I’m not sure why these have disappeared from the site, other than possible malicious activity given the bots that are now posting about Dubai adventures and gambling….
https://web.archive.org/web/20230323082707/https://gra-afch.com/downloads/schemes/schemes-for-mcu/mcu-board-ncm109-v1-1-for-nct4xx-universal-control-board-for-nixie-clocks/
The above is a link to the schematic for the NCM109 control board. I am making an assumption that this is the control board that you have based upon the NCT### that you listed.
You are looking for the three switches that are along the bottom of the schematic, just right of center.