One Hit Wonders




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	"One Hit Wonders"

This is a new article which was not originally in "The International Calculator Collector".

When the first hand-held calculators appeared in the early 1970s they were very expensive and many companies saw the opportunity of making a profit by manufacturing them. Some of these companies are familiar to us since they are still producing calculators today, having introduced dozens of models and sold millions of calculators over the years. Other companies manufactured a number of models but were hit by the plummeting price of calculators in the mid-1970s and departed the calculator business.

A third, and very interesting category, are those companies that saw the opportunity of hand-held calculators and manufactured just one or two models, but for one reason or other never produced any more. Often these "one hit wonders" were small companies and little or nothing is now known about them, but their calculators occasionally turn up. Many were American companies, but there must have been others elsewhere - Please get in touch if you have more information about the companies featured here or know of others that manufactured only one or two models.

Later, small companies bought calculators labeled for them from other manufacturers, usually in Asia, but these are not so interesting. Particularly in this category are the "Standard type 1" and the "Standard type 2" which are found with the names of many companies on them.

Below is a sample of these "One Hit Wonders":

Compumatic

Compumatic 8A

Display is 8 digits, red LED.

Power supply is 5x AA rechargeable batteries.

4-functions, using RPN (Reverse Polish Notation).
The key marked "CD & TG" is a dummy key and does not appear to have any function, but why is it marked so ?

The main integrated circuit is a National Semiconductor MM5725N, here date coded to the end of 1972.

Size 82 x 146 x 39 mm / 3.2" x 5.75" x 1.5".

c1972.

Made in U.S.A.
Compumatic
P.O. Box 3263, Huntsville, Alabama 35810.

Ramsgate

Ramsgate M-11

Display is 10 digits, red LED.

4-functions. Fixed decimal point, at 0, 2, or 4 places of decimals.

6v (4-AA batteries).

Integrated circuit is a Mostek MK5010P, here date coded late 1972.

76 x 147 x 31 mm. (3.0" x 5.75" x 1.25").

c1972.

Manufactured by Ramsgate Inc., Eveleth, Minnesota, U.S.A.

The Ramsgate M-11 is chunky and very solidly made.

The photograph above shows the battery holder of the M-11, which is one of most robustly made of any in a hand-held calculator and puts most others to shame.

The case has been opened to reveal the circuit board and the very unusual keyboard. The contacts are just bent strips of metal which are pressed by the keypads onto stud contacts set in the circuit board. This example is very prone to contact bounce causing multiple numbers to be displayed from one key press - this is probably made worse by tarnishing over the years.

Ian Jones International

Iain Jones International Addison Mini A

Display is 8 digits, red LED.

4-functions.

9v (PP3) rechargeable, see photograph of the rear, above.
Has a battery-level meter, just above the left end of the display.

Main integrated circuit is a General Instrument C550, here date coded early 1973.

80 x 149 x 28 mm (3.1" x 5.9" x 1.1").

c1973.

Designed and manufactured by Iain Jones International, Ltd, Atlanta, Georgia, U.S.A.

With the casing removed, showing the Texas Instruments "Klixon" keypad, and the circuit board with the gold coloured GI C550 integrated circuit, which was a very common calculator integrated circuit at this time.
To the right of the LED display is the battery-level meter.

JCE

JCE Mark II

Display is 8 digits, red LED.

Power supply is 5x AA batteries.

4 functions.

Main integrated circuit is Texas Instrument TMS0103, here date coded early 1973.

82 x 139 x 42 mm / 3.25" x 5.5" x 1.7".

John Colling Enterprises, Palo Alto, California, U.S.A.

Miracal

Display is 8 digits, red LED.

Power supply is 4x AA rechargeable batteries.

4 functions.

Main integrated circuit is CT5002, here date coded early 1973.

78 x 137 x 37 mm / 3.1" x 5.4" x 1.5".

P D Labs, 2120 Ronald St., Santa Clara, California, U.S.A.

Regan

Regan RA900P

Display is 8 digits, individual tubes.

Sealed power supply.

4 functions, memory.

94 x 143 x 46 mm / 3.7" x 5.6" x 1.8".

Regan Industries, Glendale, California, U.S.A.

RBM

RBM Scientific

Display is 8 digits, red LED.

Power supply is 6x rechargeable cells.

4 functions, %, square root, square, reciprocal.

77 x 142 x 31 mm / 3.0" x 5.6" x 1.2".

The main integrated circuit is a MOS MCS2523, here date coded late 1973.

RBM Corporation, Arlington, Texas, U.S.A.

This is quite a stylish calculator and comes in a presentation case so was probably expensive.

This calculator is similar to some models from Columbia Scientific, but the relationship between the companies is not known. If you have any information please get in touch.

Further "One Hit Wonder" companies, which manufactured just one or two models include: