Before revision: FC=DTL by Mullard FD=PMOS by Mullard FJ=TTL by Mullard (7400 series) FL=TTL by Siemens (7400 series) FP=HTL by Telefunken FZ=HTL by Siemens GJ=TTL by Mullard (74H00 series) GT=TTL by Mullard (74S00 series) Unfortunately the serial number does not specify the same type of gate in each family, e.g.
After revision: FY=ECL by SiemensFC=DTL by Mullard FD=PMOS by Mullard FJ=TTL by Mullard (7400 series) FL=TTL by Siemens (7400 series) FP=HTL by Telefunken FZ=HTL by Siemens GJ=TTL by Mullard (74H00 series) GT=TTL by Mullard (74S00 series) Unfortunately the serial number does not specify the same type of gate in each family, e.g.