| 摘要 |
A portable transceiver has a battery saving feature which includes a timer, circuit which automatically cuts off the power supply to the receiver and transmitter for relatively long intervals and periodically turns on the power supply for relatively short intevals to check for transmission or receiver signals. If such signals are detected, the power supply continues to supply powers to the receiver and transmitter for the duration of the signals and for a short period thereafter. The transceiver also includes a batter voltage detection circuit which will cut off the battery power supply if the battery has discharge to a predetermined level , and which can be overridden in any emergency. The power supply is conveniently controlled by a pass device which must receive "operate" signals from both the timer circuit and the battery voltage detection circuit.
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