K7DYY Super Senior 80- and 40-Meter Legal-Limit AM Transmitter

摘要

Thoughts of a "legal-limit AM transmitter" will bring to mind monster equipment, such as the classic 1 kW (dc input) Collins KW-1, at least to those of us who were interested in ham radio in the mid-1950s. For better or worse, many things have changed. Back then, the legal limit for all modes was defined as "1 kW dc input to the final stage of the transmitter." Such transmitters typically had an average carrier output of about 750 W. While dc input was easy to measure for an AM, FM, or CW transmitter, it was not so easy to measure on SSB in which the current varies with input voice level, resulting in confusion and misleading claims.