Patent References 3800207 Power monitoring and load shedding system Binary digital pager having an eight function code read-out Pager with escalating audio alert signal level Pager with visible display indicating status of memory Multiaddress pager with a call storage and priority paging option Low battery voltage indicator circuit for a metal detector Wireless telephone apparatus with protection against power loss Pager with automatically illuminated display Reduced power consumption low battery alert device Patent #: 4660027 InventorApplicationNo. 06/924375 filed on 10/29/1986US Classes:340/7.37, Control based upon available power340/636.1, Battery340/636.15, By voltage340/7.58, Alert455/343.5Battery saving based on detected power source levelExaminersPrimary: Caldwell, Sr., John W.Assistant: Holloway, III, Edwin C. Attorney, Agent or FirmInternational ClassesG08B 3/10 (20060101)G08B 3/00 (20060101) G08B 29/18 (20060101) G08B 29/00 (20060101) H04B 1/16 (20060101) H04Q 7/18 (20060101) AbstractIn a battery powered radio paging receiver, a battery saving method extends battery life and prevents the loss of messages stored in volatile random access memory. Upon receipt of a message, a plurality of alerting devices (vibrators, LCD back-lights, LED's and audio alert tone generators) are sequentially activated. Before each device is activated, however, the battery voltage is checked to determine if sufficient charge remains to power the alerting device without dropping the battery voltage below the minimum requirement for retaining information in the memory. If an alerting device is activated, the battery voltage is repeatedly checked and if it drops below a threshold level, the device is deactivated. If the alerting device is an escalating volume audio alert tone generator and the battery voltage is below a threshold voltage, the volume of the generator is restricted to its lower volume range. The received message is also checked to determine if it has a priority status. If the message is a priority message, all alerting devices are activated, regardless of the battery voltage. | |