Type name / number: Astra 170 / 5 Bookkeeping machine
(very impressive out look and supposed functionality, but it is one of the simplest of the 170 series
Production / SN: 170/5 11539 (marked on one bottom bend). 332742 total production
Calculating principle: Rocking Segment technology
Calculating functions: "Five registers" in the following arrangement of "four counters":
  • three balance counters, with each one having "one register" These have add & subtract and positive- & real negative number, notation capabilities:
    • I & II located below the key board, at the left front
    • K located below the carriage at the rear of the machine.
      It is only accessible via the bridge programming, not via key's.
  • one counter with "two registers" with add and subtract capabilities
    (negative number results are presented in the nine complements notation):
    • III & IV located in the front, at the centre, below deck.
      IV is accessible by the key boards, via the III key's, when the
      switching function III -> IV on the program bridge is activated.

(to be continued)
Input accuracy 12 digits
Calculating accuracy: 12 digits
Machine description:

We're entering here the "Champions league" of mechanical calculators, the "Bookkeeping machines". They are used in offices for various administration tasks.

Introduction:
The Astra 170 class consists of a series of Bookkeeping machines, individual specified in terms of memory, registers and periphery. Special for all the 170 machines, with respect to the competition at those days, they are programmable. A bridge with cams/ ridges is used to store the program and thereby controls the sequence of calculations and printing.
The 170 series are one of the most complex mechanical calculators ever build and are successfully used in the accounting, administration, statistical and planing departments of many industries. They are exported in 101 countries. They have the possibility of inputting numbers and alphanumerical text, execute special functions (keywords), dates and calculate several numbers in parallel and printing those on a programmable / structural manner.
Some of this series booking machines have the possibility to communicate with peripheral units like a punch card readers, extra memory and multiplication units.
Robotron called the central rack of teeth bars, where those peripherals are connected to, the data bus of the machine. It is very smart to look at it in this way. The bars form a decimal- compared to the binary data bus, we see in nowadays computers!

The machine specification of this Astra 170/5 is, according manufacturer documentation, is as follows. The machine has:

  • No extra memory drum / carrousel
  • It has, an programming possibility. This is achieved by mount individual bridges on the carriage. These bridges have cams on it in a matrix lay out (x and y). The machine reads those rows of cams as function of the position of the carriage. On this way the calculation sequence is controlled by these cams. The carriage stops on certain positions, for instance to input a number, name etc. Constant numbers like fixe added tax value amount, can be stored in the registers.
    My machine has two bridges according the labels for: the salary and inventory administration.
    And according Robotron programming information check, fully correct / intact. It has one mysterious command, not documented for this machine
  • will be continued

More details to the machine series at the Robotron website
Designer: Mr. Hellfried Köhler
Production year: Between 1958-1959 Estimation based on:
- The machine were renamed from "Klasse 140" to "Klasse 170" in 1958.
- Astra was renamed to Ascota in 1959.
The last used date estimation is December 1973, the date printing head was still on that date. The day number is adjusted, I guess due to a to high number.

Production time window: 1955 and 1983. In the seventies the production was stopped, but restarted due to attractive Russian orders.

Is this one, one of the oldest available now??
When someone owns an Astra 170, with an smaller SN, please contact me for exchanging information!!
Case material: Bakelite
Weight: Kg
External links:

Robotron web site general

http://www.rechnerlexikon.de/artikel/Ascota_Klasse_170
Previous owner: Mr. P. Wallus, Düsseldorf, NRW, Germany
The machine was used by the Essers company in Düsseldorf (according labels on the bridge)
Cosmetic imperfections:
(I accuse no one)		 One corner of the bottom case is broken (not seldom with this Bakelite material). The paint is come off the case and bottom bucket. Front switch broken.
Date of receiving: 2012-11-07

Machine story:

Link to page 2

This text below is a growing document, an logging activities list, ranked on date.
This whole project is executed in close corporation with Rüdiger Kurth, Robotron webmaster and expert on the Ascota 170/xxx machines.

Transport and repair executed according the do's and don'ts of RK. I was rightly advised to put four wooden blocks below the four bearing surfaces, as a substitute for the frame where the machine is usually placed below the desks. The bottom box is not at that strong to carry the machine.

2012-11-12 First manual test
The electric motor uncoupled from the machine main axis (same as 110 and 314 machines). The motor still drives the carriage and front (ink ribbon + ?) mechanisms. The motor turned by hand on the rotor (no power of course!!) these mechanism seems to act normal. (not blocked). Manual (screw driver) try to turn the main axis back and forward is not possible. The machine seems to block on the 0 degrees marker.
First clean the machine "locally", to prevent dirty hands again (the electrical parts not removed. Removing the motor seems more complicated (than 110 and 314) due to the three driving wheels).

2012-11-13 Electrical components check
The mains switch, front site is broken, but one of the previous owner(s) have bypassed this double pole switch. So when the plug is connected to the mains, the machine is having power.
The box with the electrical components; RFI network and switch protected capacitor and resistors, is heated and the mains is switched off due to activation of safety leakage current switch. The classical problem of old capacitors. Have to investigate those.
Get a method from Rüdiger that it might be possible to regenerate those. I give it a try!
The speed regulator switch contacts are wear out heavily. (Status of protected capacitor ?) the contacts are not flat / horizontal but sloping.

remove key boards / broken piece
I was advised to remove the two key boards, the function- and alpha numerical one. My version of the 170 is slightly different from the ones who are at the Merseburg Museum, so the disassembly is, but the comparison of the pictures and the machine was bringing success. Many pictures taken for the ease of the assembly later on! To avoid bothering the general web visitor, I placed only those pictures on the web who are showing the new situation / free coming units. The two counters for instance, these are now seeing daylight.
The blocking of the central axis on the 0 decrease is not showing any cause here yet. Nearly all the cams are observable. By this careful examination of levers, who might effected, a steel piece was broken. It showed an fresh fraction. Not clear where it is from?? It felt down out the machine. Will be continued.

2012-11-22 main axis at 0 degrees, the catch and trap at the rest point
At the 0 degrees point, of the central axis, there are two catch and trap / catch holding  / pawl active. Namely one against the normal turns and one for the opposite direction. The last is above the normal clutch and the other somewhat hidden below. This gives the manual turning the feeling of a fixed blocking. Pushing the pawl above to the right, the opposite turning direction of the central axis came free. Until its 180 degrees point. The Printing bars came free. Holding those, against rapid movement to the rear of the machine.
The pawl below the zero degrees marker, the one for the normal direction of turning gives the axis free until it stops / hold at the 105 degrees point.
So the zero degrees catch and trap is a normal functional one, on the two directions of turning.
Slowly turning the main axis, in the forward direction,
  • I reached the 105 degrees point, no forward and turning back possibility.
  • It was hold there but not fixed, as it is at the 0 degrees point,
  • It had obviously difficulties to come over that 105 point.
  • the printing bars are out, but they not have not pushed them to the rear site of the machine yet (the actual printing).
  • A few times given it a somewhat more force and it went further at the 105 degrees point.
  • With an obviously noisy result and printing bar were launched from its hinged connection.
    Of course always on a moment that you do not expect it and forget to keep them within certain space the by hand. One spring is loose as well.
    (I will find out how to mount it again. Spring is more difficult I guess)

2012-11-23 reset counter 3/4 and prepare printing bars
After the launching the printer bars yesterday out of their hinge, I laid the machine on one side to made the surgical operation of repairing those bars more easily and mount the spring again. Having done that successfully, the examination of the counter below deck was a logical next thing to do. Don't know yet the complete working and control but here I saw a similar reset bar, as the two counter above deck have and the Astra / Ascota 110 and 314 machines have. Activate it due to a fixed strange position. This made the main axis free from holding at the 180 degrees position. Now I secured the printing bars by hand more consequently and turned the main axis the whole 360 degrees easily.
In the mean time I saw a marker beside de angular disk. This was the obvious point to indicate the actual angular position of the main axis. All above given values have been updated!!!

So bingo!
The to day conclusions !!

  • rest / end and start / stationary position of the main axis is at zero degrees (angular disk.)
  • holding at 105 degrees (resetting of counter 3/4 below deck is setting it free)
  • printing is at 150 degrees (all bars all at their maximum extension come out ?
  • What is actual machine cycle, which is executed here?
  • pin box mechanism of numerical key board is functioning.
  • ...

Continue at page 2
 
Summery / the short form "To Do " / "open issues" list, so far (not complete):
Description of activity / and comments to the work done Status Date
Motor leakage and capacitor investigation on rework or replace done 2012-11-28
Replace / rework speed regulator switch contacts?? done 2012-11-28
  Made the contact surfaces plan parallel done 2012-11-29
The reason for the blocking at 105 degrees. Is the counter 3/4 see further for the reason at the counter. (U form lever) done 2012-11-28
Tab test without and with motor and with and without carriage    
  Tab test with motor done 2012-11-29
  Tab test with motor and carriage done 2012-11-29
  Tab test with motor, carriage and bridge done 2012-11-29
     
Oiling here and there on machine and motor    
  Oiling the main axis, the counters and surrounding mechanisms done 2012-11-27
  Oiling the numerical pin box mechanism. It was blocked done 2012-11-30
  See the counter 3/4 mechanism if the are delayed due to old fat open  
Carriage "spring blade clutch" clean and readjust done 2012-12-01
Central axis "spring blade clutch" clean and readjust done 2012-12-01
  The reassembling of both clutches need an extra fasten lock nut tool. I have made that. And fasten the clutches.
 done 2012-12-04
What is reason for the need of resetting counter 3/4    
  Found that a U form lever should have a driving hinged point / disk was moving outside the U, in stead of being inside the U. Restore that in the right position, solves the blocking!!! done 2012-12-07
  The U lever; Check the consistency of the situation / will the hinged point stay within the U form lever??. Check if it is delayed by old fat?? done 2012-12-10
  Check the other counters on this issue. They are all right! done 2012-12-10
     
see where the metal piece is coming from open  
Clean the machine base frame bottom. (old oil and dirt) done 2012-12-10
Programming bridge How does it works.
 open  
  calculation sequences    
         
         
  print lay-out    
    see Functional test / tab lock simulation further on (partly solved) open  
         
         
         
     
     
     
Functional tests (continued with carriage and without bridge)    
  Standalone test of numerical key board / pin box check if the working is correct. done 2012-12-10
  Tab stop / tab lock simulation by wire, later by hammer. activate machine cycle is now possible.
done 2012-12-10
    printing bar execution only a few millimeters and no printing cycle. done 2012-12-10
    Why is a print not performed when no key is pressed, you might expect a print due to the leading zero mechanism. No function add or subtract is pushed??? open  
    When a number is entered, at the numerical key board, the printing bars are extend accordingly and a print is following. done 2012-12-10
    Red buttons register I and II add, subtract, subtotal and total seems to work properly doubts 2012-12-10
  The counting tests : add, subtract, sub total and total on Counters / registers I & II    
    Set the machine in the forward mode (very uncertain if the above test were done well. )
- removed the blue wire put the carriage on the machine ensure the forward mode (checklist)
Removed the pull wire (catch & trap at zero degrees) The buttons should do their work now
Performed the counting test manually of registers 1 & 2 by:
- entering numbers
- push red button Add subtract reg 1 or 2
- push gray buttons left and middle simultaneous (releases the catch and trap ... see next)
- turn the main axis manually
- look at the gear racks / registers / printing bars
Push the red buttons Sub total and Total (direct, no gray button is needed)
Negative numbers should print as real ones, fi -1 as 1 and sign and not in the nine complements notation 99998.
 done 2012-12-13
    Above counting test with motor on registers I & II
- connect the motor to the main axis. (Turn the blue metal catch ring on the angular plate)
- perform all the test as previous manual executed		 done 2012-12-14
  Either bridge programming or other counter tests ?    
       
       
       
  The counting tests : add, subtract, sub total and total on Counters / registers III & IV    
         
         
         
       
  The counting tests : add, subtract, sub total and total on Counters / registers V    
       
       
  Line feed and split roll    
    The line feed bar mounted on the way it should. Pull it to the front prior to the mounting of the carriage. The line feed rollers / levers takes control done 2012-12-15
    The paper roll is split table. Little cleaning on the pull out pawl and check the functions. done 2012-12-14
       
       
       
  Programming bridge How does it works. open  
    Prepare / build one bridge as test bridge with all the possible basic functions?    
    calculation sequences    
         
      open  
    print lay-out    
    see Functional test / tab lock simulation further on (partly solved)    
         
     
     
remount the two key boards    
functional test with the functional and alphanumerical key boards    
....    
clean the carriage front rusty parts    
     
repair the bottom case    
....    
     
     

 

 

 

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