Code error overlaying in digital transmission signals

摘要

For checking transmission and monitoring devices of digital transmission links, it is known to overlay code errors into the digital signals to be transmitted. In accordance with the invention, the code errors are overlaid such that given the prerequisite of a redundant transmission code, no falsification of the informational content of the digital signals arises. In accordance with the invention, this is undertaken in that the mode condition in the connected mode memory is modified and output to the mode input of the code conversion logic as a new sequential mode.