Authenticating digital audio is a crucial task for audio forensic technicians (AFT) owing to increased use of digital multimedia in litigation. Analysing the electric network frequency (ENF), which can be unintentionally embedded when recording digital audio, is a critical authentication tool. Increasing use of digital media in court means growing demand for AFTs and raised demand for education. Thus, ENF analysis should be key in the education of future audio forensic technicians. A device for educational purposes has been designed to demonstrate the technology and procedures involved in ENF analysis, providing future AFTs practical experience in a key authentication technique.