Meaning
Classification under the Federal Communications Commission rules for products that contain internal clocks or oscillators but lack a transmitter. Compliance with unintentional radiator part 15b is required for nearly all modern electronic devices to ensure they do not interfere with licensed radio services. The rule covers everything from computer peripherals to high speed data routers.
Emission Threshold
Maximum levels for both conducted and radiated emissions are specified to prevent the leaking of electrical noise into the environment. Under unintentional radiator part 15b the device must be tested in a controlled laboratory setting to measure its noise profile across a wide frequency range. These limits vary depending on whether the product is intended for commercial or residential use.
Device Category
Components such as microprocessors and high speed memory buses are the primary sources of noise within this category. The unintentional radiator part 15b rules distinguish between class a devices for business and class b devices for home environments. Class b standards are more restrictive because home users are less likely to have the tools to mitigate interference from nearby electronics.
Verification Path
A manufacturer typically follows a self certification path known as the supplier declaration of conformity to demonstrate compliance. Maintaining a test report as part of the product record is mandatory even if the manufacturer does not need to file it with the commission. This document proves that the unintentional radiator part 15b requirements were met before the device was offered for sale.
