A facsimile system has improved features for receiving copy medium and for printing. The system has a cylindrical rotatably driven drum that has an expansion device that allows the drum to expand its effective diameter. When the unit is used as a receiver, a cylindrical loop of copy medium is inserted over the drum, when the drum is in its reduced diameter position. Then the expansion device is actuated to enlarge the diameter and tightly constrain the copy medium. The same device may be used to transmit, since the expansion device utilizes a slot formed along the periphery of the drum. The slot opens to receive the edge of an original document when the expansion device is in the reduced diameter position. The slot closes to retain the document when the expansion device is rotated to the enlarged diameter position. The printing is accomplished by a solenoid actuated hammer that presses a ribbon against the copy medium while the drum rotates.