I'm trying to open some circuit schematics for some equipment I have in my lab. However, they were designed some time ago (2013) by an unknown technician with an unknown program. There are two folders, one called SCH (with file types .SCH, .NET, .ERC, .CMP, .CLN) and one called PCB (file types .PCB, .NET, .LIB, .CMP, .LST, .CNF, .ERR). If i try to open the .SCH file it's a binary, apart from a "Schematic FILE" header.
Does anybody have any clue about what program might have been used to make these? I've tried to open them with the Allegro viewer, but with no success.