Transmission of data/sketch through telephone lines using gapping technique via a low cost telewriting equipment

Telewriting equipment is a low cost device that can transmit both voice and sketches. However, voice communication is temporarily cut off during sketch transmission. In previous research, the first author has successfully improved the equipment by interlacing the sketch with voice during the voice gap of the teleconversation. Since then, further enhancements have been added to the telewriting machine. Compressing the sketch reduces the loss of voice and data during transmission. Also, the additional features of an improved control pad system and an auto-send detector create a more effective and user-friendly machine. The user has the choice to save, erase, hold, print or re-send the sketch of a particular file location. Sketches can also be transmitted through an auto-send detector on the writing tablet without pushing the 'Send' button.