What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHz?

  1. At least 43 dB below
  2. At least 53 dB below
  3. At least 63 dB below
  4. At least 73 dB below