Calculator Puzzle Corner




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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. *Calculators*

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

Century Mk IV

9v (PP3).

8 digits, red LED.

4-functions.

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
(model number 90512 on the label on the back)

4.5v (3x AA rechargeable).

8 digits, red LED.

4-functions.

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

Made in U.S.A.
BOWMAR/ALI Inc.
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

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.

	Lecom 12

LECOM 12.

This hand-held calculator is missing its label on the back, and the IC inside has markings erased. Its Texas Instruments Klixon type II keyboard and the internal construction indicates that it is quite an early model (about 1973).

Does you know anything about the company Lecom and where it was made?
One suggestion is that Lecom stands for the London Electricity Company, can you confirm this?
If you have more information please get in touch.

Display is 6 digits, red LED, but can display 6 further less significant digits by pressing the arrow key.

6v (4 x AA replaceable batteries).

4-function, fixed decimal point switchable to give 0 or 2 decimal places.


		The 40-pin integrated circuit in this example has no markings, but someone with a similar calculator has it marked CT5002, by Cal-Tex. The circuit board also has 14 transistors (some by NS, date coded 7325? - ie. week 25 1973). Size 93x152x35mm / 3.75x6x1.5".

	Calculator Manufacturers


	GICO 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 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.*

Readers' Queries Below are some queries which have been received from readers of this site: Query 1

		Can you identify the calculator that this movie prop was made from ? John VanOlpen who is trying to find out says "It was a prop from a movie made in England in 1976, and according to the person who made the prop, they took the bottom part of a calculator, used it as a mold, and vacuum-formed these plastic boxes. The most distinctive features are the top and bottom edges which are angled, there are two grooves, and the rectangular detail on the top. Now its possible the rectangular detail was added when they vacuum formed the prop, but the grooves would have been part of the calculator along with the basic shape, flay sides, angled top and bottom. Its approximately 6 inches (15 cm) wide and about 8 inches (20 cm) long. Those measurements are approximate as they were measured from various photos, plus the thickness of the plastic used would add a bit to the overall dimensions. This is the bottom of the calculator supposedly. The grooves might have been for a power cord? The company that made the prop are in London, and it would have been made in 1976, so the calculator or adding machine they used would be from anytime prior to that era." The two grooves look highly unusual for a calculator and my have been cut into the casing before making the moulding. The rectangular detail at the top could be where there ia a socket to take an AC cord. If you can identify a calculator underside matching this description (with or without the two grooves) please get in touch with us and we will forward the information to John who will be highly delighted.

Query 2

Can you provide the model number of this Remington add-lister ? Any other details such as approximate year of manufacture would also be very interesting.

If you have information please get in touch with us.

Vintage Calculators