15.21 Information to user Any Changes or 『nodifications not 四pressly approved by the pa此y responsible f compliance c uld void the user's authority to operate the equipment. 。「 。 15.105 Information to user 。 This equipment has been tested and f und to comply with the limits fo「 a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits a 陀 designed to provide 「easonable protec目。n against harmful interference in a residential installation.