| 摘要 |
Bipolar digital repeaters are commonly fed with a constant d.c. supply but with the known circuit, the mode of use of transformer-coupled output stage places a limitation on the voltage-amplitude of the output pulses. The 120 M bit/s data transmission system may occasionally require to have its repeaters operate over line-sections of exceptionally high attenuation. The proposed circuit is intended to meet these requirements, using modified connections to the transformer (3 equal windings) and minimal additional components, the maximum peak-output voltage is consequently doubled with no increase in the constant current supply. The new technique, involving a serial connection, ensures that all of the supply current becomes available for the means current in pulses of each polarity separately instead of the two polarities together.
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