The Olympia OP644 is a programmable calculator with 12 digits precision and algebraic logic. It has 54 keys, and an LCD (liquid crystal) display. The power source is 2x3V cell + sealed battery. The calculator was manufactured in Japan. Note: Casio PB-300
Facts at a glance:
|Power Source||2x3V cell + sealed battery|
If you have an Olympia OP644 that is no longer working, you can first try replacing the 2x3V cell + sealed battery batteries. If that doesn't solve the problem, then you can consider replacing the calculator with a modern equivalent.
We suggest the following current model as a replacement: