| Type number / name: |
Astra 150 Bookkeeping machine (Astra 150 Buchungsmaschine (DL)) Astra later renamed to Ascota.
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| Production / SN: |
150 - 7542 (marked on one bottom bend). as well as : 37 / 1431 / 1001 |
| Calculating principle: |
Rocking Segment technology |
| Machine description: |
This very impressive machine has a more than average mechanical calculator functionality, it is one of the early versions of the 170 series.
We're entering here the "Champions league" of mechanical calculators, the "bookkeeping machines". These machines are used in offices for various administration tasks.
Now, in the computer time, we would call it simple spread sheet of application.
Introduction:
The Astra 150 is a precursor of the 170 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 the calculator units and the 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 instead of a binary data bus, we see in nowadays computers!
The Astra 150 specification:
- Five extra memory registers in a drum / carrousel configuration
- 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.
- will be continued
More details to the machine series at the Robotron website |
| Calculating functions: |
"10 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.
- five in a drum / carousel type of arrangement
(to be continued) |
| Input accuracy |
12 digits |
| Calculating accuracy: |
12 digits |
| |
|
| Designer: |
Mr. Hellfried Köhler |
| Production year: |
|
| Case material: |
Bakelite |
| Weight: |
Kg |
| External links: |
Robotron web site general
|
| Previous owner: |
Mr. Pries, Stapelfeld near Hamburg, Germany
The machine was used by the company "Pries Kunststofftechnik", established by his father. . |
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: |
2013-10-21 Ebay buy, Picked him up in Hamburg, after a getting the availability tip of Ruediger Kurth |
Machine story:
|
2014-02-22 / 2014-02-27
The machine some what cleaned on the outside. It is remarkable good kept. No blocking is seen yet.
Made pictures of the outside and internal configuration.
First examination shows a lot of common mechanics compared to the 170/5.
As extra functionality to is the register drum. The drum is stacked with 5 registers clearly seen with the control mechanics. The drum have probably not been used. The vet is in one row still, like the first usage.
The "decimal data bus" is divided in parts. The rack is having tooth on one position to hook an extra peripheral.
2014-0217- 2014-03-03
Performed some initial test first according the same procedure as the 170, removed programmable bridge and the huge carriage. But now I left the alpha keyboard and bookkeeping functions keyboard in place for these first tests.
- Sprayed the machine internally with W40.
- See if the pin box is entering the numerical numbers. Yes it does.
- Uncoupled the electrical motor and see if the calculator functions are free. Here I discovered a different configuration. The scale with the zero marking is not there and the pawls configuration is different. But making it free from turning by hand the main axis was free to turn. Forgot to hold the print bars (like I forgot on the 170) so a few bare came loose. Not bothering that now.
- the print bare were hold at the maximum out position. Like the first tests of the 170. Turning the motor by hand and put the coupling in function again, the situation was set back to the rest position again.
- putting the electricity on and repair the electrical switch. The temperature of the capacitor block stays normal. No heating.
- Checked the clutches on the main axis by hand. it is still working.
- Put all the switches on the keyboard in the upper position. And the one near the numerical function keys to the right.
- Put the carriage on the machine again. Made the decision to check the electrical motor. It was turning. Put the clutch in function and started with a tab function those all worked well!!!!
- I tried to performed a calculation on registers 1 and 2. They seems to work, (but due to the missing print bar on the lower digit not fully clear.)
- Put the switch alpha keyboard on and the characters are printed. Some are banded a little and the spring was not bringing the up again. Have to repair those. And the character block pushing to the numerical printing bare two of them became loose. A pity but although it is very difficult to put the on place again, it is repairable. The coarse is the not fully restoring of the bars in the rest position. (dry out hinge??)
- The date, 29 IV 73, which was probably the last usage date, was printed with some red functional key's to the right, when the switch near the numerical function keys, was set to the left.
- The drum position is selected by the 5 key's. The zero is not possible to operate yet. The way a register is selected was surprising me. It is conducted by the motor a the drum axis seem to turn fast until the selected register is in position to set it on the data bus.
Storing a number is I belief only possible by the program bridge.
- Printing is working even the ribbon is not dried out!!.
- After a view test in the forward mode and the hammer pushing against the mechanical switch on the carriage, I tried to see what the effect was of the mounted bridge.
- I tried it by mount the program bridge , not knowing what the functions on the given bridge are, it was nice to see that in certain carriage positions, a tab push had the effect of a carriage return and line feed, print a few numbers (3) and stopped. This was also executed when the red buttons are pushed, in nearly end locations of the carriage.
This I have not analyzed exactly, but for now I am pleased, knowing that a certain function is executed by control of something else than the keyboard.
- A keyboard switch for register K can be set, but I do not know how it is controlling?
- will be continued
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