Intriguing. That circuit board definitely looks like a little company's product from decades ago or a one-off - no silkscreen, single layer, "yellow" board material. Also, in the bottom right, it looks like there are some pads that have been left undrilled. As long as those three mains coloured cables in the bottom left aren't mains, it looks reasonable to keep running (there's not a lot of clearance between that area and the microcontroller...)

Also looks like it was hand assembled, by the component mounting. Wires soldered straight to board isn't great, but not a huge issue if stationary and undisturbed.