Playback preamplifier for magnetic tape recordings
US4524396A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 1983 |
| Grant date | Jun 18, 1985 |
| Priority date | — |
| Expiry date | Aug 19, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
For every playback head (6) on the head wheel (1) a sector (5) of the head wheel disk carries a preamplifier consisting of two amplifier branches operating in phase opposition, each having an input transistor stage of the grounded emitter configuration and an output transistor stage of the grounded collector configuration (sometimes referred to as an emitter follower). Both stages have voltage negative feedback. The outputs of the amplifying branches are respectively connected to opposite ends of a rotary primary coil of a multiple transformer serving to couple the rotating preamplifier circuits to stationary outputs. Blocking capacitors prevent the flow of equalizing currents in the event of any deviations from electrical symmetry. The circuit is usable for playback of recordings in the form of digital signals picked up at a rate of 2 megabits per second.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.