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Fialka machine

The Russian Fialka (which means "violet" in Russian) is a military encryption machine used during the Cold War. It was used to send classified information between Russia and various other countries, such as Poland, East Germany, and Czechoslovakia. 

Early versions of the Fialka were introduced as early as 1965, and it was used as late as the early 1990s. That is a tremendous run for a piece of encryption hardware! As these machines were removed from service, they were to be destroyed. I'm grateful that a few have escaped destruction and have found their way into museums and private collections. This machine is too remarkable to be forgotten.

Externally, the Fialka looks something like a large electric typewriter. It has a full keyboard with various letters and a space-bar. When it's on, the Fialka also sounds a bit like an IBM Selectric typewriter. But that's where the similarities end. There is no place to insert a piece of paper and no "Return" key or other formatting tools. Instead, it accepts 10mm or 17.5mm paper tape from an external spool on which it can print messages. It can even punch holes in the paper to represent the encoded message. An operator can then send this punched paper tape to the recipient, who can in turn feed the tape into another Fialka which will automatically read and decrypt the message very quickly.

The Fialka is similar in some ways to the German Enigma and the Swiss NEMA machine. These machines all operate with electromechanical rotors which move ("step") as the operator types the message to be encrypted or decrypted. The Enigma machine used either three or four rotors (based on the model), the NEMA used five rotors, and the Fialka used 10. But the Fialka has a number of other advantages over the these other machines besides having more rotors.

The Fialka also offers a paper-holder which can help operators who have to encrypt long or complex messages. In this picture, the holder is retracted and snapped to the top of the unit for shipment. It would appear that the creators felt that the cryptographic security of the Fialka was sufficient to allow for longer messages than were allowed on the Enigma.

This Fialka unit has support for both the Cyrillic alphabet as well as the Latin alphabet. It also has punctuation marks and numbers which is a major improvement over the Enigma and NEMA. If you look at the right side of the machine, you'll see a red and a blue button. The blue button starts the process of reading in punched paper tape, and the red button stops that process. Just below them on the front of the machine is the paper reading mechanism. A small snap at the top of that mechanism causes the cover to pop open, exposing the read head. An operator would insert the start of the encoded message, and close the cover. Assuming everything was set up correctly, the operator would only need to push the blue button, and the machine would read in the ciphertext, and character by character it would decrypt the message and print the cleartext on the internal printer.

The button protruding from the left-front of the device clears then character counter when pressed.

On the left-side of the unit is a slide-out drawer which houses a punch card reader. This card and card reader served the same purpose as the Enigma's Steckerbrett. The operator would place the daily key set up punch card into the reader, and the resulting effect is that certain keys would be swapped, increasing the cryptographic security of the message. The operator would only need to insert the card at the start of the work day. Compare that level of effort with the process of using patch panels on the Enigma's Steckerboard. In addition to being simpler to enable the day's setting, it's likely that mistakes in key setup would also be greatly reduced.


There are 10 rotors, labeled for the first 10 letters in the Russian alphabet (А Б В Г Д Е Ж З И К). Note that each rotor has black letters, which the exception of a single letter in red. 

That color coding system helps operators determine which rotor is where without having to take the rotors apart. This feature is important because it difficult to remove the rotors from the Fialka. To remove the rotors takes some practice, and patience. It takes two hands, one pressing the rotor cylinder down and the other releasing the two side levers.

It's interesting to note that the Fialka rotors step much more often than the Enigma rotors do. Even more interesting is the fact that a Fialka rotor will step in the opposite direction of its neighbors! These improvements make it much harder to break the Fialka cipher.

To further strengthen the cipher the designers introduced adjustable rotors in 1978 which could be modified in the field. For example, the core wiring mechanism for one rotor could be swapped with another.


The Fialka and power supply are quite heavy, together weighing over 50lbs (23kg). This is a very sturdy piece of equipment and must have been quite difficult to move around. I would imagine that it would be better suited for an office environment than field work. Other devices like the M-209 were designed with field-use in mind even under difficult conditions. The back of the cover has metal skids which become the bottom of the machine when the unit is held by the carrying strap.

The Enigma and NEMA both were used inside their carrying cases. An operator would unhook the front latch and open the cover, which was hinged on the back. Both of these other cases could be opened half-way, which made it easier to see the light-bulbs in the daylight. However, the cover to the Fialka comes off completely. Four snaps hold the cover in place for shipping, and when unhooked the cover comes off straight up.

Inside the cover, you'll find a number of important components:

  1. Gold-colored canister holding a spare set of rotors (see above)

  2. Chad collector box

  3. Paper tape spool

  4. Manual hand-crank

  5. Test reflectors

  6. Additional print heads

Some (perhaps all?) Fialka machines also shipped with a canvas pouch filled with a set of tools. These are extremely rare. Presumably most were destroyed.

Sample Encryption

The Fialka has several superior features to the Enigma. One of these features is that it sends its output to paper tape rather than simply lighting up light bulbs. That means a single operator can easily encrypt or decrypt a message simply by typing the clear-text or the cipher-text in front of him. 

Enigma was best used by two people: one who would press the keys, and the other who would write down the letters that lit up. Touch typing is not really possible on the Enigma because of the long distance each key must travel to complete the operation, and because it takes time to see which buld is illuminated in order to transcribe it. Touch typing is much more likely on the Fialka. Another improvement is that operators have the option of not only outputting printed characters, but they can also opt to have the output punched on the tape. This image shows an example of some text which hs been encrypted, with the output both printed and punched out. Note that the punched holes punch right through the paper tape, making it hard to read.

Not only can the Fialka punch holes, but it can read punched paper tape as well. Resetting the rotors to their original position, and running the tape through the tape reader will prints the original cleartext message. 

This is an amazing feature, and surely would have reduced the transmission error rate in addition to reducing the time to decrypt a message. However, for those cases where it was important to send the transmission over the air, or over wire, I wonder if there was a device which could read this punched paper tape and transmit something like Morse Code to a recipient.


Fialka Startup Checklist

These are the instructions I follow when I use the machine. But don't just rely on this checklist. Use your common sense, and if you are unsure of what to do, you should ask for help. In particular, always check to make sure that you have the power lines set up correctly. Since the Fialka has electrical parts, you can seriously damage the unit with the wrong voltage or polarity. If you have suggestions on how I can improve this list, please let me know.

Power Setup

  1. Make sure the main power button the on Fialka is off, which means set away from “BXЛ”.

  2. Push the “CTOП” (stop) button to make sure the tape reader is deactivated.

  3. Connect the the wall socket to the power converter: Plug the AC power cord into the top left socket of the power converter labeled “BXOД”, using the middle and right pins.

  4. Connect the power converter to the Fialka: Plug one end of the power cable into the upper-right socket labeled “MAШИNA”. Plug the other end into the Fialka with +24V going to the top pin. There should only be one way to plug the cable in if you have the right cable.

  5. Set the left-bottom dial to the center marker.

  6. Set the power source dial (labeled “НАПPЯЖЕНИЕ”) to “150”.

  7. Set the input source (labeled “CETБ ~”) to AC, which on the power converter.

Normal Setup (used for both encrypting and decrypting)

  1. The cipher-type setting can be set to encrypt letters and numbers (“30” setting), or only numbers (“10” setting). Set it to “30”

  2. The text-mode can be set to letters-only (Б), numbers-only (Ц), or mixed (C).

To Encrypt

  1. The cipher-mode setting can be set to plain-text (O), encoding (З), or decoding (P). Set it to “З”.

  2. The printer can be set to “print and punch” (ПФ), or “print only” (ПЧ). Set it to “ПФ”.

  3. The Send/receive lever should be set to the left.

  4. Push the the 5-letter spacing lever back towards the round button. This will make sure the output is spaced in groups of 5, which will make it easier to transmit.

  5. Set the rotors to the chosen key.

  6. Push the character counter reset button to set the counter to 0.

  7. If you have a key setup card, you can replace the metal triangle with the paper key card.

  8. Type the message to be encrypted. It will appear on the paper tape.

To Decrypt

  1. The cipher-mode setting can be set to plain-text (O), encoding (З), or decoding (P). Set it to “P”.

  2. The printer can be set to “print and punch” (ПФ), or “print only” (ПЧ). Set it to “ПЧ”.

  3. The Send/receive lever should be set to the left.

  4. Push the the 5-letter spacing reset button.

  5. Set the rotors to the chosen key.

  6. Push the character counter reset button to set the counter to 0.

  7. If you have a key setup card, you can replace the metal triangle with the paper key card.

  8. If you are typing the message, you may do so now. If you are reading it in from the paper tape, insert the paper tape and press the “ПYCK” button. The Fialka will read the tape in, and decrypt quite quickly.

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