Calculators sold by Sumlock and made by other companies
Logatronic Visible Record Computer

Logatronic Visible Record Computer

The Logatronic programmable mini-computer for invoicing was developed in the mid-1960s by the Nixdorf Computer company.

A brochure gives the following information:

Logatronic Visible Record Computer

Wanderer logatronic

The WANDERER logatronic is a computer for invoicing, statistical and accounting work. As a modern machine for offices and organizations it possesses all the essential features of electronic accounting systems. Advanced in conception, it points the way to new methods of office automation—methods which have so far been the prerogative of machines costing a lot more. With this computer the complex requirements of commercial, technical and scientific calculations are fulfilled.

With its internal programming facilities, the WANDERER logatronic can be tailored to the needs of any type and size of business. Its capacity matches whatever task it is called upon to perform. It fits readily into every type of system and thus meets the precondition for direct, up-to-the minute data acquisition and processing. The advanced plug-in techniques used permit extensions and additions at any time to cope with changed organization. The programme store — which is the control centre of the computer — can receive and handle a number of independent programmes. Printed circuits, silicon transistors and complete elimination of relays and other moving parts subject to wear give the WANDERER logatronic practically unlimited life.

The "memory" of the WANDERER logatronic consists of the required number — 4, 7, 11, 25, 60 or 120 — of magnetic core stores. Five internal working stores form part of the basic equipment of every model.

The WANDERER logatronic makes logical decisions. It also compares values independently and draws the appropriate conclusions for the further progressing of the work.

The error protection programming (ISP system) represents a large measure of protection from operating errors and ensures that the proper operating sequence is followed. A check digit comparison tests the values put in via the keyboard and checks the mutual dependence of terms of different kinds.

The WANDERER logatronic is provided with alpha-numerical calling back of constants. Selection of programmes, stores and constants is made via the keyboard.

Voltage fluctuations and the action of switching the machine on and off do not affect the stored data.

A wide range of models and peripheral equipment can be supplied to provide the right facilities for any application. Our experienced systems engineers are available to advise if required. All machines are backed by an extensive, first-class service system.


A close-up of the calculator input unit.


The drawer has been opened to show the electronic circuits.


Central unit with electronic computer, data stores and programme stores Input keyboard and electric typewriter Printed circuits and modem electronic circuitry

Data stores

Equipped, as required, with 4 to 120 balancing magnetic core stores each with a capacity of 14 digits Additional working stores for internal calculating operations "SHIFT" arrangement for arithmetic shift, capacity splitting and partial reading of values Programmable rounding up and rounding down Automatic point setting

Computing Unit

Silicon transistor digital computer performing addition, subtraction, multiplication and division Evaluation of powers of numbers, root extraction and formula evaluation are programmable Logical decisions Input capacity 14 digits Product capacity 28 digits Index register

Programme memory

250, 500, 1000, 2000, 3000 and 4000 program instructions Instructions built up on the "multi-address" principle Internal programming Alphanumerical storage of constant and variable terms   Error protection programming (ISP system)

Input Unit

International keyboard with overlapping numeral input Freely programmable function keys Keys for automatic position shift Store, programme and constant selection, item addition

Output Unit

Electric type-head machine of special design Platen width 13 in. (33 cm) for 131 strokes Type width 1/10 in. (2.54 mm) Printing rate 930 characters per minute (15 per sec.) Electronic positioning of type-head

Additional features

5 to 8 channel tape punch for alphanumerical data collection
Automatic front feed
Pin wheel platten


Desk of wood and steel construction, plastic surface to desk top   Dimensions 55 X 28 X 30 in. (140 X 70 X 75cm).


Tel 01-493 1331 & 1532



The Logatronic appears to have been developed further to become the Nixdorf Visible Record Computer.
For information about Heinz Nixdorf, the company, and its computers see

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Text & photographs copyright © 2002 - 2023 Nigel Tout, except where noted otherwise.