Calculator Marketed by
Sumlock & Tabdown
Sumlock & Tabdown Ltd.
This was one of a number of Sumlock local offices around Britain which were involved in marketing Sumlock-Anita calculators. When Rockwell exited the calculator market in 1976 the ex-Sumlock-Anita sales offices and service offices were then offered as franchises to those who worked in them. Some of the sales offices incorporated 'Sumlock' in their new company names and sourced electronic calculators from elsewhere which initially carried the new Sumlock name.
Sumlock & Tabdown Ltd. of Bristol appears to have been one of these new companies but there is little information about it. However, here is a calculator labeled for the company here:
Sumlock Tabdown
Sumlock Tabdown
The display is 12 digits green VFD (Vacuum-Fluorescent Display).
The calculator is powered by AC.
Main integrated circuit is Mitsubishi M58623-23P , with 3xToshiba TM4358P here date coded 7-D (that is 1977, weeks 8-9).
Four-function, square root, memory.
194 mm x 240 mm x 65 mm (7.6" x 9.4" x 2.6").
Made in Japan.
Sumlock & Tabdown Ltd., 4 Unity Street, Bristol.
There is little information about Sumlock Tabdown and this is the only calculator known to be labeled for the company. This calculator is identical to the Decimo VATMAN OFFICE DELUXE calculator illustrated on the associated Vintage British Calculators website.
It is unknown whether the calculator originally had a proper nameplate on the front. It does carry a paper label with "SALES & SERVICE, SUMLOCK & TABDOWN LTD., 4 UNITY STREET, BRISTOL, BS1 5HH, TEL:0272-276685"
The label on the rear with "SUMLOCK TABDOWN LTD., BRISTOL" and "MADE IN JAPAN"
With the front cover removed showing the power supply, vacuum-fluorescent display and keyboard.
Close up of the electronics with the main integrated circuit being the Mitsubishi M58623-23P towards the bottom of the photograph. The other three integrated circuits are Toshiba TM4358P.
Continuing Companies
Text & photographs copyright © 2002 - 2023 Nigel Tout, except where noted otherwise.