Instructables

Table for Electronic Dreams

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Picture of Table for Electronic Dreams
Table for Electronic Dreams is a table which reveals the hidden electrical activity of nearby electronic objects. Through this interaction, people will develop a greater awareness of the invisible workings of their electronic devices and the limits of human perception.


 
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Step 1: Gather parts!

Picture of Gather parts!
You will need:

PARTS LIST

15 circuit boards
15 LM324 quad op amp
15 14-pin sockets
60 white LEDs
60 induction coils*

* Currently I am using coils from Digikey part number M10013-ND. The inductance is 4.7mH. They do not look like the ones pictured in this instructable.

60 10 ohm resistors
60 10M ohm resistors
60 1K ohm resistors
30 100K ohm resistors
15 10 μF capacitors
60 0.1 μF capacitors


You could change these numbers if you want to make a smaller table. There will be 1 quad op amp, 4 LEDs and 4 induction coils for each board.


For the table:

1/4 inch translucent white acrylic 33" x 21"
1/4 inch clear acrylic 33" x 21"

aluminum u-channel


For op amps I am using a quad op amp LM324, but you can use any op amp chip.

Step 2: Plan circuit

Follow the schematic and connect the components properly.

You can do this on a perfboard or a printed circuit board if you want to be fancier. I am selling printed circuit boards , please see my website for details on ordering boards.

Essentially the coil picks up a voltage, which is amplified by the op amp, which drives an LED.

I have placed the coil next to the LED so there is more of a one-to-one correspondence between detected field strength and LED brightness.

See a legible version of the circuit diagram here: http://andydoro.com/table/images/circuit.gif

Step 3: Assemble circuit

Picture of Assemble circuit
Assemble components onto a printed circuit board.

You can also use perf board.

The board should run on between 3 to 5 V DC current. Use a voltage regulator (7805 or 3940) in order to get a steady voltage.

Step 4: Test the board

Picture of Test the board
Oh look, it's working!

Step 5: Repeat!

Picture of Repeat!
You can keep making circuit boards!
gandini432 months ago
hi....i'm new here...how can i get the schematic of this cool stuff (gandini43@hotmail.com)
gandini432 months ago
hi....i'm new here...how can i get the schematic of this cool stuff
mbenavides4 months ago
you should include a pin by pin, i have tried nearly every possible configuration and none seem to work
Hi, What is the total power supply used for the entire circuit once all the seperate circuits are connected?
maixy2 years ago
which symbol represents the coil?
(i am a fish...~_~)
My unit works but no longer works when I use a wi-fi or bluetooth. What do you use the coil? 470UH or 1000UH?
Sorry for my English.
How did you rectify your problem.... ( LEDs always on) ???
hi i plan on buying the induction coils from http://www.digikey.ca/ could anyone paste the part # or link as to which one i should order for this project.

thanks
Hi snoopdog416 My son and I have been experimenting with the circuit and we were struggling with the best coils to use. I can advise now that in our experience it dosent appear to be a big issue what coils you use. We have managed to get the circuit to work using a wide range of coils and even got it working with a small section of straight wire in place of the coil !! Please note our test circuit was set up on a bread board using a number of small connecting wires. The small connecting wires may have had an impact on the sensativity of the coil. If I was you I would test your circuit with a cheap coil or section of wire before I purchased 60 new coils. Cheers D McC
thexplanet DMcC4 years ago
Hello DMcC,

Thanks for pointing out regarding the 3-cm wire in lieu of 4.7mH inductance coil,

however, can you please share the snap /picture of your bread board setup for this,

as I want to make this, and i am not that good into electronics, and i see this is dual sided PCB.

so, i would like to test it on bread-board first.

Thanks in advance.
DMcC thexplanet4 years ago
Hi thexplanet

Unfortunately I have moved home since I played around with this circuit (back in June 2009) and dont have ready access to the breadboard.

I would  recommend that you set up the circuit a replace the coil with a short section of wire and see if that works for you. My son and I discovered that a short section of wire worked quite well as a replacement for the coil.

good luch
D McC
thexplanet DMcC4 years ago
Thanks DMcC,

I did the entire re-design of this ckt, and got it working for an Inductor with 4.7uH

can you explain which mode is the LM324N is working in? or why is it only LM324N? being used.

Is it RF / Microwave or EM?

Thanks
Can you please post the redesign of the circuit ???
Hi DMcC Thanks for you input, I really have no experience using induction coils. I would appreciate it if you could perhaps paste a couple links from digikey.ca as to what coils would be appropriate for this project and then i could order a select few and experiment with them before i purchase a large amount. There are so many types on digikey that its overwhelming! thanks
Hi snoopdog I have had success with the following coils from a local company
http://www.altronics.com.au/index.asp?area=item&id=L8260
http://www.altronics.com.au/index.asp?area=item&id=L6230
But as mentioned in my last post I don't believe it really matters what coil you use as we also had success with using 3 cm of wire in place of the coil.
If you set up a test circuit on a bread board you will see for yourself that the coil rating is not important.

All the best
D McC
The LED's are always on..... When I bring a cell phone in, LEDs are flickering.... Can anyone suggest what should I do???
nimit19942 years ago
the minimun order for the induction coils from Digikey is 1000 which is too high and too expensive. Does anyone know where i can get the induction coils needed?
ilpug2 years ago
Amazing. So, have you found out whether or not cell phones dream of electric sheep?
mr panerai3 years ago
hi....i'm new here...how can i get the schematic of this cool stuff (or maybe anyone selling the pcb completely with all componens (how much it cost?)

all email are welcome sekutu@hotmail.com / tomz_eternity@yahaoo.com
andydoro (author)  mr panerai2 years ago
Hi. The PCBs and components are available as kits from my website: http://andydoro.com/table/order.html
To make the board more sensitive do you just make a larger coil of wire?
ram.pai3 years ago
hey can any one send me EAGLE files plzz???
ohalpaul3 years ago
Hi great project i'm thinking of making a coffee table like this .
CCOTTER2473 years ago
I was curious if you could post the eagle files please!!!!
akumasenshi4 years ago
Can the LEDs be replaced with colour changing LEDs? I haven't studied electronics for a few years. The idea would be for the table to "shift" colour/s
I'm not sure, but it would be cool (and very difficult) if the lights changed color depending on how much of the "electricity" was given off by the device near it.
andydoro (author)  JChevin4 years ago
I was thinking about this possibility.
 Did anything ever come about with the RGB LED's? Looking at actually making a wall out of this design.
you would need to buy RGB LEDs that change through their colours depending on the voltage/current that is applied to them. eg, low current = Red, mid current = Green, high current = blue, and every shade in-between and vice versa.
It would be easy! You would just replace the leds with the RBG ones. The table is meant to change in brightness when the circuits induct more or less. Instead of getting brighter and dimmer, it would get bluer and redder!
are you talking about the RGB LEDs that have two legs or four legs? if you are talking about RBG LEDs with two legs do you know where i can get some because i have a project in mind and i cant seem to find any, not sure if two leged RGB LEDs even exist? if anyone can help me out on this it would be great, CHEERS!!
railrun3 years ago
Hi, I 've tried to build one board, but it didn't work. It seems, that the coil isn't correct. It's similar as you name here with 4,7 mH. Isn't it to high?!
Could you upload the eagle file for the board?
chionatan4 years ago
Hi, I would like to know, too, how to make the coil. I bought some copper.Could you give me some hints?
aafaquehs4 years ago
hey at least tell what size are the induction coils or instruct how to make em..
RetroTechno4 years ago
Pretty nifty idea. This basic idea could be the start of all kinds of cool projects. One little thing -- in looking at your schematic, I noticed you used capacitor symbols for the coils. Shouldn't they be inductors instead? Anyhow, they were clearly labeled, so no big whoop.
andydoro (author)  RetroTechno4 years ago
Hello! Yes, I should point this out. I used a capacitor in the circuit board program to leave a big circular footprint for the coils.
LED always on :/ what wrong? i'm change lm324 but don't work.
Sorry on my english
you might want to check your resistors some might be bad or your ic  may also be bad. also makesure you power supply isnt to high if your current is to high it may effect all of those
the schematic the IC ground and Vcc (power supply) are not attached thats pin 4 ground and pin 11 needs to go to the powersupply
i had the same problem. prototyped it with a battery and it worked fine. but when i hooked it up to a 12v wall wart transformer with the 7805 they would all just stay on. what worked for me was to add the buffering capacitors to the input and output on the 7805. played around with the values of the capacitors for a while. but it fixed my problem. good luck.
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