I have recently acquired a 3458A which incorporates a Schaffner FN9223-3-06 mains filter. The 3458A has a build date of approx 2005 and the Schaffner filter has a date code of 0432.
I am wondering if these later Schaffner filters have the same dramatic failure mode exhibited by their earlier models and whether it should be replaced. I am reluctant to replace it if it is not necessary due to it being riveted into the chassis.
