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micky <NONONOmisc07@bigfoot.com>: Nov 10 02:16PM -0500 So is this for real, or a kickstarter designed to cheat me out of my hard-earned money?   http://www.avsforum.com/mag-lev-turntable/   Brooklyn-Baltimore Guy

"pfjw@aol.com" <pfjw@aol.com>: Nov 10 12:08PM -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   Probably For Real. Too much/many "other" sources and information out there.   Interesting idea. One does wonder how the centering and leveling functions work. I can figure out how they handle rotation. A half-price for pre-purchase is not a half-bad deal given it comes with an arm and cartridge.   Peter Wieck Melrose Park, PA

Jon Elson <jmelson@wustl.edu>: Nov 10 02:32PM -0600 micky wrote:   > hard-earned money?   > http://www.avsforum.com/mag-lev-turntable/   > Brooklyn-Baltimore Guy 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.   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.   So, the only way this thing could work is with a spinning Halbach array under the platter (which would play HELL with a magnetic phono cartridge) or massive high-field magnets underneath and a room temperature superconductor in the platter. Hmmm, can't buy that yet...   I know of no way to repel something ordinary with a steady magnetic field, 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.   Brooklyn? As in Brooklyn bridge? Yup, sounds pretty appropriate, I'm very skeptical of this one. I think it probably CAN be done, but not as a practical device, capable of operating right next to a megnetic phono cartridge.   Jon

dplatt@coop.radagast.org (Dave Platt): Nov 10 12:55PM -0800 In article <35a60b97-b7f3-402b-83da-bfce7f5407a8@googlegroups.com>,   >> Brooklyn-Baltimore Guy   >Probably For Real. Too much/many "other" sources and information out >there.   I didn't see that they cited the numbers of the patent(s) that they say they have.   >Interesting idea. One does wonder how the centering and leveling functions work. I can figure out how they handle rotation. A half-price for >pre-purchase is not a half-bad deal given it comes with an arm and cartridge.   The other trick which puzzles me, is how they keep the magnetic levitation/centering/rotation field from being picked up by the cartridge, or keeping the magnitude of the pick-up down below the noise floor of the phono preamplifier.   Years ago, some of the Grado cartridges had a bad reputation for hum when used with certain turntables - the stray fields from the AC motors were picked up by the coils in the cartridge.

MJC <gravity@mjcoon.plus.com>: Nov 10 10:47PM In article <hnh92cl1gv8dgmh2rn023fs4ltjrtivh8c@4ax.com>, NONONOmisc07 @bigfoot.com says... > hard-earned money?   > http://www.avsforum.com/mag-lev-turntable/   > Brooklyn-Baltimore Guy   Lovely ide, but I'd want to know more... Presumably the huge floating height in the "photo" is merely to make it obvious, rather than being enough to de-couple a major earthquake?   And how is the speed controlled?   Mike

jurb6006@gmail.com: Nov 10 03:24PM -0800 I see it as a novelty. It may well work and may be worth more than the sum of its parts but is it worth it ?   And forget DC coupling in the amp it drives. Levitated that high the magnetic fields needed to drive it will be substantial and be picked up by the cartridge. If it is three phase drive that works out to about 1.7 Hz, which is quite low. However if you buy such an expensive turntable you are likely to have an expensive phono preamp which may be DC coupled. So then you have to use some sort of filter to get that noise out.   I don't generally go for these pay before they are even built schemes. There is a reason that some company somewhere is not already doing this. What is half price ? Ten grand ?   That is why I am not in the one for Red Pataya, which is like an Arduino but supposedly more versatile, or something.   And I see no reason in having a turntable that is higher fidelity than the lathe on which the master record was cut.   I am not necessarily saying the people are crooks, but it is someone's pet project and they do expect to make money. There is another one out there, a vertical turntable. There are people putting money into that as well and it 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 well.

John Robertson <spam@flippers.com>: Nov 10 03:33PM -0800 > That is why I am not in the one for Red Pataya, which is like an Arduino but supposedly more versatile, or something.   > And I see no reason in having a turntable that is higher fidelity than the lathe on which the master record was cut.   > I am not necessarily saying the people are crooks, but it is someone's pet project and they do expect to make money. There is another one out there, a vertical turntable. There are people putting money into that as well and it 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 well.   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.   Sony used a vertical player for their CDs.   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."

isw <isw@witzend.com>: Nov 10 08:55PM -0800 In article <hnh92cl1gv8dgmh2rn023fs4ltjrtivh8c@4ax.com>,   > So is this for real, or a kickstarter designed to cheat me out of my > hard-earned money?   > http://www.avsforum.com/mag-lev-turntable/   The best you can do with vinyl is pretty poor; why bother?   Plus, rumble has not been a problem on "ordinary" turntables (well, decent-quality ones) for quite a while.   Isaac

Jim <noone@here.com>: Nov 11 07:21AM -0500 In article <if3ffd-95m.ln1@coop.radagast.org>, Dave Platt > levitation/centering/rotation field from being picked up by the > cartridge, or keeping the magnitude of the pick-up down below the > noise floor of the phono preamplifier.   Perhaps they use a ceramic cartridge. The sound would suffer, but it would still look pretty cool.   -- Jim

MJC <gravity@mjcoon.plus.com>: Nov 11 12:28PM In article <da39e406-8f82-48f4-88a3-c9c74f821e7a@googlegroups.com>, jurb6006@gmail.com says...   > ... There is another one out there, a vertical turntable. There are people putting money into that as well and it 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 well.   I'm sure a vertical turntable was marketed decades ago. I don't remember the supposed advantage, though...   Mike.

"pfjw@aol.com" <pfjw@aol.com>: Nov 11 05:02AM -0800 On Thursday, November 10, 2016 at 3:29:19 PM UTC-5, Jon Elson wrote:   > insanely strong external magnetic field.   > 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.   https://en.wikipedia.org/wiki/Neodymium_magnet   I have experienced these magnets directly - when we were in China, the novelty shops sold a device with what amounted to a metal puck, about the size of a hockey puck but half the thickness that could be suspended above a platform if "heads" or was very nearly impossible to remove from the platform except by sliding if "tails". Variations included a shaft that could be spun in suspension over a bed attached to the platform and another that could be twirled.   When we tried to bring it back to the US in our checked baggage, we were called to the front of the plane and informed that these things were powerful enough to interfere with aircraft navigation systems - and that we would have to either get off the aircraft and mail it, or give it up. We gave it up.   In any case, I would have no difficulty at all believing Neodymium magnets within the platter with a rotating field developed in the plinth reaching that distance. And, it would have the additional effect of 'centering' the platter as well. The platter *will* be quite heavy.   Now, one more beneficial effect of this system: The field will be, effectively, two nested donuts, and they could be rather small relative to the 12" platter given the power of the static field (in the platter) - perhaps as little/small as 6". At that size, the platter would be a shield for the cartridge both magnetically and in rF. Note that the cartridge is always *ABOVE* the field with the platter between it and that field.   Not that I am going to line up to purchase that TT. I am hooked on linear tracking arms - and unless/until that happens, it is only a neat trick, no more.   Peter Wieck Melrose Park, PA

Chuck <chuck@mydeja.net>: Nov 11 08:38AM -0600 On Fri, 11 Nov 2016 12:28:55 -0000, MJC <gravity@mjcoon.plus.com> wrote:     >I'm sure a vertical turntable was marketed decades ago. I don't remember >the supposed advantage, though...   >Mike.     One advantage was that they could be built into boomboxes and an arm could be mounted on the front and the back. (No need to flip the record) I remember when they first Sharp samples showed up at Best Buy. They were monstrosities that I thought wouldn't sell and I was right.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Mark Storkamp <mstorkamp@yahoo.com>: Nov 11 09:15AM -0600 In article <hnh92cl1gv8dgmh2rn023fs4ltjrtivh8c@4ax.com>, > hard-earned money?   > http://www.avsforum.com/mag-lev-turntable/   > Brooklyn-Baltimore Guy   let's see, how many things can go wrong here.   1) the stylus has weight required for proper tracking. It will want to tilt the platter, and the torque will vary from edge to center.   2) there's friction at the stylus, making the platter want to rotate around the point of contact.   3) the base is still coupled to the platter through the magnetic field. Vibrations will still be coupled to the platter.   4) better have a UPS. You don't want that platter crashing down when the power goes out.   5) that large of a magnetic field wont interfere with the cartridge?   6) a rotating magnetic field driving the platter will introduce just as much wow and flutter as is introduced by the motor of a direct drive turntable.   7) an open window or a fan could easily blow that platter around creating even more distortion.   And that's without putting much thought into it. But it seems they've already exceeded their goal and have more than $400,000.

Jeff Liebermann <jeffl@cruzio.com>: Nov 10 09:28AM -0800 On Tue, 8 Nov 2016 13:56:36 -0800 (PST), captainvideo462009@gmail.com wrote:   >On Sunday, November 6, 2016 at 7:40:38 PM UTC-5, captainvi...@gmail.com wrote: > I tried posting something about this in the past but got no response. (...) >I wanted to include all the background information before this thread began. Lenny   I can see why you received no response. 357 lines of disorganized ranting is difficult to parse. Please get organized and save readers the effort of wading through your mess. Same as always: 1. What problem are you trying to solve? Keep it very simple. 2. What equipment do are you using? Numbers and details are good. 3. What have you done so far and what happened?   I'm busy for a few days and will hopefully do a path profile this weekend. I don't know if I can squeeze much out of the path analysis except that you might have some obstructions or Fresnel zone diffraction problems. From the plots I previously posted, the coverage of both stations look identical.   Did you do any of the substitution tests that I recommended? The best test would be just the TV, a length of RG-6/u, and a simple 1/2 wave (at 500MHz) dipole hund outside the window. No amps or splitters.   Did you run your address through TVfool.com to see what signal levels they predict?   >BTW, here are my coordinates: and although the topo maps said >different according to Google my altitude is 115 meters   Slight misunderstanding. I need the type of antenna you are using at your house, and its elevation above ground level. You can save me some trouble excavating the information from your archive by listing everything (inclusive) between the antenna and the TV receiver.   >465 Derry Rd, Chester, NH 03036, USA >Latitude: 42.930838 | Longitude: -71.281921   Thanks for using a decent (decimal degrees) format. I hate DMS.   From the FCC data, WBZ is at 42° 18' 37.00" N, 71° 14' 14.00" W but in NAD27. Converting the FCC DMS to decimal and datum into WGS84: (42.310278 N, -71.237222W) NAD27 -> (42.31025 N, 71.23669 W) WGS84. Antenna height above ground 387 meters (1270 ft). Nice little monster tower: <http://www.necrat.us/bztower.html>   Well, I have a few minutes I'll throw together a Google Earth path profile. It won't be very accurate and won't show Freznel zones, but will show any obstructions. Looks like drawing a 1270ft tower is gonna be difficult, so I guessed: <http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ-Lenny.jpg> If you have Google Earth, here's the PRELIMINARY KMZ file: <http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ%20path.kmz> Looks like you have a rather large hill directly in the path and very close to you. A 150ft or so tower at your end would be needed to clear the hill.     Incidentally, I vaguely recall a similar OTA problem where one channel was uncharacteristically low in receive signal. It turned out to be an unterminated length of coax on a coaxial splitter. Even though the splitter was suppose to have perhaps 20dB(?) of isolation between ports, the device was so badly built that I'm sure it was much less. <http://802.11junk.com/jeffl/crud/CATV-splitters.jpg> The unterminated length acted as a notch filter which just happened to land on the TV channel frequency. Replacing the spllitter and removing the coax or terminating it with 75 ohms solved the problem.   -- 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 <jmelson@wustl.edu>: Nov 10 02:40PM -0600 Jeff Liebermann wrote:     > cables. It takes quite a bit of cable leakage to produce interference > with an OTA signal, but it might be possible in weak areas and if the > OTA TV system uses a pre-amplifier.   The OP is definitly in a weak area (45 miles from stations) and IS using an aplifier just under the antenna. Anybody within a fe miles in the general direction of the broadcast antenna could be trashing his signal. Without the proper equipment (portable spectrum analyzer), it could be quite hard to find the problem.   Jon

Jeff Liebermann <jeffl@cruzio.com>: Nov 10 07:05PM -0800 On Thu, 10 Nov 2016 14:40:12 -0600, Jon Elson <jmelson@wustl.edu> wrote:   >The OP is definitly in a weak area (45 miles from stations) and IS using an >aplifier just under the antenna.   Yep, and there's another problem: <http://802.11junk.com/jeffl/coverage/KBCZ-WBZ/WBZ-Lenny.jpg> That a really rough and crude guestimate of the path, which shows a 150ft pile of dirt blocking the signal. It could be knife edge diffraction, but I don't think so. My guess(tm) is some part of his system (antenna, amp, coax, splitter, power injector, TV) is broken.   >Anybody within a few miles in the general >direction of the broadcast antenna could be trashing his signal.   Yep. I didn't check for other UHF TV stations in his area. Overload (blocking) is possible, but usually affects ALL the channels. Since I determined that the theoretical signal strength from both WBZ and KVCB are almost identical, I don't see a nearby signal trashing one signal, but not the other. The lack of complaints about other channels also points to a specific problem on UHF channel 30.   >Without >the proper equipment (portable spectrum analyzer), it could be quite hard to >find the problem.   Test equipment is always nice to have. However, I think this one can be nailed by simply substituting parts of the puzzle and comparing the effects on both WBZ and KBCZ. When something is replaced that makes the signals equal, then the problem has been found.   However, if you really want to use a portable spectrum analyzer, any of the RTL2832U SDR receiver dongles make a nifty spectrum analyzer. <http://www.rtl-sdr.com/?s=spectrum+analyzer> I run several RTL-SDR programs on my Google Nexus 7 tablet that acts something like a spectrum analyzer. <https://play.google.com/store/apps/details?id=marto.androsdr2> The basic sensitivity of the typical USB SDR dongle sucks without an RF preamp, but should be good enough to see what's arriving from the antenna mounted amplifier.   -- 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

"Paul Hovnanian P.E." <paul@hovnanian.com>: Nov 10 06:54PM -0800 Possibly a burned or dirty spot on the control potentiometer.   -- Paul Hovnanian mailto:Paul@Hovnanian.com ------------------------------------------------------------------ Ask me about my vow of silence.

tiger56usmc@gmail.com: Nov 10 06:18PM -0800 On Monday, February 16, 2009 at 6:53:00 AM UTC-5, Arfa Daily wrote: > REV01"), and I should be able to help you with a schematic copy. What is the > problem with the unit ?   > Arfa   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 ?

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