That's not a Chicago Schwinn. Japan or other import maybe by Giant. If it is a Schwinn, the build date should be stamped on the head badge.
See if this site's info helps. http://re-cycle.com/History/Schwinn/SwnB_Serial.aspx
Thank you for the site reference. This helped - turns out to be a Taiwan made Schwinn - Circa 83. Serial number is on the right rear axle. The head badge does say Chicago Schwinn.