Introduction: U-M-R-O: Uranium-glass-marble-ring-oscillator

About: I love to invent and create new things in a "steampunk styled way" working with brass, copper, vulcanized-fibre, brass gears and (ply)- wood. On one side I am fascinated in neon lights and small ele…

Hi everybody

Today I want to present you the famous and incredible „uranium glass marble ring oscillator“ (furthermore called: UMRO)

This project started two years ago in July 2017, when I first saw such an glowing and rotating object at you tube made by some guys from the Edinburgh Hacklab.

Immediately I just wanted to build this more than anything else and so I started my investigations.

Next information was a small description at hackaday by Daniel Rojas and the additional thread.

As third step I came into contact via email with "Wilhelm Klein", at that time a member of dimsumlabs, Hong Kong and he kindly answered my upcoming questions about building such a ring-oscillator. He also sent me some sheets from a workshop with building instructions.

In these „Hong-Kong-papers“ I also saw a very funny and extraordinary schematic which I used as a template for my own presentation because this ringcircuit drawing from „Ellindsey000“ is so clever and cool.

I want to give credits to all these guys for their famous idea !!!

Take a bow and thank you so much!!

While studying the instructions of Wilhelm Klein, a lot of new technical questions rose up and I decided first to find a good answer or better solution of them eg. how to minimize the use oft the soldering iron to avoid heat damage of the electronic parts and also simplify the assembly steps. Well then I first tried to order the necessary electronic parts (see list) and realized that the providers mostly offered only a100 pcs. packs. So I decided to build about a dozen of these UMROs and integrate them with my upcoming steampunk objects.

First object is a steampunked metal case to keep my first UMRO in, it will be shown at the end of this instructables project description.

And here is the result of this thinking and making process and I try to explain in my following very detailed descriptions:

-How to build such an UMRO in quite an efficient and easy way

-How to get the best rotating light effect inside the uranium glass marble

-How to change the rotation-speed, should it run a little more slowly or faster without changing already build in parts

-How to realize the direction of the rotating light effect (clockwise or counterclockwise)

-How to build such uranium glass marble ring oscillator by using an „external“ pcb with all electronic parts except the UV-LED and

-How to combine two or more of such marble-rings by using the necessary electronic parts (except the UV-LEDs of course) only one time either integrated or on a separate pcb and rotating with the same or a an opposite spin!!

Last but not least we have to mention the troubleshooting.

And now let us start with this instructable. Hope you enjoy it and if you like it please vote for this project at the make it glow contest!!!

With many greetings to all readers

Yours Aeon Junophor

Step 1: Parts and Tools-Lists

Parts list:

To build one UMRO you need:

1 pc Uranium glass marble ø 20 mm shop

7 pcs UV-LED (5mm 390-395 nm about 3000 mcd) ebay-shop

7 pcs 2N7000 DIO Transistor TO92 TEM

7 pcs 300 R resistorTEM

7 pcs 0.47 µF ceramic capacitor pitch size (470 nF, means the same) TEM

7 pcs Resistor: 33K (for very fast rotating), or 100K (for very good rotating), or 200K (for very slow rotating),TEM

1 pc alkaline block battery 9 Volts ,

1 pc battery clip ,

Insulated small copper wire, e.g an loudspeaker inductor from scrap

about 10 cm lacquered copper wire ø 0,85 mm to cover LEDs,

about 80 cm thick copper wire for the small and big rings. from a scrapyard,

70 cm shrinking tube.

Tools you need:

Electronic pincers

Small Pliers

Cordless screwdriver

Solder iron and solder

Small File

Small knife

Wire stripper

Small screwdrivers

A „third hand“ if necessary with a magnifying glass

A piece Plywood from scrap.

More helpful tools:

Some Drills of different size

1 Forstner drill 18mm and 22 mm

Some wooden toothpicks

1 pc 20 Euro cent coin or a paperprint

A ring sizing stick or another conus that might fit

Small stick made of wood or metal with a similar diameter of the LED to wrap the coils for the UV LED.

Step 2: Schematics and Theory

You might ask me: „Why using an uranium glass marble and UV LED?“ Well the answer is really simple. Uranium glass shows a very strong fluorescence effect when UV light with a wavelength between 360 nm and 405 nm is used. The peak is about 395 nm. No other material mixed with glass shows such light in that impressing way.


Uranium glass is glass which has had uranium, usually in oxide diuranate form, added to a glass mix before melting for coloration. The proportion usually varies from trace levels to about 2% uranium by weight and its radioactivity is of a very low alpha-radiation (about 60 Becquerel or 0,35 mSv/a). You can compare this alpha-radiation emission with the level of background radiation. The skin of your hands is already protection enough. Your clothes protect you also in the same way too. But take care, that you do not incorporate uranium glass parts or a whole marble. There is no danger when you carry the UMRO in a transparent plastic bag in your pocket but you can also create a stylish small box case made of wood or metal with a small window of acrylic or real glass like I have done it and will show it to you at the end of this instructables.

The ring oscillator circuit:

Wikipedia writes: „A ring oscillator is a device composed of an odd number of NOT gates whose output oscillates between two voltage levels, representing true and false. The NOT gates, or inverters, are attached in a chain; the output of the last inverter is fed back into the first.“

This is the basic description of a ring oscillator circuit. And now I follow the ingenious step which was made by the members of the Edinburgh Hacklab and the other guys who already built this: They changed the sequence of these inverters in that way that one get the impression that inside the glass marble a light-beam is rotating. These inverters run very fast and that is why you need a capacitor and a resistor to lower down the speed. The ceramic capacitors are a little bit more expensive then the resistors, so I chose to keep the 470nF capacitor and changed the amount of the resistors to find the best speed. You can use every resistor between 33 K Ohms (very fast rotating) up to 200K Ohms (very slow rotating). To my opinion 100 K Ohms work best in this case.

I then tested different combinations between the inverters (in practice: whether to skip one, or two or three LED and turn these skips in left direction or in right direction as you will see at the schematics) to find out which will the best sequence to create a harmonic rotation for the beam and and while I was doing this suddenly the rotation changed its direction. I was very surprised and found out how this worked. So I can show you now the schematics for running around clockwise or counterclockwise and will show you in the next steps how to manage this in practice. Famous creator „Ellindsey000“ got the ingenious idea to draw the schematic as a closed ring-circuit. I have never seen such a cool ring-schematic before and I took it as a template for my own drawings because this ring-schematic explains the „secret“ in a very cool way. If you want to solder the electronic parts of such a ring oscillator on a seperate strip board and only connect UV-LEDs from the uranium glass marble ring to this board , I drew this schematic too. In this case it is not necessary to define the direction of the beam on the board because you can change the direction of the rotating in placing the LED from number one to seven clockwise or the other way round.

This circuit runs with 9 V Battery but I also testet only 4.5 Volts (3 AA.batteries) and was really surprised that it worked too. The rotation speed was a little bit lower and the light of the UV LED too. So you can control the speed with a rotary potentiometer. Try it!!!

Step 3: Preparing the Copper Coils and Rings

As I told before, I planed to built some of these UMROs and that´s why I have to create all parts ten times more. So in my description I will give you the right number to built one UMRO, but at the pictures you sometimes see more pieces than needed.... First I take a small wooden stick with the same diameter of the used UV-LEDs. With a cordless screwdriver roll up a coil with about 10 cm length. lacqured copper wire works best (I took a wire with ø 0,85mm) but every other copper wire will work as well. Then cut this coil into 10 pieces and choose the seven ones you want to solder.

If one coil is overheated by your first attempts you still got pcs as substitute. It is up to you whether your coils are about 9, 10 or 11 mm long. For the two small rings around the marble, first measure the diameter 2,5 mm above the middle. A ring size stick is very helpful for this and I experienced that the diameter is between 19 and 19,5 mm (see picture). The big ring around the LED leads measures about 45 mm in diameter (depending of the length of your small coils for LED). This ring can be braided, twisted, woven or just kept straight. I kept this ring straight and it´s diameter was about 1 mm.

Step 4: Solder the Coils

To solder the rings around the marble and attach the seven small coils in a Heptagon it is very helpful to prepare a piece of plywood first. Mark the center of the plate and draw a circle with diameter of the 20 euro cent coin (22 mm) or drill a hole carefully only half a millimeter deep with a 22 mm forstner drill. Now place the 20 euro cent coin (or a paper print of this coin) in this center and the seven notches. The draw the seven lines from the center through the notches and there you are with the center lines for the coils. In the same center of this plywood plate drill now a hole around 10 mm deep with a forstner drill ø18 mm. Then drill in the middle of this hole another hole ø 2mm if you use a marble with a hole so you can fix it with a wooden toothpick. Now put the first small copper ring at the center of the plate and place the marble on it. Fix it with a toothpick. Now solder one coil after another to this ring so you get a heptagon. If you use a lacquered copper wire you first have to file the end of the copper wire so you can solder it. It is very helpful to use a small piece of a wooden popsicle to put it into the coil and keep it in its position while fix it with solder. After soldering all 7 coils put the second small ring on the marble an solder the coils to this ring again.

Step 5: Ad the UV-LED


Test every UV-LED before you use it. For testing take your 9 V-battery and one of the 300R resistors. Then test the LED.

Now screw one LED after another into the coils so that all long leads (Anode) can be soldered to the big ring around.

After being attached to the big ring cut the overlaying "Anode-leads" off.

Step 6: Pepare the Electronic Parts and Solder the Modules In

First take the 2N7000-DIO transistors and bend the left and the right lead as shown at the pictures.

The second step is to solder the ceramic capacitor to the source and Gate leads.

Next stepp is to solder some 4 or 5 cm of insulated wire to one lead of a 100K Ohm resistor and insulate it with a small piece of shrinking tube. Then solder the other lead of this resistor to the Gate lead,

Do this six times again and the main work is done!

Next step is to solder this prepared module with the source lead to the small ring around the marble as shown in the pictures. Repeat this step until all seven modules are integrated.

Then you have to solder the 300 R resistors to the cathode lead from the LED after this leads had been bended towards the innerside (see pictures) The other lead must be attached to the Drain lead of the transistor. Keep this lead connection long.

Step 7: Clockwise or Counterclockwise? Choose the Rotating Direction

To finish the Uranium glass marble ring oscillator U-M-R-O you just have to solder the other end of the insulated wire to the drain lead of a certain transistor. Choose the direction: clockwise or counterclockwise of the rotating beam which will be seen when you look at the frontside of the U-M-R-O!! You can read at thew list of the schematic which Gate has to be connected to which drain. It is very helpful to take another plywood plate drill a hole of 18 mm in the center and fix seven screw terminals around, so that you can put in the overlaying leads of the drains.Then take one wire after another and connect them as described. After this step make a test whether the U-M-R-O runs. Therefore connect the positive wire (red) of the battery clip to the big ring and the negative one (black) to the small ring around the marble. If you now attach the battery the light starts to rotate.

If you are successful, you can unscrew the wire and solder ist one by one to the right drain and that is it!

If not start your trouble shooting:

Mostly one of the Gate leads might get into shortcut contact with the inner ring. You will then see that only some lights are shining permanently the others not and there is no rotation. Just bend the Gate lead a little bit to the outside and it works. The same might happens if you didn´t soldered the source leads carefully to the inner ring. Test it and solder this lead again if necessary.

Congratulations you have finished your project!!!

Step 8: Solder Parts to Pcb

If you want to create another object and you need the electronic parts unseen, you can also solder them to a separate pcb and just connect the LED with wires to it. Here I show how this works. It is quite simple as you will see at the pictures and you choose the rotating direction by the way you put the seven LED into the coils around the marble.

It is also possible to combine two LED in parallel so that you can drive two rings with one pcb or one set of electronic parts integrated in one ring and the other one runs free. You can let them rotate with the same direction or in the opposite direction.

Step 9: Steampunked Metal Case

A steampunked metal case for presenting an UMRO is necessary because it protects the first Uranium glass marble ring oscillator made by Junophor against damaging while carrying and presenting

I used the metal casing of an old german handlamp Type No. 414 from DAIMON which was used in the 1960s by the german federal police. You can realize this by this typical green-blue colour. I got this broken torch from the scrapyard and after cleaning and repairing this small box I modded it with very old electronic parts like resistors made by Siemens & Halske from the 1930s to a stylish Steampunk safety-box. The UMRO now can be carried safely an taken out for presentation.

Hope you enjoyed this detailed description

and please vote for it.

Good luck to your hopefully countless own uranium marble ring oscillators!!

Yours Aeon Junophor

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