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Last Update: Oct 05, 2011 -- THE CURTA REFERENCE Curta I --->


NEW!     FACTORY PRODUCTION LISTS RELEASED!     (Oct 03, 2011)

These lists were produced by a former Curta Factory worker. Thanks to Hans for providing them.

CURTA I
Year      Serial number         pieces produced
1947 901 - 3,0002,100
1948 3,001 - 6,000 3,000
1949 6,001 - 9,200 3,200
1950 9,201 - 12,6003,400
195112,601 - 16,6004,000
195216,601 - 20,6004,000 CURTA II
195320,601 - 24,4003,800 YearSerial number              pieces produced
195424,401 - 28,2003,800 1953/54500,001 - 505,1205,120
195528,201 - 32,0003,800 1955505,121 - 507,1202,000
195632,001 - 35,8003,800 1956507,121 - 510,0202,900
195735,801 - 38,8603,060 1957510,021 - 510,520500
195838,861 - 40,7701,910 1958510,521 - 511,5201,000
195940,771 - 41,7701,000 1959511,521 - 513,5202,000
196041,771 - 45,0103,240 1960513,521 - 516,5203,000
196145,011 - 49,1704,160 1961516,521 - 519,0202,500
196249,171 - 52,8803,710 1962519,021 - 522,5203,500
196352,881 - 56,1303,250 1963522,521 - 526,1203,600
196456,131 - 58,5802,450 1964526,121 - 530,3204,200
196558,581 - 62,1803,600 1965530,321 - 533,9203,600
196662,181 - 65,7803,600 1966533,921 - 539,3205,400
196765,781 - 68,7803,000 1967539,320 - 544,7205,400
196868,781 - 73,5804,800 1968544,721 - 549,5204,800
196972,581 - 77,7804,200 1969549,521 - 554,9205,400
197077,781 - 80,4272,647 1970554,921 - 560,9206,000
1971560,921 - 561,660740
total production: 79,527 total production:61,660


Month Key
0- Jan -1- Feb -2- Mar -3- Apr -4- May -5- Jun -6- Jul -7- Aug -8- Sep -9- Oct -10- Nov -11- Dec -12

CURTA I DATE CALCULATION FORMULA

CURTA I : YEAR = 1947 + ( SERIALNR / 80,000 ) x 24

Example: Serial Number = 15045

1947 + (15,045/80,000) x 24
1947 + .18806 x 24
1947 + 4.5135
1951.5135
12 x .5135 (now take the fractional part and convert to months)
6.1620 = early July
~ July 1951

Example: Serial Number = 58562

1947 + (59,862/80,000) x 24
1947 + .74828 x 24
1947 + 17.9586
1964.9586
12 x .9586 (now take the fractional part and convert to months)
11.5032 = Mid December
~ December 1964

CURTA II DATE CALCULATION FORMULA

CURTA II: YEAR = 1954 + ( (SERIALNR - 500,000) / 70,000 ) x 17

Example: Serial Number = 526699

1954 + ((526,699-500,000) / 70,000) x 17
1954 + (26,699 / 70,000) x 17
1954 + .3814 x 17
1954 + 6.4840
1960.4840
12 x .4840 (now take the fractional part and convert to months)
5.81 = late June
~ June 1960

Facts from Rick:


Notes and Original Formula From Erik van Dam:

I found somewhere that there are +/- 80000 Curta I and 60000 Curta II machines.

They were made from 1948 until +/- 1972 so if they have made the same number of machines every year, and I am sure they did not, you could use the next formulas to calculate the estimated year of production:

Curta I : YEAR = 1948 + ( SERIALNR / 80,000 ) * 24
Curta II: YEAR = 1948 + ( SERIALNR / 60,000 ) * 24

If the production numbers are correct you should be at least somewere in the right direction.

It is possible that there is a offset that has to substracted from the serial number first. So if anyone can tell the lowest and highest serial number for the Curta's I and II then I can perfect the formula!

Erik van Dam
0vdam03@flnet.nl


From Reinmar Wochinz:

The production of the Curta I started with #1, the Curta II started with #500.000. The number of Curtas produced is approximately what Erik van Dam stated.

I myself have three Curtas at the moment:
#32.133 Curta I (open demonstration model)
#55.176 Curta I
#512.754 Curta II

Curtas I had in the last few years were
Curta I: #38.100, #54.788
Curta II: #515.417, #531.566

Reinmar Wochinz
Vienna - Austria
rwochinz@pop.tuwien.ac.at


Notes from Rutger Verbeek:

I have a very late (unused) Curta II, serial number 560608. I think that the last 5 digit are the production number.

Rutger Verbeek
Rutger.Verbeek@FernUni-Hagen.de


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