Make: "Mad scientist test-tube rack"


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The project uses a Feather microcontroller to shine UV LEDs into test-tubes filled with water doped with elements that fluoresce under UV.

Couldn’t you accomplish that with a device called a copper wire? How many microprocessors does it take to turn on a light bulb?


Relevant XKCD


But they flash on and off!

Kids these days, can’t flash an LED without a microcontroller.
Haven’t they heard of a 555 timer? Why when I was younger we had to use two transistors to make a multi-vibrator, and we LIKED it!
And before that we relays. They made a nice clicking sound.



Relays? Luxury! Why, we had to open and close the shutter on the lantern!


LANTERN! How well off must you have been.

We had a single candle we had to repeated light and blow out.

Edit: AND we were HAPPY about it.


Some unique cryptozoological foeti in each tube would be a nice finishing touch.


Oh, that’s perfect!


CANDLE?! Why we couldnt scrape together the earwax for one of those!

We had to beat each other senseless if we wanted to see flashing lights.


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