前言在毛主席革命路线指引下,我国磁性记录材料有了较大的发展。为了满足电子电讯技术发展的需要,近几年来,我厂研制了几种盒式磁带。1973年5月1日,我们试制出第一盒 C-45型盒式磁带,经有关单值试听后,提出了宝贵意见,我们又进一步改进,使质量达到了使用要求,同时开始小批量生 Foreword Under the guidance of Chairman Mao’s revolutionary line, there has been a great development of magnetic recording materials in our country. In order to meet the needs of the development of electronic telecommunications technology, in recent years, I plant developed several kinds of cassette. May 1, 1973, we trial production of the first box of C-45-type cassette tape, after the relevant single audition, made valuable comments, we have further improvements so that the quality to meet the requirements of use, and begin small batch