This collection shows models designed between 1931 and 1960, pointing the constant improvements made during that period. The simplest model has limited capabilities, while the most complex BTZG machine is able to make all operations automatically, with four working registers, and options like square root calculations. To my mind, it is particularly interesting to keep up with the progress of every model, by following the natural sequence of this portfolio. Only basic information, allowing to recognize different models, are presented here.
The collector’s corner
Choose in the left side navigation menu the model for which you want to consult informations.
By clicking onto the photos, you can see them in their original size.
Collectors who acquire machines often have difficulties to identify clearly what model it is.
Identification of models
Sometimes, the label that indicates the serial number, also gives the name of the model. More often, there is no indication. By clicking on the button, you can access several cross-reference tables, which allow an easy identification. These tables are based on the choice of a few discriminating easily identifiable features.