Part 15

Code of Federal Regulations, Title 47, Part 15 (47 CFR 15) is an oft-quoted part of Federal Communications Commission (FCC) rules and regulations regarding unlicensed transmissions. It is a part of Title 47 of the Code of Federal Regulations (CFR), and regulates everything from spurious emissions to unlicensed low-power broadcasting. Nearly every electronics device sold inside the United States radiates unintentional emissions, and must be reviewed to comply with Part 15 before it can be advertised or sold in the US market.

Subpart A includes 21 sections from 15.1 to 15.38.

47 C.F.R. 15.1b states that any radiator (that which emits radio energy), whether or not intentional, must be licensed unless it meets 47 CFR 15 or is otherwise exempted by the FCC.

47 C.F.R. 15.3 the definitions are defined by the definition given.

47 C.F.R. 15.5 contains a general provision that devices may not cause interference and must accept interference from other sources. It also prohibits the operation of devices once the operator is notified by the FCC that the device is causing interference.

47 C.F.R. 15.5d prohibits intentional damped wave transmissions, which were common before the 1920s but cut across large sections of frequencies.

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