FCC Part 15 — Unintentional radiators

What this standard covers and how we test it

FCC Part 15B governs unintentional radiators: any digital device that clocks above 9 kHz and is marketed in the United States. Since 2017 the route is the Supplier's Declaration of Conformity rather than a certification filing, so there is no FCC ID - but there is still a full test report and a signed SDoC that must be produced to the FCC on request.

The measurements are:

• Conducted emissions on the AC mains, 150 kHz to 30 MHz
• Radiated emissions at 3 m or 10 m, 30 MHz to 1 GHz, and above 1 GHz when the highest internal clock exceeds 108 MHz
• Set-up and cabling per ANSI C63.4, worst-case operating mode
• Labelling, user information and the SDoC statement itself

Testing is done on a representative production unit with the cables and adapter that ship with it. A device measured alone frequently passes, then fails on the radiated set-up once the supplied power supply is added - so we ask for the retail configuration, not a lab bench sample.

We normally test FCC Part 15B together with 47 CFR Part 15: one sample set, one set of test dates, and a single report pack that the declaration of conformity can reference.