From Jim Haynes 1/23/20 posting on greenkeys a couple of years ago….
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The shift was +/- 18 Hz to stay within the FCC requirements that the
carrier frequency be within +/- 20 Hz of the assigned frequency. The
baud rate was 75 and the demodulator was said to be one designed for
85HZ shift.
Earl E. Selover, David A. Griffith, John R. Martin, and Donald Spector
Use of Commercial Broadcast Stations for Emergency DOD Communica-
tions. IEEE Transactions on Communication Technology COM-15:4, Au-
gust 1967, p. 579.
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