Three Navigation Calculators
By the mid-1970s the standard electronics for calculators was well developed and companies turned to producing calculators for more specialised calculations. One of the areas that was suitable for specialised calculators was navigation, by sea or air, and several models were soon on sale, including thos hown here.
Specialized Electronics Corporation Navtronic 16
Specialized Electronics Corporation (SEC) Navtronic 16.
Display is 8 digits, red LED.
4-function.
Main integrated circuits - National Semiconductor NS MM5728N and MM57129NBL/N, here date coded mid 1976.
6v (4 x AA batteries) .
81 x 151 x 38 mm (3.2" x 5.9" x 1.5").
Specialized Electronics Corporation, 4428 North Elston Ave., Chicago, Illinois 60630.
This is a very specialised calculator and had integrated circuits dedicated to navigating in aircraft.
Tamaya NC-77
Tamaya NC-77 Digital Navigation Computer.
Display is 10 digits, green fluorescent.
Scientific and navigation functions.
Integrated circuits - Surface mounted, types SC38664 and SC38665 date coded early 1978.
6v (4 x AA batteries) .
82 x 150 x 27 mm (3.25" x 5.9" x 1.1").
Produced from 1978 to 1991.
Tamaya & Company Limited,
Tokyo, Japan
Made in Japan.
Tamaya is a well known manufacturer of navigation instruments. It has a website which gives the above production dates.
The website also gives details of how to use the calculator into the year 2000 and beyond. By entering
the date as the 99th day of the 99th month of 1999 !!! it is possible to use it up to June 23 2007. A table to print out gives all the necessary conversions.
If this is too troublesome you can buy the latest model the NC-2000.
This is also a very specialised calculator using dedicated integrated circuits. The fitted wooden case is evidence of the respect which Tamaya had of its intruments.
Production over the the 14 years of 1978 to 1991 is probably a record length of time for any electronic calculator of the 1970s. It is beaten by the Hewlett Packard 12C financial calculator which was introduced in 1981 and is still in production.
The Tamaya NC-77 appears to have been manufactured by Sharp - the casing closely resembles that of the Sharp EL-8018.
