Classic Calculator dont turns on with battery

[grsbanks]

(12-06-2020 09:37 AM)CY-CL Wrote:  The calculator don't turn on with battery inside and no charger is plugged.

In that case there are two common faults.

1) The battery is simply dead. If you've not rebuilt a battery pack then this is almost guaranteed. The Ni-Cad cells are 45 years old now so there's little chance they will work.

2) When you plug the charger in, it pushes on a brass tongue and this opens a contact. Remove the charger and the tongue goes back into its original place and makes the contact again. This contact could be dirty.