The 300 bps MODEM was researched and is in the process of being designed and built. The relatively low speed of a 300 bps MODEM allows for an asynchronous design therefore eliminating much of the timing control necessary at higher speeds. The result is a low speed functional MODEM.
"300 Baud Modem Design,"
Journal of the Microelectronic Engineering Conference: Vol. 1
, Article 32.
Available at: http://scholarworks.rit.edu/ritamec/vol1/iss1/32