Abstract: An apparatus and method for reproducing pit information precisely from a magnetic optical disk without being adversely affected by heat accumulation. The signal reproducing apparatus reproduces signals using a neural network constituting a decoder that decodes pits on the disk. The signal reproducing method provides learning using a sigmoid function and carries out signal reproduction using a step function.

Abstract: A multistylus head device which comprises a vast plurality of insulated wires embedded in an insulating substrate having through-holes. The present multistylus device is characterized in that the insulated wires have their respective free terminals exposed on one edge of said insulating substrate and disposed in parallel at predetermined equal intervals in close proximity to each other to form electrodes and have their other terminals exposed respectively on the inner walls of said through-holes; and said other exposed terminals of the insulated wires are connected respectively to metal layers electrolessly deposited on the inner walls of the through-holes. The present multistylus head device is compact in size and excellent in reliability of terminal connection and is capable of recording a transmitted information with high density of printing.