Don't forget, guys,that EVERY transmitter must meet the rules of operation and emission for your country, no matter how it is originally set up or modified.
In the USA, that means meeting the Part 97 FCC Rules. Note that ALL spurious emissions must be at least 43 dB below the transmitting frequency. The responsibility for measuring and verifying this lies with the operator -- that's you, the builder of the rig. You shouldn't rely on any given design. You must verify that it is within limits.
"(d) For transmitters installed after January 1, 2003, the mean power of
any spurious emission from a station transmitter or external RF power
amplifier transmitting on a frequency below 30 MHz must be at least 43
dB below the mean power of the fundamental emission. For transmitters
installed on or before January 1, 2003, the mean power of any spurious
emission from a station transmitter or external RF power amplifier
transmitting on a frequency below 30 MHz must not exceed 50 mW and must
be at least 40 dB below the mean power of the fundamental emission. For a
transmitter of mean power less than 5 W installed on or before January
1, 2003, the attenuation must be at least 30 dB. A transmitter built
before April 15, 1977, or first marketed before January 1, 1978, is
exempt from this requirement."
john
AD5YE