Citizen 820R
The Citizen 820R is an arithmetic calculator with 8 digits precision and algebraic logic. It has 7 functions, 22 keys, and a VFD (vacuum fluorescent) display. The power source is 4xAA batteries.
Facts at a glance:
| Feature | Value |
|---|---|
| Type | Arithmetic |
| Functions | 7 |
| Keys | 22 |
| Precision | 8 |
| Logic | Algebraic |
| Display type | VFD |
| Length | 151mm |
| Width | 87mm |
| Thickness | 34mm |
| Power Source | 4xAA batteries |
| Year introduced | 1974 |
| Year discontinued | 1976 |
Replacements:
If you have a Citizen 820R that is no longer working, you can first try replacing the 4xAA batteries. If that doesn't solve the problem, then you can consider replacing the calculator with a modern equivalent.
We suggest the following current models as possible replacements: