Faber-Castell TRX

Date of introduction:  1974 Display technology:  LED
New price:   Display size:  8 
Size:  2.3" x 6.8" x 0.6"    
Weight:  2.5 ounces Serial No:  
Batteries:  2*AAA Date of manufacture:  
AC-Adapter:   Origin of manufacture:  Germany
Precision:  8 Integrated circuits:  
Memories:  1    
Program steps:   Courtesy of:  Peter Muckermann († April 21, 2021)

A.W. Faber-Castell, a German manufacturer of slide rules, introduced in the year 1973 the „TR1 Calculator Slide Rule“. One side of the housing featured an electronic calculator and the other side a traditional slide rule. Although the idea was innovative that time the success on the calculator market was very limited.Compared to the huge line of calculators by German competitor ARISTO starting with the M27 only 4 Faber-Castell calculators are known:


TR1 Memory, x2 and 1/x


TR2 Full Memory, x2, sqr(x), % and 1/x


TR3 Full Scientific including logarithmic and trigonometric functions


TRX Missing the slide rule on the back

horizontal rule

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© Joerg Woerner, May 3, 2002. No reprints without written permission.