Definitely not a vacuum tube:
It’s running the same firmware, though, with the Arduino Pro Mini and the LEDs drawing power from the (mostly) defunct lithium battery.
The LED holder is identical to the Pirhana holder, with a 10 mm diameter recess punched into it for the SK6812 PCB:
Those embossed legends sit in debossed rectangles for improved legibility. If I repeat it often enough, I’m sure I’ll remember which is which.
The 3.6 V (and declining) power supply may not produce as much light from the SK6812 LEDs, but it’s entirely adequate for anything other than a well-lit room. The 28 AWG silicone wires require a bit of careful dressing to emerge from the holes in the radome holder:
The firmware cycles through all the usual colors:
A pair of tensilized 22 AWG copper wires support the Pro Mini between the rear struts. The whole affair looks a bit heavier than I expected, though, so I should reduce the spider to a single pair of legs with a third hole in the bottom of the LED recess for the data wire.
The OpenSCAD source code needs some refactoring and tweaking, but the Pirhana LED solid model version of the battery holder should give you the general idea.
The Smell of Molten Projects in the Morning 