HP-25 - what could be wrong, simple question

[albertofenini]

HI Bernard
First of all thanks for your reply
So this behavior doesn’t necessarily mean that the Ram is defective ?
It could also be the ACT chip ?
Since we were able to do math operations we assumed that the ACT was working
How can we check if the pin 11 is connected with the RAM ?
Could it be a bad trace or you mean is disconnected inside the ACT CHIP ?
This kind of unit could it be restored with a lot of yours ?
Thanks again!!