These settings are at "defaults", but can be changed.
Battery voltage is a MIN level before the radio decides to power down.
Setting it at some middle ground will prevent the radio from being totally out of power before this happens, but not so high as it thinks it needs to shut down but still has enough power to run for an hour two more.
If you have the manual, I think this is explained.
We have a PDF manual for the PRO97, and it's on our On Line Help website
Using the PDF you can search for keywords and find where it is detailed.
Under the settings tab there is a block for setting your back light, contrast, brightness, and battery voltage. The one I do not understand is the battery voltage and what this setting is for. Could you explain this setting for me and suggest its setting level. I have a RadioShack Pro 97.
Michael J. Adams
Water/Wastewater Services Division
General Maintenance Division
City of Bartlett, TN.