Rohde and Schwarz FS3 Spectrum Analyzer Power Up Failure

[DrTom]

I have a RS FS3. It was coming on when plugged in but would not when "on battery". I bought a new battery but it wouldn't come on at all. I've inspected the PCB but don't see anything obviously burnt. Anyone have a schematic or suggestion on how to get it working?
Thanks...Tom

[m k]

Maybe it's a simple battery contact problem.

My guess is that the problem is not far from battery.
Should be quite easy to follow the trace with DMM.

[pdenisowski]

Sorry to ask, but is the battery charging when it's plugged in?  Does the FSH show the battery as charged?  If you bought the battery from us, it's not charged when it's delivered.

If you bought it from a 3rd party:  I've seen some permanently dead FSH3/6 batteries: like all rechargeable batteries, they have a finite lifespan and the FSH3/6 is an older platform (about 15 years since we stopped making them).

At a minimum, I would use a DMM to check that it is holding a charge in the open state (i.e. battery unconnected to anything)