HP-34C Won’t Power Up

[stevenme]

My 34c no longer powers up, no display at all. It was working and I think I can narrow it down to two (stupid) things that I did just before it stopped working.

1. I noticed the traces on the circuit board were worn where the connector plugs in and I was attempting to use the charger to power the 34c without the battery pack installed.
2. While installing a rebuilt battery pack I may have allowed the voltage to the 34c to be reversed momentarily
   

I know a bit about hardware so I know either could have caused damage. I was wondering if incorrect polarity or a voltage spike could damage the 34c? If so is this something that can be fixed with off the shelf components and a soldering iron? Thanks,

Steve