Manufacturer: A/S BRDR. CARLSEN
Model: D11
AKA: CONTEX D11
Year: 1971
Display: Monlithic Nixie-tube (8 digit)
Circuits: ELECTRONIC ARRAYS
(see further on this page)
Dimensions: 215x206x69 mm
Power type: 220V
Origin: Denmark
S/N: 024007509
Owner: DEVIDTS Serge
Info:  

Founded in 1925, REX ROTARY was originally a Danish company based in and around Copenhagen.
Their synergy with GESTETNER was that they too produced a dual cylinder stencil duplicator machines and
had by the mid 70's successfully diversified into electrostatic copiers and
more problematically into electro-mechanical calculators.
In 1974 GESTETNER purchased the complete REX ROTARY Company including the factories in Denmark and
the respected world-wide distribution which at least in part has been maintained up to the current day.
REX ROTARY UK is now part of the NRG Group Ltd, the UK subsidiary of GESTETNER Holdings plc, who
in turn are owned by RICOH Company of Japan.


Everything in and on these calculators is extremely well made,
even better than we use to see on HP-calculators,
they are certainly among the best finished calculators I've ever seen. 


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Display ^
There are three little indicators on the keyboard-front:
Minus-result, Overflow and 'shift-result possible'-indicator
Example of the latter:
99999999 [+] 6 gives 1 and a indicating arrow, with the [double arrow] key on the keyboard one can
switch between the two parts of the result (1 and 00000005)

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Internals ^

smd12429.jpg (39174 bytes)

Internals: Monolithic Nixie-tube ^

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Internals: Power-switch and one of the strange connectors ^

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Internals: chips: ^
IC's from ELECTRONIC ARRAYS, also one small T.I.-chip (7113)

1: 
2: 
3: 
4: 
5: 
6: 

  FDY: 150-5005
 FDY: 170-5017
 FDY: 180-5019
 FDY: 120-5013
 FDY: 110-5001
 FDY: 140-5004


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Examples and decimal-switch on bottom-side ^
There are two possible ways to adjust decimals:
One way is to push press the [..,..]-key on the keyboard and give in the number of decimals, then
pushing again (depress) the [..,..]-key. This setting of decimals is lost when turning off the machine.
Another way is via the switch on the bottom, this decimal-setting remains by switching off the calc.

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Label: support in Germany ^

Specific Instructions for the D11 ^
A (D11 / D31 / D51) instruction manual is can be found on the D51 model.



According this manual, there's another version of the D11 ^
with a flat keyboard design.