DATAMATH CALCULATOR MUSEUM |
Unitrex 1000 - a.k.a. Far East Generic Design I
Date of introduction: | 1977 | Display technology: | LED-stick |
New price: | Display size: | 8 | |
Size: | 5.2" x 2.8" x 0.9" 132 x 70 x 23 mm3 |
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Weight: | 2.5 ounces, 70 grams | Serial No: | VP 587599 |
Batteries: | 9V | Date of manufacture: | mth 09 year 1977 |
AC-Adapter: | Origin of manufacture: | Hong Kong | |
Precision: | 8 | Integrated circuits: | MOS MPS7560 |
Memories: | 1 | ||
Program steps: | Courtesy of: | Joerg Woerner |
You are familiar with this Unitrex 1000 calculator?
You
are right, this calculator - and the siblings named Academy, academy memory, Alltronic HK 9805,
Bohsei 3000,
Bowmar, Cetina ET, Comico 1000, GPM 15,
Gracia, Harvard Student H-303, Janon 3000,
King Sonic 3000, MBO 3000, Nikjan,
Nobility 3000, Noris 3000, Planar Memory,
Realtronic, Seneca 1000 and Tronica 3000 - are a nearly perfect copy of the TI-1250.
This Unitrex 1000 caught out attention with its unusual [X/Y] key instead the
more common [CS] key.
Dismantling
this Unitrex 1000 calculator manufactured in September 1977 in Hong Kong reveals a very
cost effective design using a single-sided printed circuit board (PCB) centered
around an MPS7560 single-chip calculator circuit manufactured by MOS
Technologies connected to an 8-digit LED display, a keyboard assembly and
powered by a 9 Volts alkaline batteries.
The
unexpected use of the MPS7560 instead the
TMS0972 with the featured Unitrex 1000 calculator explains obviously the
[X/Y] key, we knew already from the Commodore Model 797M based on the same chip
an [EX] key to swap the X- and Y-Registers to simplify some chain calculations.
All other features of the MPS7560 seem to be similar to the TMS0972, we noticed
with the HR-1001 a 9-digit LED display with just 8 positions populated..
Within the Datamath Calculator Museum we refer this calculator as Far East Generic
Design I, probably the cheapest calculator of the 1970s. Don't miss the Design
II and Design III.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, February 14, 2023. No reprints without written permission.