Hi There!
My beloved Agilent 54622D Mixed Signal Scope recently complained about Low Battery when switching on. Since all settings were defaulted when switching on (Labels, etc...) I gave it a try to replace the battery.
I checked the net and found some posts that the battery can be replaced by a new one even without backing the unit up during replacement.
It's a Panasonic CR2354 that is soldered to the system board. For replacing you have to take out the complete system board. Also removing the heavy heat sink / Shielding of the two analog frontends (
Service manual: Caution: USE AN EXTERNAL FAN TO AVOID OVERHEATING COMPONENTS !
If you operate the oscilloscope with the cabinet removed, you must use an
external fan to blow air across the system board. This external air flow is
necessary to cool the heat sinks on the system board. Otherwise, damage to
the components can occur.) until you can desolder the battery from the bottom surface. There also was a crusty 3M sticker underneath as well. Yuk! The 3V battery was dead down to about 0.4V.
Surely, I did the work on a proper ESD safe workbench with writst strap and proper grounding. After replacing and reassembly I switch on the unit and the device now is just running the fan and lighting up all LEDs on the front panel. No further booting.
I checked all cables and marked voltages on the system board. They are ok.
Is there somebody out there that experienced similar issue? How is the support from Agilent / Keysight for such a vintage equipment? Any idea how to bootstrap that puppy?
Best regards from Germany
Jan