north drying circuit for the protection of data stored on a magnetic recording medium

摘要

1. A circuit arrangement for protecting items of data stored on a magnetic data carrier, in particular a magnetic tape, from the influence of the erasing or the recording head, as the case may be, during switching on or off of a device current supply, where the erasing current switch and recording amplifier are controlled via logic circuits, characterised in that a comparator (K1) precedes the erasing current switch (LS) and a further comparator (K2) precedes the recording amplifiers (SV), the supply voltages of which comparators exhibit their nominal value not only during normal operation but also whenever the logic circuits pass through an unstable range at switching on or off of the device current supply, and that the comparators (K1, K2) supply the erasing current switch (LS) and the recording amplifiers (SV) with inhibiting output signals (A1 and A2) when the supply voltage for the logic circuits lie below a reference value or when the logic circuits emit corresponding switching signals (E1 and E2).