There are some thing's I'm find interesting but that I'm not going to spend my life pursuing.
The Theremin (Wiki) is an electrical musical instrument played by using one hand to control the pitch and the other to control the volume. Since both controls depend on the capacitance between the hand and instrument sensing antenna, any body movement other than the hand will be heard. So you will notice that the performer is holding very still except for the hand movements. Pamelia Kurstin plays the theremin (TED, YouTube)
Although I would like get a full size theremin, they are priced way too high for what use I'd make of it. So when a "toy" theremin showed up at http://www.thinkgeek.com I waited till they were back in stock and got one.
The theremin was originally the product of Russian government-sponsored research into proximity sensors by Lev Sergeevich Termen (Wiki).1658953 Signaling Apparatus, L.S. Theremin, Feb 14, 1928,
1661058 Method of and Apparatus for the Generation of Sounds, L.S. Theremin (M.J. Goldberg and Son, G.M.B.H Germany), Feb 28, 1928, 84/674; 84/711; 331/37; 331/40; 331/55; 331/65; 331/181; 340/384.72; 984/383
340/562; 236/74.00R; 236/DIG.11; 246/2.00R; 246/63.00R; 246/249; 307/652; 331/176; 334/6; 336/30; 336/75; 340/590; 340/592; 361/1; 361/161; 361/181; 361/282; 455/120- any movement in a room will set off the alarm2047912 Timing System, L Theremin, Jul 14, 1936, 307/2; 368/52; 968/827 - synchronous clock run on DC
Also see my Music web page.Book: Theremin: ETHER MUSIC AND ESPIONAGE by Albert Glinsky, ISBN-13: 978-0252072758
Also see my music web page for other references.
Fig 1 Kit as received
Fig 2 magazine all about Theremins (Japanese?)
Runs on 3 AA batteries or an external wall wart.
The jar has frosted glass and as the LEDs inside dim and brighten it appears that there's movement.
From a distance it looks like a real butterfly when near a plant. Can add a AA battery, but it's not required. Not sure why you'd want to use one.
The plastic stakes are very fragile, i.e. they will break if you try to force them into the ground. You need to have a hole first then insert the stake.
A Zen Pendulum. A magnetic ball generates an electric current when it passes over a coil that triggers the discharge of a capacitor giving it a small kick to keep it going.
Powered by a small solar cell or by a mini USB jack. The black acrylic plastic has been laser cut, a neat idea.
The solar cell is an assembly made by Solarbotics who made this kit. It has a printed circuit board on the back intended for one of their other kits.
The other kits use one of the MN1381 voltage triggers (MSE solar cell combo), like the MSE2 Powerful bundle kit. The solar cell charges a big capacitor and when the cap voltage reaches the trigger point the 1381 grounds a terminal transferring the storage cap power to the load, which can be a small motor.
This works using the idea from an old patent "Novelty Electric Motor" from 1974, see Joule Thief web page and scroll down for other examples.
There are a couple of errors in the instructions.
Step 8 - use the 1/2" screws, not the 1/4".
Step 10 - save the left over double sided tape, it will be used to stick the solar cell to it's mount.
By turning off the switch and letting the ball come to a stop as pictured in the photo below a "+" mark can be made on the top.
Now, after moving the "+" mark 90 so it's facing forward the switch can be turned on and the ball given a slight nudge.
After running for a number of cycles and switch is turned off.
The "+" mark is either at or near the top.
Note: This electrical circuit has a lot in common with the Joule Thief.
An early version of this that used classical pendulum with a magnet on the tip is in Chapter 11 of the book: Junkbots, Bugbots & Bots on WHeels: Building Simple Robots with BEAM Technology by Hrynkiw and Tilden. This book has a neat idea they call the Miller Solar Engine that uses a microcontroller voltage dropout detector IC to allow a solar cell to charge a capacitor that may have application to the Joule Thief idea of recovering energy.
If the ball is left on the rails and the Sun goes down the ball ends up in the center as pictured above. The next day when there's light, but not direct Sun the ball and coil act like a loudspeaker and makes a faint beep that can take some time to track down. This unit is NOT self starting, so even when in direct Sun the ball will not start moving, but just make the faint beep.
It does turn from room lighting. So far have not got it under overhead sun.
Maybe in half a year (Now December 2018 so Sun is low in the sky).
A sphere, like a map of Earth, spins inside a clear plastic sphere for ever. Solar powered, so needs a lot of light to spin.
4.5" Blue with Relief Map on order 2018 December 1.
6853283 Frictionless self-powered moving display, William W. French, 1999-10-18 - Original method
6937125 Self rotating display spherical device, William W. French, 1999-10-18 -alternate methods
Bill French YouTube:
Mova Origins, Mova Globe origins and operation
Mova Globe : Internal Mechanism Revealed by Cutting Open -
Extant (IMDB): Black star map version on same base as mine appears on the desk of Sam Barton (Camryn Manheim), Episodes 1, 6,
This is the 8" size with a AC line power supply. There are larger and smaller sizes and some of the smaller ones run from a battery.
This still photo does not capture the motion or the effect when a hand is placed on the globe.
Here is a movie showing the motion: https://youtu.be/rKxu1DK-WZQ
The Wiki page shows a Tesla patent but Bill Parker is the inventor of this device.
454622 System Of Electric Lighting, N. Tesla, 1891-06-23 - >= 15 kHz & >=29kV AC drive
514170 Incandescent electric light, N. Tesla, 1894-02-06 - insulates the wire inside the globe, only the ball is exposed
The Parker patents are all for a hemispherical dome, but the actual product is close to a spherical globe.
4963792 Self contained gas discharge device, William P. Parker, Lahive & Cockfield, 1990-10-16
4754199 Self contained gas discharge device, William P. Parker, Lahive & Cockfield, 1988-06-28
Table 1 possible gas mixtures
D322489 Decorative gas plasma light display, William P. Parker, Lahive & Cockfield, 1991-12-17
With the power off, after plugging in the power pressing the touch switch does nothing. In order to turn the unit on, the lamp must first be removed, the switch pressed then the lamp slowly brought back to the balance point.
When the power (12 VDC <= 1 Amp) is turned off the lamp jumps up. That's to say the active magnetic circuit is pressing the lamp down and permanent magnets are pulling it up.
Note the "lamp" uses the new (2019) linear LED "filaments" and it rotates when on.
Fig 1 Mova Globe, Levitating lamp,
Plasma Globe, Novelty Electric Motor,
the Swinging Sticks Kinetic Sculpture is
just off camera to the right.
Levitron Arts is the patent holder.
500g Magnetic Levitation module
Patents3215901 Method and device for maintaining stationary position of a ferromagnetic body freelyfloating in electromagnetic field, Carniol Bohdan, 1965-11-02 - ferromagnetic rotor of an ultra-centrifuge, freely floats in the magnetic field of an elect-romagnet, coils above and below rotor. (but no to have a gap visible)
4585282 Magnetic levitation system, Robert W. Bosley, Levitron Intl, Filed: 1983-07-19, Pub: 1986-04-29 - active circuit Fig 1 coils above and below, but later figures show only bottom coil.
4910633 Magnetic levitation apparatus and method, Louis P. Quinn, 1990-03-20 - a magnet is held by an electromagnet above it, uses a sensor and variable lift adjustment to control gap, low cost, plans on internet, but touchy to get working.
5168183 Levitation system with permanent magnets and coils, Lorne A. R. Whitehead, University of British Columbia, 1992-12-01 - complex
YouTube: Inventing the Gravitron (LEVITRON From-Below Electromagnetic Levitator) -5218257 Magnetic levitation self-regulating systems, Oleg Tozoni, Maglev Tech Inc, 1993-06-08 - for trains all PMs
YouTube: Levitation Arts Levitating Light Bulb - support from below
YouTube: 2017: A MOUSE ODYSSEY - mouse climbs on floating disk (note: www.floatingstuff.com forwards to levitationarts.com)
YouTube: LEVITRON / GRAVITRON Technology From Levitation Arts
5404062 Magnetic levitation device and method, Edward W. Hones, William G. Hones, Creative Gifts Inc, 1995-04-04 - a PM top is spun over a PM square sheet then, using a non-magnetic lifter plate the top is raised. It will then hover for a little while.
5883454 Electormagnetic drive method and apparatus for driving a rotationally stabilized magnetically levitated object, Edward W. Hones, William G. Hones, Creative Gifts Inc, 1999-03-16 - spinning top floats for a while
6275127 Solar powered magnetic support for display, William Wallace French, 2001-08-14 -
6373676 Magnetic floatation control system,William Baker John, Span Inc (Hewlett-Packard),
7348691 Magnetic levitation apparatus, Harold Davis, Lorne Whitehead, Levitation Arts Inc, Filed: 2003-09-29, Pub: 2008-03-25 - much simpler 39 claims
7505243 Magnetic levitation apparatus, Harold Davis, Lorne A. Whitehead, Levitation Arts Inc, 2009-03-17 - 25 claims
WO2010150207A1 Floating lamp, Eberhard Waffenschmidt, Peter Visser, Philips, 2010-12-29 - floats above base, LED
Metal Earth makes laser
cut metal "bend the tabs" type 3D model objects. I got the
Monarch to see if the colors shown were part of the kit. (they
|Fig 1 Front of package.
Notice you can see metal sheet at top and in triangle notch at bottom left.
This is important when you cut envelope to remove metal sheet.
|Fig 2 Limited instructions.
|Fig 3 Metal sheet
||Fig 4 Assembled.
Tools for Metal Earth
From the video above.
Fig 1 Tools shown with Metal Earth Dozer (3 sheets)
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page created 7 April 2013.