neilp It looks like two 4017 decade counters, one for X and one for Y, each will cycles through a count to ten with one row or column lit at a time. The little 8 pin chips could be 555 timers producing a clock signal for the counters. The variable resistors will change the clock frequency and allow different lighting patterns. A little like a 2D “knight rider” Larson scanner.

The seller 10*2.7*1.38 in

CarManBy I have no idea

CarManBy I have no idea

wangxifen no function

Della https://lighthouseleds.com/blog/polarity-guide-of-0402-0603-0805-1206-and-most-all-smd-leds.html

Meatusreff Weld according to the position in the list.

xiaohui Try Raspian system