Classic Calculator dont turns on with battery

[CY-CL]

xxxxxx

[AndiGer]

If you plug in the charger it won't turn on from the battery. The contact in the charger plug inside the calculator is separated by the charger.

[CY-CL]

The calculator don't turn on with battery inside and no charger is plugged.

[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.

[AndiGer]

Check with an ohmmeter with no battery installed you get contact
a) from lower battery contact (plus) to left and right charger plug pins
b) from upper battery contact (minus) to center charger plug pin
If you don't get mentioned contacts you have to examine the reason.

If contact a) is missing you can try to get it work from outside without opening the calculator. Try to clean (or even bend a little bit) the gold plate that bridges the both outer contacts.