit per cost!   Mike.

whit3rd <whit3rd@gmail.com>: Nov 11 04:09PM -0800 On Thursday, November 10, 2016 at 12:29:19 PM UTC-8, Jon Elson wrote:   > Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have > strong doubts it can be stable at that height. Also, the thing must have an > insanely strong external magnetic field.   Rogers Ritter published on a low-rumble magnetic suspension audio turntable back in the seventies; he was using magnetic attraction, and some active feedback, and was more interested in physics (gravity research) than audio. If these folk have a patent, that's not what they're doing.   What puzzles me, is how there's enough reliable torque on the rotor. > Now, the only way I know one-sided levitation at low speeds can work is with > something that TOTALLY excludes flux lines, ie. a superconductor.   To levitate a light platter at low speeds, you could get use fixed magnets and a 2-d conductor (pyrolitic graphite, doped, is light and has conductivity better than copper). Levitation distances of a few millimeters would work, after spin-up. No torque, though, if that's the only trick used.   > So, the only way this thing could work is with a spinning Halbach array .. or > massive high-field magnets underneath and a room temperature superconductor   Third possibility fixed magnets, spinning conductor. And smaller gap than the pic shows.   Lots of info on the magnet-bearing subject:   <https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19920018478.pdf>

Jeff Liebermann <jeffl@cruzio.com>: Nov 11 05:42PM -0800 On Thu, 10 Nov 2016 14:16:07 -0500, micky <NONONOmisc07@bigfoot.com> wrote:   >hard-earned money? >http://www.avsforum.com/mag-lev-turntable/ >Brooklyn-Baltimore Guy   I wonder how it will work on my old warped vinyl records?   Keeping it centered to within half a track width or less might be difficult with the needle applying a side force which is probably not consistent across the tone arm swing. I expect to see a levitated tone arm in the next version.   Fighting gravity seems to be the current obsession in turntables: <https://www.gramovox.com/pages/floating-record>     -- 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

Jon Elson <elson@pico-systems.com>: Nov 11 09:38PM -0600 > https://www.youtube.com/watch?v=Ky0D00iyHAA   > There is a LOT of platter movement beyond the rotating moments going on > here. Check 0:42 Yup, about a 2 Hz oscillation when he plinked the platter, and it seems to have REALLY poor damping! It just kept wobbling.   Jon

Phil Allison <pallison49@gmail.com>: Nov 11 08:51PM -0800 Jon Elson wrote: > although with strong tapered AC fields, it is possible to repel a conductor. > I've seen this done with a big 3-phase AC motor stator and an aluminum > platter. But, the motor draws insane current and the platter gets hot fast.   ** OK, my two cents worth:   The specs say the power consumption is only 12 watts - so static lift must be achieved with permanent magnets.   There are no claims made for W&F so it must be poor, mostly due to imperfect centring of the LP. There are no claims that it is a genuine, hi-fi turntable.   The platter wobbles and bounces for ages when disturbed, hence the use of support pegs when not running.   The lack of important details and the OTT marketing videos makes it all smell very badly of SCAM.       .... Phil

micky <NONONOmisc07@bigfoot.com>: Nov 12 12:30AM -0500 In sci.electronics.repair, on Thu, 10 Nov 2016 14:32:14 -0600, Jon Elson   >> http://www.avsforum.com/mag-lev-turntable/   >> Brooklyn-Baltimore Guy >Oh, boy! Did you see how HIGH they levitate the platter? Geez, I have   Good point. Even if they can raise it that high, it seems it would both conserve assets and increase reliability to just lift it a quarter inch. Wouldn't that give all the alleged advantages and no added disadvantages? So that makes it look like a fraud.   Parts of the video looked to me someone like it was an animation.   >strong doubts it can be stable at that height. Also, the thing must have an >insanely strong external magnetic field. ....   >Brooklyn? As in Brooklyn bridge? Yup, sounds pretty appropriate, I'm very   I only gave my cities because I sent copies of the first post to some friends, but I keep using different email addresses in different places and one said he couldn't tell if it was from me or someone he didn't know.

isw <isw@witzend.com>: Nov 11 11:14PM -0800 In article <MPG.328fc9e35db38c9b37@news.plus.net>, > go for it. Impress your friends and enemies as well.   > I'm sure a vertical turntable was marketed decades ago. I don't remember > the supposed advantage, though...   Fit better in tiny Japanese apartments.   Isaac

Phil Allison <pallison49@gmail.com>: Nov 11 11:34PM -0800 micky wrote:     > Parts of the video looked to me someone like it was an animation.   ** I had the same feeling, close-ups of the patter and PU looked like CGI.   The Mag-Lev company is based in Slovenia - so likely immune from consumer fraud litigation and operating only over the net is such a warning.   If it is somehow for real, the dudes have gone to considerable trouble to make it look FAKE.       .... Phil

micky <NONONOmisc07@bigfoot.com>: Nov 12 03:53AM -0500 In sci.electronics.repair, on Thu, 10 Nov 2016 15:24:17 -0800 (PST), >t is not a really good idea. It is one hell of a novelty, as this is and if= > you got the money honey, go for it. Impress your friends and enemies as we= >ll.   I'm still trying to get past the vertical CD holder on some computers.   My brother had a friend who told him about a "good investment". that sounded like a really high-tech company. But its webpage was small, only with animations and no photos, and their list of clients was almost all prospects who hadn't signed yet.   I actually got their company address and looked at the satellite pictures. The office was small in a little strip mall, and the work location only had room for 3 trucks. But still, perhaps it was a business that could grow a lot, if they could raise capital, but after a lot of reading, it seemed all they do is dispose of the waste water from carwashes. Sure there's a market for that, becuase of laws against runoff, but it's not so hightech and there must be plenty competition.   My brother's friend had actually driven a couple hundred miles to look at the plant and he invested. I wonder if he saw in person more than I could see on the computer, or if they just took him some place and showed him something that wasn't even theirs. At the time I posted on another ng and someone knew of just such a scam. IIRC they went on weekends when the real employees were not there, put up a sign before the mark arrived and and took it down as soon as he left.   A year later, I didn't get a new list of clients but the webpage was the very same. It's too touchy a subject to ask the friend how he made out with his investment.

micky <NONONOmisc07@bigfoot.com>: Nov 12 03:54AM -0500 In sci.electronics.repair, on Thu, 10 Nov 2016 15:33:24 -0800, John   >Vertical record players have been around since at least the 1940s... >Seeburg jukeboxes all used vertical storage and play of both 78s (1940s) >and 45s right to the end - early 1990s.   Good point.

micky <NONONOmisc07@bigfoot.com>: Nov 12 03:58AM -0500 In sci.electronics.repair, on Fri, 11 Nov 2016 09:15:15 -0600, Mark   >And that's without putting much thought into it. But it seems they've >already exceeded their goal and have more than $400,000.   Oh yeah. So it should be on the market soon. :-)

micky <NONONOmisc07@bigfoot.com>: Nov 12 05:01AM -0500 In sci.electronics.repair, on Fri, 11 Nov 2016 09:15:15 -0600, Mark   >4) better have a UPS. You don't want that platter crashing down when the >power goes out.   From the kickstarter page:   Accidents happen, and we know that sometimes you may encounter a power outage, so we've designed the turntable with a UPS system. This solution stores enough power to safely lift the tonearm, stop the record, and return the platter feet to resting position. This way the turntable and your record remain in perfect condition even when the unexpected happens.

micky <NONONOmisc07@bigfoot.com>: Nov 12 05:08AM -0500 In sci.electronics.repair, on Fri, 11 Nov 2016 17:42:24 -0800, Jeff >>http://www.avsforum.com/mag-lev-turntable/ >>Brooklyn-Baltimore Guy   >I wonder how it will work on my old warped vinyl records?   I've got a 45 I must have left in the sun, and it has waves literally an inch and a half high, circling around the center. The needle can't come within an inch of the troughs.   I call it a rock and roll record.   >difficult with the needle applying a side force which is probably not >consistent across the tone arm swing. I expect to see a levitated >tone arm in the next version.   And maybe a levitated easy chair and ottoman!

Bruce Esquibel <bje@ripco.com>: Nov 12 01:05PM > I'm sure a vertical turntable was marketed decades ago. I don't remember > the supposed advantage, though...   I still own and use one, a Mitsubishi LT-5V.   The main advantage to it, it's practically immune to rumble via outside sources. Within reason, stick it on a wobbly table with a loose floor, jump up and down while it's playing and, nothing.   It's not the greatest turntable ever built for other things (besides looks) but it is good at that one thing. Up and down vibrations just don't bother it.   -bruce bje@ripco.com

MJC <gravity@mjcoon.plus.com>: Nov 12 01:56PM In article <o0743c$hh3$1@remote5bge0.ripco.com>, bje@ripco.com says...   > I still own and use one, a Mitsubishi LT-5V.   I googled that and saw a Technics one, too. They both say they are "linear tracking", so I guess it must be a bit like a CD/DVD mechanism.   Mike.

Adrian Caspersz <email@here.invalid>: Nov 12 12:07PM > WHERE CAN I FIND THESE SCHEMATICS ON LINE ? > I NEED ON AS WELL FOR A AWR1-1W   > the problem with MY unit IS IT HUMMS LOUDLY WHEN TURNED ON ? caps I GUESS ?   Are you DONALD TRUMP?   -- Adrian C

"Mr. Man-wai Chang" <toylet.toylet@gmail.com>: Nov 12 08:11PM +0800 On 12/11/2016 8:07 PM, Adrian Caspersz wrote:   > Are you DONALD TRUMP?   Are you DONALD TRUMP, Maseter? :)

"Michael A. Terrell" <mike.terrell@earthlink.net>: Nov 12 06:50AM -0500 >> They apparently think well enough not to vote for Hillary.   > Time will tell.   > Most of the time cattle, sheep and even chickens will march right up the ramp into the slaughterhouse without any hesitation at all, even with the full visual of their fellow herd companions being shocked, beheaded or otherwise abused directly in front of them. That is the sort of "think well enough of" that we are discussing.     You do know that Bengazi was an attempt for Hillary and Obama to recover weapons she illegally sold to our enemies? The same ones who behead people. That the so called anti trump protests are funded by the Nazi conspirator, George Soros?   It is the sheep who sell their soul for a free cell phone and section eight housing.     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

"Michael A. Terrell" <mike.terrell@earthlink.net>: Nov 12 06:32AM -0500 Pat wrote: >>> wired for cable. Damage to poles can knock connectors partially loose, >>> allowing a LOT of signal to flow onto the outer sheath. Could be a signal >>> right on the same frequency as Chan 4.   The connectors on the trunklines and feeders are 5/8-27 thread, and are quite strong. The housings have a pressed in stainless steel insert so the threads don't strip out easily. Also, the 60VAC @30A, modified square wave that powers the trunk and bridging amplifiers is carried on the rigid coax. If it is loose enough t radiate, it will have a high enough resistance to prevent the amplifier from working. The RayChem heatshrink ceramic connectors we used in the mid '80s were so strong that the outer aluminum tubing would break, instead of the connector to shield connection.     > channel 4 signal. That is certainly possible even if different > modulation schemes are used. (And by channel 4, we mean virtual 4 - > RF 30).     Different modulation systems would not mesh, and cause a weak signal from phase reversal. Download the Blonder Tongue Design Guide, and read it. CATV systems rarely carried A TV station on the same channel that it was transmitted on. For instance, United Video in Cincinnati, had custom labels for their converters. Instead of Ch 2 to 37, they were labeled 1 to 36. So, Channel 12 was actually on Ch 13 to prevent problems with direct pickup. The actual Ch. 12 carried one of our in house generated channels.     <http://www.blondertongue.com/UserFiles/file/documents/2012%20BRG%20FINAL_lo-res.pdf>     -- Never piss off an Engineer!   They don't get mad.   They don't get even.   They go for over unity! ;-)

N_Cook <diverse@tcp.co.uk>: Nov 12 11:15AM I have to decide how much time to spend on this Vocalist live3, DSP harmoniser, indoors but ended up directly underneath a rainfall gully leak of the house roof. Instead of opening up and hairdrying, owner just put on a room radiator overnight before powering up, via external 9V ac wall wart. I have to decide how much time to spend on this. If there is no corrossion product, mainly white stuff like battery corrossion product or "tide-mark", anywhere in the DSP area does that mean water did not get there? No front panel LEDs or sw responses, main 7805 v reg is ok and one SMD LED on the pcb lit. No fuses/CPs found. I can find no schematic for this. There was still water inside this kit when I got it. Obvious corrossion product lightly brushed off easily, from around pins of stuff in the internal ps area, would it be tin salts, tin carbonate or some such ? Just some staining of the pins , no obvious failed copper tracks and very little green corrossion product. I've not determined yet whether multilayer pcb.

akash.ganguly03@gmail.com: Nov 11 02:57PM -0800 I was able to fix my Vantage MDS8RW101 module by replacing the fuse in the module.   * Located the module which had the Fuse LED light OFF. The LEDs are one the top of the module. The Fuse LEDs are 2nd from left and the other one is 2nd from right.   * Removed module by unclipping the clips on the side of the module. - First tried to remove the vents by unscrewing the vents. Don't make the same mistake :)   * Found the fuse and replaced it with the spare.   The following document was helpful: http://design.vantagecontrols.com/lib/docs/Dimming%20Module%20MDS%20Series_install.pdf     On Wednesday, September 23, 2015 at 1:15:18 PM UTC-7, UkiwiS wrote:

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