New Stuff
Author
Links
Guest book
Web-log
Bric-a-brac
Calculators
Components
Ephemera
Events
Glossary
History
Hit or Miss
Radios
Transport
Valves
Wanted
Metal Puzzles
Clocks
Calculators: Handheld: Brother 408AZ
|
|
|
Size (approx): |
85mm
x 145mm x 20mm(max) (w,h,d) |
|
Power: |
6V DC, 4 x AA size batteries. It accepts an adapter/charger (use model 4086A, 6V DC 0.4W) through a socket on the top about 3cm from the right edge. The battery compartment is rather odd on that the lower edge (which is keyed to go in only one way) pulls off to reveal two tubes down either side to feed in the batteries. Direction guides are embossed on the rear to help you correctly load the calculator. | ||
| Case: | Main case is two piece gloss white plastic. The front section is a gloss black plastic and sits with its own raised border. It is printed gold (for the brand) and silver (for the model, key and switch labels) with grey borders. The small keys are medium travel with a soft click. The green plastic display filter is inset and gently tilted. | ||
| Display: | 8 digit green VFD display with ninth digit for negative and error indication. | ||
| Features: | Standard four functions, percentages, square root, sign change and and pi. | ||
| Age: | 1976 | ||
| Manufacturer: | Brother Industries Ltd., made in Japan, serial number J5069663. | ||
|
Comments:
|
Quality feeling, slim and sturdy calculator with a large bright display and torch-like battery loading. Basic logic is let down by input overflow, lack of general recovery and negative square roots. The original case is soft black plastic with open top and half-moon cut-outs front and rear. Some doubt on the component dates as the Itron appears to be a Japanese date code (1=1976, 2=1977 etc.) This would tie in with the mid 1975 IC date code. |
| Components: |
1 x cpu: NEC
µPD940C H5429M 28 pin DIL, 0.6" width black plastic |
| Boards: | The keyboard assembly (BP-2152-1) is fixed to the front with three screws, whilst the T-shaped main cpu board (BP-2151-2) is lose in the case, held by some guide rails and by the adapter socket. The two are joined by ten stiff wires insulated with some tape. |
| Construction: | Remove the battery cover and the two screws visible at the back. Pop the side lugs by gently squeezing in the edge of the rear section. Then top edge is very carefully pushed upwards - the most difficult bit. Hinge the case apart from the bottom edge. You will see that the font section has sufficient holes for another seven keys or switched. |
| Logic comments: | (CI) cancels an incorrect numerical entry and (C) clears the calculator |
| There is automatic constant on all four functions | |
| Input overflow is not suppressed, inputting a ninth digit causes an overflow which is recoverable using (CI) | |
| Negative numbers are shown with a "-" in the immediate left hand digit, travelling into the ninth to allow full eight digit negative numbers | |
| Divide by zero shows zero and "E" in the far left (ninth) digit and is not recoverable | |
| Overflow is shown by the result and "C" ("E" if negative) in the far left (ninth) digit and is not recoverable | |
| Negative square root are allowed and result in a negative number | |
| The change sign function can be used in mid number entry but not before | |
| No major bugs found. |
