| 摘要 |
A disposable portable radiotelephone subscriber unit (101) comprises a power supply (255), a transceiver (205, 207) and a controller (215). The power supply (255) has stored therein a predetermined measure of power capacity (281). The transceiver (205, 207) is permitted to operate for a predetermined period of time (405) responsive to the predetermined measure of the power capacity (281). The controller (215) monitors a rate of depletion of the predetermined measure of the power capacity (281). The controller (215) permits operation of the transceiver (205, 207) when the power capacity (281) is being depleted at a desirable rate, thereby decreasing the predetermined period of time (405) that the transceiver (205, 207) is permitted to operate. The controller (215) prevents operation of the transceiver (205, 207) when the power capacity (281) is being depleted at an undesirable rate, thereby prolonging the predetermined period of time (405) that the transceiver (205, 207) is permitted to operate. Alternatively, the power supply (255) may be a memory unit (259) and the power capacity (281) may be calling time (279) or a future electronic date (275). |
