What do you mean by "different pin number?" The BNC connector should be 10BASE2 on both devices, and you'll need five pieces for proper cabling: BNC T-connector (2), 10BASE2 terminator (2), 10BASE2 (RG-58A/U coaxial) cable (1). Attach the BNC T-connectors to the NIC and the HUB. Attach one terminator to each of the T-connectors. Connect the remaining open ends of the T-connectors with the cable. You've now built a simple Ethernet backbone.
terminator <- T-connector -> cable <- T-connector -> terminator
