New Stuff
Author
Links
Guest book
Web-log
Bric-a-brac
Calculators
Components
Ephemera
Events
Glossary
History
Hit or Miss
Radios
Transport
Vales
Wanted
Metal Puzzles
Articles
Clocks
Calculators: Handheld: Casio H-3
|
|
|
| Size (approx): |
85mm x
140mm x 22mm (max) (w,h,d) |
| Power: | 3V DC using 2 x AA size batteries. It accepts an adaptor (DC 3V 0.36W, AD-2S) through a socket on the top side to the far right. The on/off switch is on the left hand side in line with the "H-3" text. |
| Case: | Two piece case in black and (originally) white smooth plastic, which is slightly wedged shaped. The front is dominated by two large brushed aluminium panels. The upper panel has black and red printing for the brand and model number and is also softly coloured a very light yellow. The lower panel surrounds the keyboard and has black printed text for the switch labels. A neutral, slightly proud but flat display filter gives a good bright image. The keys are typical Casio, squishy but work well. |
| Display: | 12 digit blue VFD with an extra symbol cluster for error, negative and memory indicators. |
| Features: | Standard four functions with backspace, sign change, delta percent, percent, square root and four function memory. Switched floating and fixed decimal points. |
| Age: | estimate 1984 |
| Manufacturer: | Casio Computer Co., Ltd., made in Japan. Made in Japan. Serial number 5B101A printed on the inside of the battery compartment cover. |
| Comments: | Whilst this looks like a typical Casio calculator from the period, the edges are a little sharper than normal and the functions and display are more like a desk-top machine. Still, nice bright display, useful functions, 12 digits and solid logic make this rare model quite likeable. |
| Components: | 1 x cpu; Hitachi HD38401A 4L45
(poss. 1984 date code), 36
pin DIL, 0.6" width 1 x 12 digit VFD; single glass tube flat faced: FIPI3G5 2 x transistor 10 x diodes 8 x capacitors 5 x resistors 1 x transformer; TDK TC-32 4Y |
| Boards: | The main cpu board (G182-1A) sits loose on the front of the calculator and is joined to the main keyboard assembly via 19 strong wires. The latter is fixed to the font with six screws. There is a very large copper plate mounted on the reverse of the cpu board underneath the main IC. |
| Construction: | Remove the single screw from inside the battery compartment. This does absolutely nothing as the case is held together by internal lugs. Carefully pop the lugs on each side by pushing in the white rear panel with a fingernail. Very easy to cause damage so if in doubt don't do it. The rear then lifts off. |
| Logic comments: | (C) clears the last number entered whilst (AC) clears the whole calculator |
| Input overflow is not suppressed, inputting a thirteenth digit results in the display of "E" in the far left symbol cluster which is recoverable using (>) | |
| Negative numbers are indicated by a minus sign in the far left symbol cluster thereby allowing eight digit negative numbers | |
| There is automatic constant on multiply and divide only | |
| The change sign function can be used in mid entry | |
| Divide by zero shows zero and an "E" in the far left symbol cluster and is not recoverable | |
| Overflow shows the result and "E" in the far left symbol cluster and is recoverable using (C) or (>) | |
| Negative square roots are not allowed but show the result with "E" in the far left symbol cluster and is recoverable (to a negative number) using (C) or (>) | |
| Memory store is indicated by an "M" in the far left symbol cluster | |
| A switch changes between floating [F}, round down [cut] or round [5/4] modes | |
| A second switch changes the modes to fixed 4,2 or 0 decimal places |
|
|
The scan of the main board clearly shows the ID
marks, place labels for components.
You can also see the symbol cluster on the left of the 12-digit display - very much like a desk-top calculator. The very long Hitachi IC has a large copper shielding plate on the reverse side of this board. |
|
