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Here are some puzzles which have arisen concerning vintage calculators

Can you provide any further information?


Although the years of the Vintage Electronic Calculator, the 1960s and 1970s, are not so long ago, it is sometimes very difficult to find information about some calculators and their manufacturers.

Below are some things which have been puzzling us. If you have any information about these items please contact us.

Below that are Queries from Readers of this Site.



Century Mk IV

Was Century Mk IV the name of a company ?
Here are three examples of several calculators marked "Century Mark IV":


Century Mk IV, type 1

9v (PP3).

8 digits, red LED.


80 x 144 x 22 mm / 3.1 x 5.7 x 0.9".

"Century Mark IV
New York"

Century Mk IV

Century Mk IV, type 2

9v (PP3).

8 digits, red LED.


88 x 147 x 26 mm / 3.5 x 5.8 x 1.0".

Made in Canada.


The label on the back says "Special Offer Headquarters 6775 West 174th St., Tinley Park, Illinois 60477".

Bowmar Century Mark IV

Bowmar Century Mark IV
(model number 90512 on the label on the back)

4.5v (3x AA rechargeable).

8 digits, red LED.


Size: 78 x 149 x 34 mm / 3.1 x 5.9 x 1.3".

Made in U.S.A.
Acton, Mass. 01720

This is obviously a Bowmar calculator, but was it labelled "Century Mark IV" for sale by another company.

Answer 1: Frank Fröhn reports that calculators with the "Century Mark IV" logo were made for and exclusively distributed by Gulf Oil Mail Order.
Answer 2: Erico Mendonça reports that the the address at Tinley Park, Illinois, U.S.A., given on the label on one of the calculators, see above, was rented to "Illiana Data Processing" and  "Penny Saver" (a shopper publication) after 1967, so it was probably marketed by one of these.

Rockwell Anita 1216

Which company made it ?

Rockwell Anita 1216

Rockwell Anita 1216

Display is 12 digits, amber gas discharge.

4-function, %, memory

Size: 256 x 193  x 70 mm / 10.1 x 7.6 x 2.75"


The integrated circuits: Electronic Arrays EA 7022, EA 7023 here dated 1973.


The label on the rear shows:
"Rockwell International. Sumlock Anita Ltd. Uxbridge England"
"Made in U.S.A"
The circuit board was made by Cherry.

This calculator is very unusual because Rockwell was one of the largest manufacturers of calculator integrated circuits and used them in its calculators. Yet this calculator uses integrated circuits from one of its rivals, Electronic Arrays. This could be due the machine having been designed and sub-contracted by Sumlock-Anita Electronics Ltd. before the company was bought by Rockwell in 1973.

Answer: Frank Fröhn reports that this calculator is similar to the Summit S1219, from Summit International Corp, Salt Lake City, Utah, U.S.A. It could well have been that Summit was contracted by Sumlock-Anita to supply this model, and it was continued for some time after Rockwell bought Sumlock-Anita.

Calculator Manufacturers

Many hand-held calculators made in Japan or Hong Kong have circuit boards or keyboards stamped "GICO", as shown on the left on a Commodore 784D calculator. This probably refers to a company.
Do you know what the letters GICO stand for, or have any information about the company ?
If you know please contact us.

The number series in the second line appears to be a date code in the traditional Japanese system. This is year.month.day, where the year is that of the Showa era (i.e. the years of the reign of emperor Hirohito), where:

Showa 45 is 1970
Showa 46 is 1971
Showa 47 is 1972
Showa 48 is 1973
Showa 49 is 1974
Showa 50 is 1975
Showa 51 is 1976
Showa 52 is 1977
Showa 53 is 1978
Showa 54 is 1979

Calculator Integrated Circuit Manufacturers


A lot of companies which made calculator integrated circuits no longer exist. Some had logos which are now unfamiliar.
Can you confirm the following logos:

Summit 3114

Summit 3114

This has 3 ICs labelled IST 7061, IST 7062A, IST 7063, having a logo of a Y in a circle - Does anyone know the manufacturer of the ICs ?  They are date coded to mid-1972.

Click on the picture to go to the desk calculator section for more details and more, pictures.


If you have any information about these items please contact us.

Vintage Calculators

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