Thanks Yves, I will put in a new battery and see how it goes. I am thinking of a rechargeable Li-Ion mounted on the rear panel with the wiring going to the board,
I am in the process of repairing a HP8591A spectrum analyser which seems to have a control fault. Apparently the previous owner tried to replace the control board battery, and now the instrument has a control problem. I can get it to work by going into the config menu and resetting the config, when the green Preset button is pressed, it goes into a and less control loop that causes the display to 'jitter'. Can anyone point me to the CLIP and troubleshooting manual?
