Details:

The 16E is an exceptional machine advertised as semi-automatic.  Adverts state that it  contains semi automatic-multiplication and fully automated division.  However, multiplication is controlled manually and also division takes manual steps which other machines have automated.

Despite the limited automation this machine has a feature that isn’t often seen:  The Back Transfer can be applied to Register III (the result register), but also to Register II (the counter).  Thus it facilitates continued calculation after multiplication as well as after division.

Its external design is outstanding and awarded with an IFA design award.  
Not only the functionality is uncommon.  The internal design is a bit peculiar using three solenoids.  One is used to disable all key pushes while the calculator is operating.  A second solenoid takes care of digit entry making it feel like an electric typewriter.  A third one is used to activate the clearing of the three registers and to activate the back transfer.  Activation of the solenoids isn’t straightforward. It does take some circuitry to achieve a firm but short push of the solenoids.  If you want to know more about it, have a look at the diagrams in the assets corner of this website.

Usage:

Addition/subtraction/multiplication

As usual for this type of machine

Multiplication

Enter the 1st number.
Push the X+  button for repeated addition of the least significant digit of the 2nd number.

Shift Reg-I one position to the left and repeat the above step for the next significant digit in the 2nd number, etc.

Division          

Enter the dividend. Then move Reg-I all the way to the left using the fat arrow button. Push the ‘+’ key to enter the dividend in Reg-III.  Clear Reg-II.

Enter the divisor and again move Reg-I all the way to the left using the fat arrow button.

Start  the division by pushing the ‘:’ button.  It can be manually ended by pulling the ‘:’ button towards the operator.
The quotient appears in Reg-II,  the remainder is in Reg-III.

Note: after a division Reg-I does not return to its basic position.

Function of some keys, switches etc

• The black switch in the front of the machine is the On/Off switch.  When Off or when disconnected from mains all buttons are disabled.
• The arrow-down key above the register reset keys takes care of back transfer from Reg-III or Reg-II to Reg-I.
  Reg-I  must be manually brought in its desired position in advance.  The small arrows on Reg.I show the range of digits to be transferred. Note that it is possible to transfer the right part of Reg-I and left part of Reg-II with two zeros in between.
• The back of the machine contains a metal switch which when operated will force termination of a running division, e.g. after accidentally dividing by zero.
• In the bottom of the machine there is a switch which can lock Reg-I.   When the switch is set to the position indicated with a red dot,  it locks Reg-I.  Reg-I  must be set to the outer right beforehand.

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Serial number:

Built in:

Functions:

Rotation speed:

Market-introduction:

Production until:

Price:

1.6-0276.2v

Ca 1957 ?

Addition, Subtraction, Multiplication, Division

400 operations/min    (Set as low as possible to 300 operations/min)

1955

1959  (Büromaschinen Lexikon mentions it until 1961)

Approx. DM 1950,- in 1958;  DM 1680,-  in 1961 (from Büromaschinen Lexikon)