The apparatus for manufacturing a wiring substitute comprises a transporter having a circuit where a sheet is circulated; a screen printer for printing a conductive paste on the sheet; a counter for counting the number of times to print the conductive paste on the sheet; and a distributor for ejecting the sheet from the circuit when the counted number reaches a preset number. The density modifying ingredient may be selected from the group consisting of complex carbohydrates or humectants. If the output assistance is permitted in any mode, the maximum amount of assistance is selected, and a previous value of the maximum amount of assistance is compared with the current value of the maximum amount of assistance. Predistortion coefficient values may be computed based on measured results in the select channel.