With the advent of computer based electronics being utilized in automobiles, the Electromagnetic Radiation Subcommittee has deemed it prudent that a new test method be written to provide a common test for the measurement of narrowband radiation from vehicles and devices. This SAE Standard covers methods of measuring incidental narrowband radiation from vehicles and devices. The standard also establishes performance levels intended to protect nearby communication and broadcast receivers. It is intended to serve as an alternate method of measuring electromagnetic radiation which is analogous to the FCC Part 15 methodology but adapted to measuring vehicles. The equivalent procedures for broadband emissions are set forth in SAE J551. This standard covers narrowband emissions in the frequency range of 10 kHz to 1000 MHz. An example of such radiation is the unintended emission from on-board logic and computer modules. In particular, the standard is intended to provide protection to adjacent mobile communication and broadcast receivers (vertical E-Field test) and portable broadcast radios (magnetic field test). In the future horizontal E-Field measurement requirements will be considered.