Not 100% sure yet but I have an E4445A spectrum analyzer with a dead battery, it thinks it is an E4440A, has lost all options, and can't even run self cal because it doesn't know it has a preamp in it.? Per-incident service charge is $7500 with Keysight.? I haven't determined if all of this information was retained by the battery, but it appears this may be the case.
