IBM Series/1 and question about ISA card

I just got an IBM Series/1! This is going to be fun, but it's going to take a long time to get running. It's filled with more dust than I've ever seen in a computer, and it uses 230v which means I don't have much of a choice of where to plug it into. And the manuals... That's going to take WEEKS to go through! But hey, I got four 200MB hard drives, a 4956-K00 CPU, a few I/O units and an 8 inch floppy drive out of it! Whheee! I LOVE those 8 inch drives! OK, thats going to take a while to sort through everything. On to the PC card. I found this strange 8-bit card labeled: Scan Doubler S/N 1179 PGS P/N8403001 It has two DB-9 connectors on the end, and it was pulled from an old PC. It's probably about a half length card. Any ideas on what it is? I was thinking some sort of dual-monitor video card... TIA