Trial Construction of a PCM Recording Adapter (First Report) : On The Design and Operation of the Recording System

A recording and reproducing circuit has been constructed as a PCM audio recording adapter which can be used in conjunction with the usual home type video tape recorder. This report describes the design and operation of its recording part. In order to realize two channel, 20kHz band recording having a dynamic range of 70 dB or more, the PCM sampling frequency of 44.1kHz and the quantized data code of 12 bits/sample were selected. Four check bits were added to the data code to detect the code error. The group of 130 bits digital signal including 96 bits of data and check bit for 3 input signal samples, data synchronizing pulse and video horizontal synchronizing pulse were recorded with a bit rate of 2.0475 Mbits/s within one horizontal scanning period on the video recording tape.