Nixie Clock ITS1A Manual page 22

ITS1A CLOCK
There are solder points marked GND, 3V3 and TX. TX should be wired to data-in on the first neopixel,
then you daisy-chain the rest together, connecting data-out to data-in.
The software is configured to drive up to 10 neopixels in groups of 6 and 4, so you can have
underlighting as well as backlighting.
One builder of this kit bought a bunch of neopixel modules like these and mounted them on short tubes
to stand them off the back of the board – You need the
WS2812B modules:
I also designed some tiles some small PCBs that take surface-
mount 3535 neopixels from PCBWAY. You will need to be
able to solder surface-mount components for these, and
then figure out how to mount them without shorting
anything out:
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