The waveforms transmitted during the November 1994 Acoustic Thermometry of Ocean Climate (ATOC) project R/P Flip measurement used an m‐sequence phase modulated 75‐Hz carrier, two carrier cycles per digit. Because the source had an inherent Q of 5, the drive waveform was modified in order to produce a two cycle per digit output. This paper describes the basic characteristics of the source, the procedure used to broaden the source bandwidth, the enforcement of a source peak power limit, and shows the resulting waveforms. The received waveforms possessed small amounts of Doppler ‘‘shift’’ caused by the motion of Flip on its mooring. Doppler limits the amount of time over which receptions can be integrated. Doppler normally must be treated as time compression/expansion. However, if the Doppler is sufficiently small it can be treated as simple time shift. This paper compares the results of using both approaches to account for the motion of Flip. [Work supported by the Strategic Environmental Research and Development Program through ARPA.]