RFT minirex 73

Date of introduction:   Display technology:  LED-modules
New price:   Display size:  8
Size:  5.5" x 3.2" x 1.3"    
Weight:  11 ounces Serial No:  009903
Batteries:  4*NiCd  Date of manufacture:  year 1973
AC-Adapter:   Origin of manufacture:  GDR
Precision:  8 Integrated circuits:  S2144 or MK5020A
Program steps:   Courtesy of:  Gerhard Wenzel

The minirex 73 manufactured in the GDR (German Democratic Republic) end of the year 1975 looks similar to other calculators based on TI's calculator chips. Compare it e.g. with the famous Bowmar 901B

rft75_2.jpg (31657 Byte)The minirex 73 uses a charging craddle as a comfortable stand during operation and to charge the four internal NiCd-batteries (picture shows minirex 75). The calculator was later replaced with the minirex 74 and minirex 75.

PCB737475.jpg (156216 Byte)From the technical point the inside of the minirex 73 is from higher interest than the awful appearance. The picture on the right shows the minirex 73, 74 and 75 from left to the right. The earliest calculator uses a US calculator chip, the next a GDR developed one-to-one copy of a TI chip and the latest product the original

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Joerg Woerner, December 5, 2001. No reprints without written permission.