By 'tilt' I mean the observable tilting of the top and bottom of a square wave (or resulting modulated envelope) caused by low frequency roll off and non constant group delay through the transmitter in question.
That's why the transmitter frequency response, including transformers, should be essentially flat at least one octave above and one octave below the actual range of frequencies you plan to transmit.
For example, if you intended to limit your audio response to 150-4000~, the audio chain should test flat from 75 to 8000~.
Don k4kyv
