My HP-15C revives......

[Johnny Shek]

(10-04-2018 08:43 AM)grsbanks Wrote:  You might not have had to wait a couple of days if you'd removed the new batteries, shorted out the battery contacts in the 15C, pressed a few buttons for a while and re-inserted the batteries

I replaced batteries for so many times in the last 33 years. However, this is the first time that I encountered this situation. I once thought that some components inside the calculator might have malfunctioned considering its age.