Sketching unit for transmission of sketches and notes over normal telephone lines

摘要

A sketching system sketches first notes to be transmitted over a telephone line receives second notes from another sketching system. The sketching system includes a signal de-combiner device, receiving the second notes from the another sketching system and voice data as a combined signal via the telephone line and de-combining the combined signal into the second notes and the voice data. In addition, the sketching system includes a sketching unit connected to the signal de- combiner. The sketching unit includes a note displaying device displaying the first and second notes, a note generating device generating the first notes, and a processor connected to the note displaying and generating devices and to the signal de-combiner, receiving the first notes from the note generating device, receiving the second notes to the note displaying device. The sketching unit further includes a clearing unit selectively clearing one of the note displaying device and another note displaying device of the another sketching system and an erase unit selectively erasing the first and second notes displayed on one of the note displaying device and the another note displaying device. Finally, the sketching system includes a first lock device selectively preventing the processor from transmitting the first notes to the signal de-combiner preventing the first notes from being displayed on the another sketching system, and a second lock device for selectively preventing the processor from transmitting the second notes to the note displaying device.