This figure illustrates the timing of elements of CCW
communication. The enable shows the pressing of the key by
the human operator. Note the dots and dashes are not precise
in length, spacing, or timing. The CCW keying shows the keying
as sent by the CCW keyer. Note a dot is begun only at the
beginning of the pulse period and continues for the full
period. The signal IS transmitted as RF pulses for the
desired periods. As received, the signal is weakened and
mixed with QRM and QRN. In the CCW filter the signal is
rectified to a DC voltage by the mixer. The integrator
sums the power (voltage) received over the period. This sum
is held for the next period. The audio out represents the
conversion of the recovered modulation back to an audio
signal of frequency convenient for humans.