With the help of Ingancio Sánchez, we have begun analyzing the failure modes of the HP41c, and we have been developing repair techniques for most of them. In the next articles, we will present the failure modes and the possible techniques in each case.
Corroded battery terminals
Corroded main circuit
overdone lower screw posts
overdone upper screw posts
Broken lower screw posts
Broken upper screw posts
Corroded or broken zebra connector
Broken screw supports on the back side or the case (usually the upper ones)
Missing back port
Missing side port
Corroded spring for battery holder
Broken or missing battery holder
In full nuts, overdone nuts to keep circuit pressure - an alternative to nuts.
Broken plastic window
In next instances, we will go one by one with each of the chapters. Who knows, it may end up as a book!