Abstract: An improved thermal printer has circuits that are responsive to selected parameters of the printer and to the contents of a document to be printed to selectively enable the individual printing electrodes with printing impulses of varying energy depending upon when the electrode had printed. Other circuits cause the selective process to be responsive to whether electrodes adjacent a selected electrode had printed and how recently such printing took place. In different embodiments, circuits utilize not only the history of a selected electrode and its neighbors, the as yet unprinted portion of the document to be printed is utilized to aid in the selection of an appropriate printing impulse.

Abstract: A high speed media management device has tractor means for moving a web through the device past a plurality of work stations at each of which the web may be treated. Relatively high web tension is maintained throughout its travel path. Counting means near the beginning of the web path generate a count signal with the passage of each increment of web. The accumulated count signals are compared to numbers stored in a plurality of registers, each register associated with a work station and each containing a count representative of web travel distance relative to the work station. The first register count corresponds to the distance required to accelerate the web from a stop. The remaining registers store that count and a separate count representing the distance between the first station and the corresponding station. When the counter contents equals the count in a register, an actuating signal initiates a treatment activity at the associated work station.