Can anyone identify these boards? Person I got them from can't remember anything about them. http://www.pdp8online.com/ftp/misc/unknown_boards/
Date codes of 1964. Size 4.5"x3.25". Looks like used card edge for keying but has separate 23 pin connector for electrical connection. No useful markings I can see. Has card ## on the back. Search by picture didn't find anything. Thanks
