Which of the following best describes one of the standards that must be met by an external RF power amplifier if it is to qualify for a grant of FCC certification?

  1. It must produce full legal output when driven by not more than 5 watts of mean RF input power
  2. It must be capable of external RF switching between its input and output networks
  3. It must exhibit a gain of 0 dB or less over its full output range
  4. It must satisfy the FCC's spurious emission standards when operated at the lesser of 1500 watts or its full output power