| 摘要 |
1,013,862. Character recognition; reading magnetic material density records; local head circuits. NATIONAL CASH REGISTER CO. June 12, 1964 [Aug. 12, 1963], No. 24541/64. Headings G4R and G5R. To convert a conventional magnetic recording playback head to read a record whose modulation is expressed as a change in reluctance due to the presence or absence of a magnetic material which may not be magnetized, such as a character 10 printed in magnetic ink, a high-impedance D.C. source 25 is connected across the coils 15, 16 wound on a core 14 of a transducer head to produce a stable flux condition across a gap 20. |
