Jessica Hahn is looking for a job. Her contract with radio station KOY-FM in Phoenix expires Dec. 31 and the station says it won't be renewing her. Hahn, whose 1980 sexual encounter led to the downfall of PTL founder Jim Bakker, went to work for KOY during the summer, at first working the morning shift with other disc jockeys and then switching to the afternoons. Hahn had absolutely no radio experience before taking the job but says now she'd like to stay in the business.