Have a Look at the "Manual Precursor", the FACIT-T (= Advertisement )
  Have a look at the HOME-MADE  A N G L E  POWER PLUG for 220 VAC ...

   The broken black ZERO-Key got a RED RING for stability with purpose:
      Because out of sequence, this RED enhances its special position

TECHNICAL DATA       of the Electro-Mechanical Calculator         FACIT EK
**************************************************************************
                                                          (Plate missing!)
Serial Number:       8782   (= Engraving on bottom)

Dimensions:   (ca.)  Width   =  11    " /  28 cm
                     Depth   =   9_1/2" /  24 cm
                     Height  =   6_1/4" /  16 cm

Weight:       (ca.)  22 lbs  /  10 kg

Power Supply:        115 V / 20 W  ( AC / DC )

Mechanics:           10-Keyboard (DALTON type)
                     Serial-to-parallel conversion with
         Principle:  Pin-Wheel / Sprossenrad
           Special:  FACIT's Solution

Functions:           Add, Subtract, Multiply, Divide

Registers:             I  Input       =   9 Decimals
                      II  Counter     =   8 Decimals
                     III  Arithmetic  =  13 Decimals
Manufacturer:
                     FACIT
                     Atvidaberg
                     Sweden
                     1940

BASICS  &  HOW TO USE  the FACIT EK
***********************************

(A) Clearing Registers:
-----------------------
The LEVER-PAIR on the left side is for clearing registers (III)&(II) per
hand. The input unit (I) will be RESET & CLEARED by MOTOR POWER in
pushing the right RED [0] BUTTON. After this clearing cycle the input
keys [0], [1], ... [9] are enabled.

(B) Shifting the Input Unit with the Entered Number:
----------------------------------------------------
Left of the number keys, the RED KEY-PAIR let the input unit STEP left
[<-] or right [->]. The actual position is marked with a red arrow-pair
ref. to reg. (III) & (II). Right of the number keys, the RED [DIV] KEY let
the input unit JUMP to the most left position - but the arrow-pair stops
at pos. 8 of the counter - and the input will be filled up with zeros.

(C) Counting Direction:
-----------------------
After clearing the counter unit (II), it depends of the first ADD/SUB
operation, that the counter will go either (+) or (-). In case of (+) the
counter & arithmetic unit are working in the same; in case of (-) both
are working in opposite direction. This is shown with a RED INDICATOR at
the right of the counter unit.

(D) The Toggle Lever on top has 2 Positions:
--------------------------------------------
     up  =  Input register is NOT CLEARED after each DIV/MULT cycle.
   down  =  Input register is CLEARED after each SUB/ADD cycle.

(E) Functions:
--------------
The MINUS [-] & PLUS [+] keys are MOTOR POWERED.

      +  =  Add              Addend + Addend = Sum
      -  =  Subtract         Minuend - Subtrahend = Difference
      x  =  Multiply         Multiplicand x Multiplicator = Product
      :  =  Divide           Dividend : Divisor = Quotient

Prior to each task the 3 REGISTERS (I), (II), (III) have to be CLEARED.

ADDITION & SUBTRACTION:
=======================
Example:    123 + 45 - 6  =  162

Set the toggle lever to SUB/ADD.

ADD: Enter the first number (123) into input register (I). Press the
PLUS [+] key to transfer the input (I) into arithmetic unit (III). The
counting unit (II) displays the figure 1. Enter the second number (45).
Press the PLUS [+] key to add the number. The arithmetic unit (III)
displays the intermediate sum (168) and the counting unit (II) displays
the figure 2.

SUBTRACT: Enter the third number (6) into input unit (I) and press the
MINUS [-] key. The arithmetic unit (III) displays the result (162) and
the counting unit (II) is decreased by 1.

REMARK:     NEGATIVE RESULTS are displayed in the arithmetic unit (III)
            as the COMPLEMENT of the next higher 10, 100, 1000, ...

            Example:   -12  =  99...9988

MULTIPLICATION:
===============
Example:    123 x 45  =  5535

Set the toggle lever to DIV/MULT.

Enter the multiplicand (123) into input unit. Press the PLUS [+] key,
until the second figure of multiplicator (5) will appear in the 1st
position of counter unit. Move the input unit with the STEP [<-] key to
position 2. Repeat pressing the PLUS [+] key until the first figure of
the  multiplicator (4) appears in the 2nd position of the counter unit.
The multiplication is done: The multiplicand (123) stays in the input
unit, the multiplicator (45) is in the counter and the result (5535) is
in the arithmetic unit.

DIVISION:
=========
Example:    22 : 7  =  3.1428571  Remainder 3

Set the toggle lever to DIV/MULT.
Division requires 3 steps:

(A) To Set the Dividend into Arithmetic Unit:
    -----------------------------------------
    Enter the dividend (22) into input unit. Press the JUMP [DIV] key.
    Press the PLUS [+] key to transfer the input into arithmetic unit.

(B) To Set the Divisor into Input Unit:
    -----------------------------------
    Clear the counter unit. Clear & reset input unit with the red (0)
    button. Enter the divisor (07) into input. Press the JUMP [DIV]) key.

(C) To Divide:
    ----------
    Press the MINUS [-] key (now the red indicator is on) until the
    machine stops because "underflow". Make one PLUS cycle. Move the
    input unit with the STEP [->] key one position to the right.

    Press the MINUS [-] key again ... and repeat this procedure until the
    required number of decimals are calculated...

    The result (3.1428571) is in the counter unit, and the remainder (3)
    is in the arithmetic unit. The divisor (7) stays in the input unit,
    therefore an additional decimal can be estimated...
    ( 4, cause 4 x 7 = 28).

                     Have a look at "Calculating Trickies" ...
impressum:
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© C.HAMANN           http://public.BHT-Berlin.de/hamann           08/27/07