[Code of Federal Regulations] [Title 47, Volume 1] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 47CFR15.21] [Page 758] TITLE 47--TELECOMMUNICATION CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION PART 15_RADIO FREQUENCY DEVICES--Table of Contents Subpart A_General Sec. 15.21 Information to user. The users manual or instruction manual for an intentional or unintentional radiator shall caution the user that changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. In cases where the manual is provided only in a form other than paper, such as on a computer disk or over the Internet, the information required by this section may be included in the manual in that alternative form, provided the user can reasonably be expected to have the capability to access information in that form. [54 FR 17714, Apr. 25, 1989, as amended at 68 FR 68545, Dec. 9, 2003]