Homebrew Silicon-Carbide LED

Wow, that is interesting.

About how much light is produced? Is it easily seen in normal room light? For the area in your photograph is the apparent brightness about equal to, brighter or dimmer than the blue LEDs sometimes found as power lights on equipment? The photographs suggest that it is pretty dim butI can't tell from the pictures since exposure time could have been long.

The well-lit pix were taken with the room light on. In the second photo you can see the glow. It's pretty much what you see with the naked eye. Not very bright, but discernible. None of these are time exposures as such, just whatever setting the auto-exposure on my camera chose for the picture. In the last photo the dim light is from the hall light coming through the door.

Have you, or do you plan to raise the voltage? and if you do, what do you think the effect will be? What do you think the maximum results might be...

What you have here is an example of electro-luminescence. This is not the same as an LED. http://electroluminescence-inc.com/whatisEL.htm This site contains the exact definition of what you have built. The inclusion of silicon carbide is immaterial. It would be interesting to test resistance in both directions across the device to determine if there is some diode-like behavior.

well according to that link the brightness is controlled by the frequency....cool

Not electroluminescence. How to tell? The DC power source: batteries.

EL emitters are essentially lossy capacitors where the bulk of the lost energy is expressed as light. Go to that website again and look at the construction. Capacitors, as you know, do not conduct DC current (in an ideal world), only AC.

So what is it? Stay tuned...

I took your advice and made some measurements. I photographed the results so I could share them with you.

1. Diode test, pos to anode, neg to cathode. DMM shows OL (overload), so what is making it glow?

2. Same but with room lights dimmed.

3. Meter detail.

4. Meter detail.

5. Meter detail.

6. Diode test with leads reversed. Meter still reads OL, but glow is relatively dimmer. Why is there a glow at all? This is really strange.

7. Meter disconnected entirely. Still a faint glow. WTH???

8. Lights dimmed to see this effect more clearly. I'm speechless!

9. Zoom in on disk. Glow is obvious. This is beginning to smell like a hoax.

10. An AFD hoax, to be exact.

11. I'm sure of it. Uh oh, getting dim again; better hit it with more UV.

12. There, that's better.

13. Taking apart apparatus to see what's making the dang thing glow.

14. Hmm... glow on disk AND on screen. Must be because the screen is sticky on that side.

15. Lights dimmed to see glow more clearly.

16. Disassembled apparatus completely. Seems somebody forgot to strip the 'cathode' wire. And where is that copper cathode?

17. Better top 'em off again...

18. Much better.

19. Backside of SiC disk reveals that it is not SiC at all, but black conductive anti-static foam. That stuff you stick static-senstive ICs in?

20. Hmm.. The White Stuff is on one side only. Very suspicious!

21. The 'SiC disk' and aluminium screen pose together for the first time in the Light of Truth. Not a drop of toilet bowl cleaner was used, btw. The bottle seen in the earlier pix was merely guilty by association.

22. The Real Powerhouse behind the light: europium-doped strontium aluminate powders. White, Violet and Blue. Too bad the violet colour cannot be duplicated on a computer monitor. It's absolutely gorgeous.

23. Colours a coincidence? I think not.

24. Considered adding these other phosphors 'with increasing voltage' to walk it through the rainbow, but decided against it. Btw, EL lamps do change colour with increasing frequency, but the effect is over a fairly narrow range of wavelengths. I experimented with this effect in 1967 using a Sylvania 'Panelescent' EL night light - a very early EL lamp using a thin iron plate for one of the electrodes.

25. All together now...

26. Ready? Set?

Happy Poisson d'Avril Day!

I based this hoax on a very clever one which appeared many years ago in one of the electronics trade rags. Wish I could remember which one, but it's been many years.

Their hoax was of a simple, inexpensive technique for making efficient (>25%) silicon photovoltaic panels out of SiC sandblasting grit. Very inspiring article, prankwise, and very convincingly written to say the least.

Hope you enjoyed this little April Fool's treat and I hope to see someone improve on it next year! I do this very seldom, btw, so you're all quite safe from me meanwhile (for a few years anyway).

Cheers!

-e

And I'd already tried to sneak in a patent !

Ages ago I ran a 'Junk Yard Battery' thread. I can't help wondering if your LEd works in reverse too?
EG. In bright light does it generate a potential or current?
Del

I'll give it a try. Thanks!

Shameless self-pimping !

I still have the components for my entry, just never got around to putting them together. Is there still a prize ? The 50 or so cells I had lined up are fine, but the lemons are mingin'.

Nicely done!

Many years ago an Australian Electronics mag ran an article about a breakthrough called "PRINTEGRATED CIRCUITS".

You only needed to cut the paper based circuit out of their magazine, soak it in NaCl solution, attach wires and it worked as an amplifier (or something).

They recommended you hold the page up to a light first to observe the delicate circuitry. Unfortunately the "April fool" message was printed on the wrong page and many irate readers complained they'd destroyed their magazine but couldn't get the printegrated circuit to work.

Nice hoaxing.
So I can't build a self powered machine out of it?
Del
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Are you sure?

You'll need about a pint of HHO

Lemon juice works best.