I have a Agilent 3458A that needs a Cal Ram battery, however, I need to find out the manufacturing date. The SN is 2823A18621 and the is no date on the back of the unit. According to the Keysight instructions, "For units shipped between June 2008 and September 2008 the errors are caused by bad SRAM and the entire A5 assembly must be replaced." Thank you.
Terry ONeill
Terry,
The controller board of this vintage (date code) can probably be repaired by yourself. To make sure that the controller board is still the old one, just open the top cover, and look if there are DALLAS nvRAMs inside.
Then you need GPIB connectivity to save the calibration data, an appropriate programmer, and these 3 Dallas nvRAMs, which still are available from distributors. Then of course you need soldering/desoldering tools.
If you have these capabilities , then more details are available on other ,well known' forums. Alternatively, I may copy this info here.
Frank