Description
The Addo Model 9 is a vintage mechanical adding machine produced by Aktiebolaget Addo in Malmö, Sweden, between 1927 and 1936. It was designed for performing addition and subtraction operations, with a full-keyboard layout tailored for Sterling currency (pounds, shillings, and pence).
🧮 Key Features
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Currency Format: The Model 9 was configured for the British Sterling system, accommodating amounts up to £999,999/19/11 (pounds, shillings, and pence) .
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Full-Keyboard Layout: It featured a comprehensive keyboard with keys for digits, shillings, pence, and farthings (quarter-pence), facilitating detailed financial calculations.
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Function Keys: The machine included several function keys such as Repeat, Clear, Non-add, Subtract Lock, Subtract, Sub-total, and Total, enhancing its versatility for various arithmetic tasks
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Design and Construction: The Model 9 was known for its robust construction and distinctive design, often encased in a polished black Trolit cover with a gold Addo logo .
🛠️ Historical Context
Addo, founded by Hugo Agrell in 1918, was a prominent Swedish manufacturer of mechanical calculators. The Model 9, along with its contemporaries like Models 6, 7, 8, and 10, was introduced in 1927 and remained in production until 1936, when it was succeeded by the Model X series .
