HP8594A resets when trying to backup Correction Constants

[MARIOSSV0CL]

Hi

I have HP8594A spectrum analyzer and i am trying to back up Correction Contansts  but analyzer appears to reset when Edit Fflatness is initiated.
Following service manuals instructions, using -37 Hz password, "srvc" appears on the left down corner, next if i push "VERIFY TIMEBASE" the Timebase Number appears and everything seems to going well but if i push "SERVICE CAL" to retrive Flatness Data a warning message appears "FACTORY CAL DATA CAN BE LOST".

If i continue pressing  "EDIT FLATNESS" the analyzer reset and retern to normal use contition.

S.N: 3108U00130

Rev: 17.12.90

Can you help me please??

Thank you in advance.

Marios

[radioengineer]

Hi,
I came across this questuion having run in the same problem after a battery replacement.
In my service manual it says to use FREQUENCY -2001 Hz code for this procedure.
But reset appears also, if I tried to use "EDIT FLATNESS".

I've found this service note 8594-02 on hpwiki.org:

https://hpwiki.org/_media/service_notes:8594a-02.pdf

Following the instructions let me re-enter my Frequency Response Correction Constants with the EDIT FLATNESS function.

Regards, Rolf