| 摘要 |
A system is provided for energizing the meter accounting circuit. The postage meter is of the type having a mechanism for printing postage and accounting circuits which account for postage printed by the printing mechanism. A secure housing means encloses and protects the mechanism, the accounting circuit and the system for energizing the accounting circuit. A source of operating potential external to the secure housing is also provided. A transformer is connected with its primary winding coupled to the source of operating potential and to the first and second electrode current path of a three terminal switching device to control the current flow through said primary winding. A timer circuit is provided and includes a first terminal which oscillates at a frequency depending on the voltage applied to the timer circuit second terminal. The timer circuit first terminal is coupled to the control electrode of the three terminal control device. A feedback circuit is coupled between the transformer secondary winding and the timer circuit second terminal for varying the voltage applied to said timer circuit second terminal depending upon the voltage level developed in said transformer secondary winding.
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