History of the Hagelin Cipher Machines
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This is the story of Boris Hagelin, a brilliant engineer, and his famous cipher machines. He is the only inventor and developer of crypto machines in history to have made a fortune in that market. Hagelin and Crypto AG are still most respected names in the world of crypto machines and have dominated the commercial market of cryptology for many decades.

The Man and the Firm

Boris Hagelin

Boris Hagelin was born on July 2nd, 1892 in Adschikent, Russia. His Swedish father sent him to Sweden, where he graduated in 1914 as mechanical engineer. His future was already planned in the Nobel company's Oilfields, where his father was the manager. Initially, he specialized in electrical engineering in order to become supervisor of the construction of an electric power plant for the Nobel Company in Baku. After the revolution in 1920 the Nobel family entered into a partnership with the Standard Oil Company in the US, and Boris moved to the US to work in their General engineering Department. After one year he returned to Sweden.

Emanuel Nobel asked Boris Hagelin to supervise a small Swedish company, A.B. Cryptograph, which manufactured ciphermachines, invented by the Swedish engineer Arvid Damm. In 1925 he took over management and started developing new machines. In 1932 A.B Cryptoteknik replaced the liquidated A.B. Cryptograph. After the Second World War Hagelin moved to Zug, in neutral Switzerland and established Crypto AG. This relocation was required since Sweden considered Cryptographic equipment as weapons, and thus prohibited their export. The pre-war reputation of mechanical "Hagelin Cryptos" devices and the need for enciphered telegraph equipment helped the firm to grow and laid the foundation for a new generation of electronic cipher equipment. Boris Hagelin died in 1983 at the age of 91.

Hagelin B-21 and the First Success

In 1925 the Swedish General Staff contacted A.B. Cryptograph to design a machine that would be superior to the German Enigma. Hagelin developed a prototype for evaluation called B-21. The B-21 was approved for the Swedish General Staff and Hagelin also sold the machine to several other countries. Its principle was based on Arvid Damm's simplified rotors, a 5 x 5 grid design. The machine had a keyboard, 2 rotors of which the stepping was controlled by two pairs of pin-wheels and a display with 25 lamps that presented the output of the en/de-cipherment. The machine was operated on 110 or 220 volt and the lamp panel was powered by a battery. Depressing a key would close two contacts, each contact in one of two groups of five contacts. The signal then passed through two rotors to the 25 lamps. Interchangeable leads, in series with the rotors, could be connected as desired.

This machine was the first to apply pin-wheels, a feature that was used in many of its successors. A pin-wheel is a disk with a number of axial holes in which pins are located. These pins can be moved either to the left or to the right side of the disk. On one side, these pins are inactive, on the other side active. With each step, the pin-wheel moves one pin position. Several different pin-wheels with different numbers of pins without a common factor are used to obtain a very long key period.

In 1932 the French Army was interested in the B-21 but asked for two important modifications. The machine had to be portable and should be able to print the text. Hagelin developed the B-211 which could be operated either with electric power or by hand with a crank. He replaced the lamp panel with a type-wheel printing mechanism and the ciphering circuits were powered by a battery. About 500 B-211 machines were built. In 1940 Hagelin installed a workshop in Sweden with the profits of the successful B-211 and A.B. Cryptograph was renamed in A.B. Ingenieursfirman Cryptoteknik.

More about the B-21 on this page.

Image  John Alexander

Hagelin B-21

The C Type Machines

Already in 1934 the French Cipher Bureau asked Hagelin to develop a compact cipher machine that could also print. Hagelin got the idea to adapt a calculating mechanism from a money changer into a small crypto device. The infamous pin-and-lug machines were born.

The first machine, the C-35, consisted of a drum with 25 bars, five pin-wheels (identical to the ones used in the B-21) and an alphabet-knob/type-wheel with reciprocal alphabet (type-wheel alphabet reversed to knob alphabet). By using a reciprocal encryption it was very easy to switch between enciphering and deciphering. The text was printed on a small paper ribbon. The compact device had the size of a small lunch box. Military personnel could put it in a side pocket of the uniform.

To encipher a letter the operator turned the alphabet knob to the desired letter and turned the handle at the right side of the machine. The type-wheel, fixed to the alphabet knob, then turned a number of steps, depending on the settings of the machine. The enciphered letter was printed on the paper ribbon or the operator could read off the reciprocal alphabet on the knob. The wheel-pins were set each day according to a key sheet. Before each enciphering of a new message, the operator would set a new start position of the 5 pin-wheels on the exterior.

US M-209

The movable slide-bars on the drum contain fixed lugs. When the drum is revolved with the handle outside the machine, the different lugs pass 5 cams that are under control of the pins on the five pin-wheels. If a pin is active, the cam of that wheel will push a passing lug to the left. The slide-bar on which that lug is fixed will also move to the left and comes out of the drum as a small teeth. The left side of the drum will therefore act as a gear wheel with a variable number of teeth, engaging the type wheel. The number of tooth, and thus the displacement of the type wheel, depends on the settings of the lugs and pins.

The 5 wheels had 17, 19, 21, 23 and 25 pins. Since these numbers have no common factor the same wheel setting would only occur once every 3,900,225 steps. On top of this, there were theoretically 10E29 different possibilities to set the many pins on the wheels.

An improved version with protective casing and another lug arrangement, and later on with movable lugs on the drum, was designated C-36 and. Its successor, the C-38, had six pinwheels. The lugs on this machine could slide on the drum bars in one of 5 active or an inactive position. This improvement, together with the larger wheel period, provided a very large key space. Another version, designated BC-543, was fitted with a keyboard.

In 1940 Hagelin went to the USA to promote his C Type machines which resulted in the largest sale ever of crypto machines. The US military selected his C-38 as tactical ciphering device and designated it as M-209. By the end of the Second World War over 140,000 of these small M-209 machines were produced in the US. A simulator of the M-209 can be downloaded on this page.

The C-52 and CX-52

Although the C-36 and C-38 were ideal for tactical purposes they were insufficient for the enciphering of high level message traffic that could resist extensive cryptanalysis. An improved version would open the door to the market of high level military and diplomatic encryption. Hagelin went back to the drawing table to improve his C Machines.

Several improvements were introduced in the C-52 model. The rotation of the pin-wheels became irregular. Whether a wheel moved or not on a given cycle depended on the pin positions of the previous wheels. For the 6 wheel model there was now the choice between 12 pin-wheels, with 25, 26, 29, 31, 34, 37, 38, 41, 42, 43, 46 and 47 pins. The number of slide-bars was increased to 32. A second type wheel was added to print both plain and ciphered text at the same time on a split paper ribbon and it was possible to set a relative position between the primary and secondary type wheel. Also, a type wheel with letters that could be rearranged became available. The later CX-52 model has 6 pinwheels with 47 pins each and a more flexible pinwheel advancing system as the C-52, resulting in a complex and higly irregular wheel movement.

Instead of developing a version with fixed keyboard like the BC-543 machine, the C-52 could be fitted with a separate keyboard attachment, called B-52 which included the electric motor to drive the drum of the C-52. The configuration with keyboard was designated BC-52. The very popular C-52, CX-52 and BC-52 were sold all over the world. More technical details on the 52 model on this page. You can download a BC-52 simulator on this page.

The CX-52 RT has a tape reader to use of one-time tapes. Another development, based on the 52 series was the PEB machine designed to make enciphering easier for telex traffic. This was a combination of an adapted BC-52 model, called BC-621, connected to the PEB-61 tape punch and reader.

Image  D Rijmenants 2009

Hagelin CX-52

The Pocket Machines

On demand of the French Gendarmerie, a small pocket device was developed with the name CD-55. Two years later, the CD-57 was manufactured. Input and output consisted of a ring with an alphabet and a rotatable disk inside. The alphabet was displaced by pressing a levergrip with the thumb. The displacement depended on the setup of 6 small pin-wheels, similar to those used in the C Type machines. About 12,000 of these pocket models were sold to different countries. The CD-57 RT is has an option to use one-time tapes (random five bit punched tapes).

Hagelin goes On-line

After abandoning the TMX all-in-one Ciphering Teleprinter prototype, Hagelin decided in 1948 to develop the Telecrypto Machine, an on-line crypto device, connected between a standard teleprinter and the line, which could encipher and decipher the telex signals in real-time.

Image  John Alexander

Hagelin CD-57

The first machine was designated T-52 and had 6 fixed pin-wheels and a drum with 2 x 12 slide-bars, similar to the C-36 model. The T-52 was produced in series between 1953 and 1954. Its successor, the T-55 used 6 interchangeable pin-wheels and a drum with 22 slide-bars, similar to the C-52 series. The T-55 had a tape reader that could be used to perform a superencipherment. This was a combination of the normal enciphering with a random one-time-tape. The T-55 was in production until 1956.

Prototypes and rare models

Hagelin did research on various types of mechanical encryptions and developed several different prototypes. One special version of the C Machine was the C-36 with Autokey, which had a second drum, connected via gears to the indicating disk. The device never came into production because of the problems, inherent to the Autokey system, to recover the message when an error during transmission occurred.

The TMX-53 was a ciphering teleprinter but its development was stopped as Crypto AG could not compete with major teleprinter firms. Instead, Crypto AG focused on the Telecrypto Machine which could be connected to standard teleprinter machines.

An advanced electromechanical cipher machine was developed and designated HX-63. The HX-63 had 9 rotors with 41 circuits of which the surplus wires were looped back on the outside (somewhat similar to the KL-7 ADONIS). All circuits could be rearranged and the rotors performed irregular movements like the C-52 series. All this provided an incredible key space of 10600. Manufacture of the HX-63 was abandoned due to the development of fully electronic cipher machines.

The CBI-53 was a random number generator with a printer, which used 40 type wheels and mixing chambers which held 26 steel balls of which one ball was a bit larger than the other 25 balls. After mixing, the balls were run into a tube until the thick ball blocked the tube. The number of balls in the tube was measured and determined the rotation of the type wheel.

After the transition from mechanical and electromechanical cipher machines to fully electronic machines, Crypto AG kept playing a leading role in the development of new crypto systems such as the H-4605, HC-520, and more recently the SECOS radio series, MULTICOM radio encryption, encrypted satellite lines and many IT solutions.

Image  John Alexander

Hagelin HX-63

More Hagelin Machines

Image  John Alexander

BC-38 (predecessor of BC-543)

Image  John Alexander

C-446A (M-209 spinn-off)

Image  John Alexander

CX-52 with Punch Tape Reader

Image  John Alexander

CX-EPX-1 Experimental Machine

Image  John Alexander

H-4606 Off-Line System

Image  John Alexander

H-4606 Open

Image  John Alexander

HX-63 with its cover removed

Image  John Alexander



Pictures Courtesy John Alexander, Leicester and Willy Geiselmann

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Boris Hagelin, The Story of Hagelin Cryptos.

Copyright 2004 - 2016 Dirk Rijmenants

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