Detection of transmission errors in 5-level punched tape

Business concerns in this age of automation are making steadily increasing use of their leased telegraph systems for the transmission of data in 5-level tape form. The number of errors introduced in the data by transmission over high-grade facilities is relatively small and can be tolerated in many business applications. In some situations, however, the error frequency must be reduced to the lowest possible rate. For these situations the telegraph company has developed equipment which will incorporate redundant check characters in the data at the transmitting end of the circuit and perform the check and delete the check characters at the receiving end.