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Fialka key card
30 x 30 matrix punched card

To enhance the cryptographic strength of the machine, the M-125 Fialka has a card reader at the left bottom. Each day, a fresh small piece of paper with a series of punched holes was entered in the drawer of the card reader. The functionality of the card reader is similar to the plug board (German: Steckerbrett) of the Enigma, but is easier to use and is cryptographically stronger.
Not many original Fialka punched key cards have survived because - as per protocol - they were all destroyed immediately after use. So far, we've only seen one original card, which is shown in the image on the right. Many thanks to Tom Perera (US) [2] for donating this card to us.

In the image on the right it is clearly visible that the card was torn from a stack, as the top part is missing. The number 23 in the top left corner refers to the day of the year. The key cards were changed daily and they were created by the Russians for all countries of the Warsaw Pact.
An original Fialka key card in the card reader

Each country had its own unique stacks of cards, each valid for one month. The stacks were created by the Russians, for one year in advance and were supplied in a seal bag. The cards were perforated at the upper and lower edges. When taking a card from the seal bag, it was ripped off at the lower edge, whilst the upper edge was used to align the card with the two index pins in the reader. The number of the card (i.e. day of the year) was printed along the upper edge of the card and was visible through a cut-out in the seal bag. Each day, the Fialka operator took a card (with the number corresponding to the day) from the seal bag (see below) and placed it in the reader.

The cards were so thin that they could only be used once. Opening the drawer of the card reader a second or third time, was likely to damage the card. This was deliberately done to ensure that a card would not be used again. In situations where no key card was needed, a metal triangle was used instead. It forces the identity matrix to be used and is similar to an Enigma plug board with no cables. Reproduction key cards are available from two sources, both of which are listed below.
Original Fialka key card Original Fialka key card Original Fialka key card, (day) number detail Placing an original Fialka key card in the machine An original Fialka key card in the card reader Closing the card reader The day number visible to a small window Closing the drawer and raising the bar

Seal bag containing the key cards and the wheels settings for one month [3]

Metal triangle
Most Fialka machines found on the surplus market, are supplied with a metal triangle in the card reader. basically, the triangle iliminates the card reader by forcing the identity matrix, or diagonal, to be used. This means that A is translated to A, B becomes B, C becomes C, etc. Using the test triangle is comparable to removing all patch cables from the Enigma's Steckerbrett.
As per protocol, the key card was removed at the end of the day (or session) and replaced by the metal triangle. The original key card was then destroyed. This way, no useful information was left behind in the machine. The metal triangle was also used for excluding the card reader from the equation when testing the machine.

Theoretically, it is also possible that the triangle was used when a less secure key was needed, for example when exchanging messages with other Warsaw Pact countries, but no evidence to support this claim has been found to date.
The metal test triangle in place

The Russian text ВЕРХ, engraved at the upper edge of the triangle, means 'TOP' (this side up). If there is is no card and no metal triangle, the machine can not be used, so you may want to create a reproduction of it. An accurate drawing with the precise dimensions is available for download below. Alternatively, a key card with a diagonal row of holes could be used as an equivalent.
The metal test triangle for the Fialka card reader Holding the metal test triangle Holding the metal test triangle Close-up of the upper edge of the test triangle The text BEPX (this side up) at the upper edge of the triangle Placing the metal test triangle in the card reader The metal test triangle in place

Reproduction key cards
Although it is perfectly possible to operate the Fialka with the metal triangle placed in the card reader (see above), it is best demonstrated with suitable key cards in the drawer. As nearly all original key cards have been destroyed, you might want to get a pair of matching reproductions.
Günter Hütter
In 2007 Günter Hütter in Austria created a series of replica key cards that can be ordered directly from him. The cards are punched with a purpose-built puncher and are sold in sets of two. They work perfectly well with every Fialka we have tried.

We should like to thank Günter for sharing the results of his experiments and for confirming that the dimensions given below are correct.
Two identical reproduction cards with serial number 154 (Günter Hütter)

Mark Sims
Another successful attempt to create high quality reproduction key cards was mounted by Mark Sims in 2014. His key cards are fully laser-cut and contain every detail that can observed on the original.

These cards can be ordered directly from Mark Sims, who can be contacted at his e-mail address holrum@hotmail.com [4].
Two of Marc Sims' Fialka key cards (reproduction)

M-125 Fialka with open card reader Two identical reproduction cards with serial number 154 (Günter Hütter) A collection of Fialka reproduction key cards Reproduction key card (Günter Hütter) in an M-125 Fialka key card by Mark Sims (reproduction) Two of Marc Sims' Fialka key cards (reproduction) Fialka reproduction card placed in the card reader Close-up of a reproduction Fialka key card with S/N 132


Below is a drawing of a key card with all holes punched. In case you want to create your own key cards, you may want to use this drawing as a mask and punch out the required holes: one for each row/column combination. Click the image to open it as a 1:1 PDF file, or download it below.

Key card mask. Click to download.

Test triangle
Below are the dimensions of the metal test triangle that is normally present in the card reader of a Fialka, when the machine is unused. If this triangle is missing from your machine, you may be able use these dimensions to create a reproduction. Click the image to download it as a 1:1 PDF. The Russian word ВЕРХ, engraved along the upper edge, means TOP (this side up).

Metal test triangle. Click to download.

Example Key Card #14
Below is a drawing of a key card with serial number 14, just as an example. As you can see, there is precisely one hole for each row/column combination. If you want to create your own Fialka key cards, you may want to download and print this one. Click the image to download it as a 1:1 PDF.

Key card #14. Click to download.

Identity matrix
In case the metal test triangle is missing from your Fialka machine, and you are not able to make a proper reproduction of it, you may want to use the identity matrix key card shown below. It contains a diagonal of holes and is the equivalent of the metal triangle (A→A, B→B, C→C, etc.).

Identity matrix key card. Click to download.


    Universal key cards. (836KB PDF file)
    This is a single page that contains four blank universal key cards. Print this page at actual size (100%) and cut the four cards apart. Next create the alignment holes and the actual key holes.
    Sample key card # 014. (65KB PDF file)
    This file is similar to the one above, but rather that showing all possible hole locations, it prints the holes for the sample key card number 014 as printed in the German Fialka Manual.
    Metal test triangle. (12KB PDF file)
    The metal test triangle should be present with your Fialka. It should be used when no key card is present in the card reader. If the key card is missing, you might want to download this file and print it on sturdy paper (e.g. 150 or 200 grams).
    Identity matrix key card (13KB PDF file)
    Use this card as an alternative to the metal test triangle in case the latter is missing. This card is the functional equivalent of the metal test triangle.
  1. Paul Reuvers and Marc Simons, The Fialka M-125 Reference Manual
    Copyright 2005-2009. Version 2.0, June 2009. ISBN 978-90-79991-01-3.

  2. Tom Perera, General Introduction to M-125 Fialka
    Retrieved July 2008.

  3. Jörg Drobick, Nutzung der Fialka M0125
    Website: Der SAS- und Chiffrierdienst (SCD). Retrieved May 2014.

  4. Marc Sims, Reproduction Fialka key cards
    Copyright 2014. Card can be ordered by following the link above.

Further information

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© Crypto Museum. Created: Saturday 31 May 2014. Last changed: Monday, 12 October 2015 - 14:39 CET.
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