APF MARK 21
The APF MARK 21 is an arithmetic calculator with 8 digits precision and algebraic logic. It has 6 functions, 24 keys, and a VFD (vacuum fluorescent) display. The power source is Sealed battery pack.
Facts at a glance:
| Feature | Value |
|---|---|
| Type | Arithmetic |
| Functions | 6 |
| Keys | 24 |
| Precision | 8 |
| Logic | Algebraic |
| Display type | VFD |
| Length | 159mm |
| Width | 76mm |
| Power Source | Sealed battery pack |
| Year introduced | 1976 |
Replacements:
If you have an APF MARK 21 that is no longer working, you can consider replacing the calculator with a modern equivalent.
We suggest the following current models as possible replacements: