Spy radio
Burst encoders
• • • Donate • • •
   Logo (click for homepage)
BBC Vericrypt 1100
Time-division speech scrambler SV12

Vericrypt 1100 was a time-division speech scrambling device, developed by Brown Boveri and Company (BBC) in Switzerland around 1980 as the successor to the Cryptophon 1100 with which it was compatible [3]. It was intended for use with narrow band VHF/UHF 2-way radios and was widely used by Police Forces in Europe in the days before digital encryption became mainstream. It is also known as SV12-1101 and by its military designator NSN 5810-12-188-5670.
The Vericrypt 1100 series can be seen as the miniaturised version of the Cryptophon 1100 series, that was released six years earlier. Unlike the Cryptophon, where the daily key was set by means of six thumbwheels hidden behind a flap, the encryption keys of the Vericrypt had to be entered by means of an external key loader.

The image on the right shows a typical Vericypt 1100 unit [1] with the proprietary Vericrypt key loader [2] connected to the LEMO socket at the front panel. The keypad on the key loader is used to enter the 6 digits of the crypto key.
Verycrypt 1100 in mobile carrier with key loader connected. Devices donated by [1] and [2]. Many thanks!

Once the key is entered, it is stored inside a Static RAM chip and retained by a small lithium battery so that it does not get lost when power is cut-off. Like the Cryptophon, the Vericrypt also has an internal or basic key, which is fixed in a PROM. Is is currently unknown how it is changed.
Although the Vericrypt unit above has nearly the same dimemensions as the older Cryptophon, the actual crypto module itself is much smaller. At the heart of the device, behind the lockable door, is a removable unit that has the same size and shape of an average portable police radio.

It can be removed by pulling-out a knob to the right of the door. At the rear of the crypto heart is a 25-way male plug that mates with a female socket inside the unit. The image on the right shows how the crypto unit is installed again. The door should be locked to keep it in place.
Inserting the crypto unit

The configuration shown above was used for mobile applications, such as in a police car or a military vehicle. As the unit shown here is green, it was probably used by the Army or the Border Patrol. The green case merely acts as a carrier for the actual 1101 crypto unit. It houses quite a bit of additional electronics though, which allows it to be connected to a telephone line as well.
There was another version of the carrier that had a socket for the connection of a handset, to the right of the lockable door, together with a switch and an indicator light. That version was used for legacy installations in existing (police) cars.

Unlike the older Cryptophon, the Vericrypt was suitable for portable applications as well. By adding a small adapter to the bare crypto unit, the device was converted to a portable unit, that was roughly the same size as a conventional handheld radio. The image on the right shows the unit with the portable adapter installed.
Vericrypt 1100 portable version

The portable adapter has a small rotary selector on its front panel, probably for the selection of the key, plus two leads with connectors at the end: a short one and a longer one. The female connector was for connection of the handset, whilst the male connected mated with the handset socket of the radio. In other words: the unit was inserted between the handset and the radio.

When using the Vericrypt, the user has to be aware of a 0.5 second delay in the audio path. This is a feature of the time-domain scrambling that is used here. The Vericrypt 1100 could also be used on telephone networks, although it does not have echo cancellation on 2-wire networks [2]. The unit shown here was used for many years by a crime unit of the Dutch police, who used it in a number of high-profile cases. Note however, that this type of encryption is inherently unsafe.
Vericrypt1100 Vericript 1100 with key loader connected Vericrypt 1101 crypto module Vericrypt 1101 front panel Opening the door Removing the crypto unit (pull the plug) Inserting the crypto unit Removing the crypto unit
Portable adapter Vericrypt 1101 and the portable adapter Vericrypt 1100 portable version Embedded 25-way sub-D male connector 1101 encryption module on top of the slot Vericrypt 1100 key loader Front panel (door closed) Front panel (door open)

Between 1978 and 1981, the Cryptophon 1100 and Vericrypt 1100 were tested by a number of West-German agencies, such as the police, the Ministry of Internal Affairs and the German Intelligence Agency (BND). They considered the system safe and between 1981 and 1982, a large number of Cryptophon and Vericrypt 1100 units were installed with the various agencies.

In 1983 the East-German cipher bureau managed to break the cipher by reconstructing the keys from a series of intercepts. They also built their own equivalent of the Cryptophon, known as the A-003, that was used in the breaks. Another device, the so-called A-004, was used to decipher the Vericrypt 1100. As a result, they managed to read about 90% of the West-German Cryptophon 1100 and Vericrypt 1100-based radio traffic during the 2nd quarter of 1988 [4].
The actual voice scrambler itself is housed in a slimline die-cast aluminium case that consists of two shells. It can be opened by removing four bolts (two at either side), after which the shells can be removed. The two end panels have rubber gaskets and the frontpanel can be removed easily.
The interior consists of two printed circuit boards (PCBs) that are mounted together as a sandwich. One PCB, the digital board, acts as the carrier to which the rear panel (i.e. the 25-way male sub-D connector) is fitted. The other board contains the analogue electronics. The boards are connected together by means of a long row of pins along one of the long sides (blue strip).

The analogue board is held in place by four bolts at the corners. After removing these bolts, the board can be taken out, as shown in the image on the right. It contains the main oscillator.
Two PCBs separated

The digital board is densely populated and hold a number of components that are marked with OEM numbers. Nevertheless, we can make a few 'educated guesses'. At the bottom left is the main processor (the white LN1091E) with a PROM or masked-ROM just above it (LN1281E).
To the right of the processor are two Harris HM1-6504 CMOS RAM chips that can hold 4096 bits each. These RAMs are used to hold the 6-digit cryptographic keys. They are retained by a small lithium battery that is installed in a fitting at the top right (the battery is not installed here).

The big white chip marked LN1171 at the top edge of the board, is an IO-expander. It forms the bridge to the analogue board. The 25-way sub-D connector at the left is the bridge to the outside world (i.e. the carrier). At the right is the front panel that is fitted onto a 6-pin connector.
Digital board (top view)

The analogue board is clearly the more complex one. It consists of various layers of components that are cleverly mounted on top of each other in order to save space. It contains the same analogue electronics as its predecessor, the Cryptophon 1100, albeit in a much smaller space.
Looking at the board from one of its sides shows us that there are three layers of components. All conventional components (resistors, capacitors, diodes, ICs, etc.) are mounted directly onto the PCB, whilst a number of sub-circuits are present in the form of hybrid modules. These are the bright brown and green coloured rectangles.

A hybrid circuit generally consists of a ceramic carrier with SMD 1 components on it. Note that the brown rectangle at the right actually consists of two stacked hybrid circuits, each soldered to the board by means of a single row of pins.
Analogue board (top view)

Also note that between the green hybrid and the board are two further white hybrids. Another white hybrid is located under the brown one at the top left. At the bottom (along one of the longer sides) is a row of 32 pins by which the analogue board is connected to the digital one.
The central oscillator is located at the bottom right corner of the analogue board. It contains a 4.1666 MHz crystal that produces a 240 µs clock for both the analogue and the digital circuits.

For mobile and desktop applications, the crypto unit is usually mounted inside the wide case that is shown at the top of this page. Apart from acting as a carrier for the crypto unit, this case contains some additional electronic circuits to make it suitable for the radio to which it is connected or, as in this case, to adapt the audio signals for connection to a PSTN telephone line.
Electronics inside the Vericrypt 1100 mobile carrier

In the same vein, the small portable adapter, that can be inserted directly into the main Vericrypt 1101 crypto unit, contains a small electronic circuit that adapts the audio levels of the crypto unit to those of the handheld radio to which it is connected, and to the handset of that radio.
  1. SMD = Surface Mounted Device.

Opening the case 1101 crypto module interior Sandwich Two PCBs separated Digital board Analogue board Digital board (top view) Analogue board (top view)
Side view Hybrid circuit Hybrid circuit Processor detail Backup battery holder Front panel (inside) with battery holder on the left Oscillator detail Fitting the front panel

The cryptographic principle used in the Cryptophon 1100 and the Vericrypt 1100, is of the time-division speech scrambler type. Speech is recorded (sampled) and divided over the time domain (scrambling). The simplified diagram below, shows how this works. Speech is cut into small time segments of 30 ms each, and is scrambled with other time segments in an ever changing order. The order in which the packets are scrambled is determined by a pseudo random number generator, or PRNG, that is seeded the cryptographic key that is set with the external key loader.

In this diagram, the top row shows the clear speech (input) in time. The second row shows the speech after it is scrambled. Finally, the bottom row shows the speech once it is descrambled again (output). The process of scrambling and descrambling, causes a delay of approx. 0.5 sec.

As the time segments are scrambled in an ever changing pattern, it is important that transmitter and receiver are correctly synchronised. To ensure that both ends are kept 'in sync', a pilot signal (FSK) is transmitted with the scrambled speech.
Block diagram
Below is the blockdiagram of the Vericrypt 1100. The audio input is at the top left. In transmission mode, audio is filtered, digitised and stored in a temporary memory buffer. The order in which the samples are read out of the buffer, is determined by the number generator (PRN). The new (scrambled) signal is then converted back to the analogue domain again. In order to allow the receiving end to stay in sync, an FSK signal (pilot) is inserted into the output path.

In receiving mode, the synchronisation signal (pilot) is extracted from the incoming audio signal (top left) and decoded. It is then used by the program register (CPU) to keep the pseudo-random number generator (PRN) in sync, so that the packets are re-assembled in the correct order.
  • SV12-1100
    Mobile carrier
  • SV12-1101
    Vericrypt 1100 scrambler
  • SV12-1102
    Key loader
Help required
We are looking for futher details about the Cryptophon and Vericrypt range of products, such as brochures, system descriptions and service manuals. We are also looking for information about other voice encryption products produced by BBC over the years. If you have any of these available, please contact us.
  1. Klaus Paffenholz, Vericrypt 1100 mobile carier - THANKS !
    Device kindly donated, August 2015.

  2. Anonymous, Vericrypt 1101 voice scrambler and 1102 key loader - THANKS !
    Devices kindly donated, June 2015.

  3. W. Baschlin, Integration of time division speech scrambling
    into police telecommunication networks

    Ores Publications (USA), 1977.

  4. Jörg Drobick, Beschreibung des Cryptophon 1100 BStU176
    Der SAS- und Chiffrierdienst (SCD), German.

Further information

Any links shown in red are currently unavailable. If you like the information on this website, why not make a donation?
Crypto Museum. Last changed: Friday, 16 October 2015 - 10:11 CET.
Click for homepage