47 CFR 97.317 - Standards for certification of external RF power amplifiers.
(a) To receive a grant of certification, the amplifier must:
(1) Satisfy the spurious emission standards of § 97.307 (d) or (e) of this part, as applicable, when the amplifier is operated at the lesser of 1.5 kW PEP or its full output power and when the amplifier is placed in the “standby” or “off” positions while connected to the transmitter.
(2) Not be capable of amplifying the input RF power (driving signal) by more than 15 dB gain. Gain is defined as the ratio of the input RF power to the output RF power of the amplifier where both power measurements are expressed in peak envelope power or mean power.
(3) Exhibit no amplification (0 dB gain) between 26 MHz and 28 MHz.
(b) Certification shall be denied when:
(1) The Commission determines the amplifier can be used in services other than the Amateur Radio Service, or
(2) The amplifier can be easily modified to operate on frequencies between 26 MHz and 28 MHz.