HP15C displays gibberish. Is it broken?

[sebi]

(10-06-2020 04:38 PM)lyuka Wrote:  It was not the axial lead inductor that was hot, but the dip tantalum capacitor at the power input.

Can you show me the dip tantalum capacitor you are talking of on the picture: is it the blue capacitor-looking component on the left of the green axial lead inductor?

(10-06-2020 04:38 PM)lyuka Wrote:  After that, it is presumed that the short-circuited state became open and the operation was restored because the fuse in the tantalum capacitor was blown or the solid tantalum was completely burned down.

Sorry but I didn't get what you explained: A capacitor is mounted in parallel whereas a fuse is mounted in series, right? Didn't the tantalum capacitor acted more like a diode in parallel, thus creating a short-circuit when being reversed-powered and protecting the processor? Blowing a fuse in that tantalum capacitor would have resulted in no more short-circuit thus no more protection for the processor, right?