| 摘要 |
To obtain a good print quality in metal paper printers, the print current, after ignition of the arc, must be rapidly reduced to a fraction of the value necessary for ignition. For this purpose, two transistor power stages (T3, T4) are connected to the print electrode (2). Their partial currents form the print current, whose rapid reduction after ignition of the arc is obtained by the two transistor power stages being operated at voltages (U2, U3) of different magnitude. The second transistor stage (T4) is operated at a voltage (U3), whose magnitude corresponds to the drop in potential occurring upon ignition between the grounded metal layer (3) of the record carrier (4) and the print electrode. As a result, the second transistor stage is switched off when a diode (D) connected to it becomes non-conductive.
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