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Bugs
Securitate
  
Securitate bug
Wired room monitoring bug

Securitate bug 1 is a miniature wired covert listening device (bug), developed in the late 1970s, and used during the Cold War by the secret police of the Socialist Republic of Romania — the Securitate — for overhearing conversations in a room. It uses the analogue telephone line as its power supply and for transport of its audio signal. The device shown here, was discovered in the walls of a Romanian institution, several years after the fall of the repressive communist regime.

The image on the right shows the device next to a match. It measures 46 x 9 x 8 mm and weights 6 grams. It is housed in a silver-plated enclosure that consists of two shells. The upper shell has a small hole close to one end, that is protruded by the sound port of a subminiature microphone.

At the other end are three wires 2 by which the device is connected to the telephone line. Two wires are for connection to the A and B wires of an analogue telephone line, whilst the third one should be connected to ground to avoid hum. It is directly soldered to one of the case shells.
  
Covert listening device of the Securitate. Kindly donated by Silviu Groza [1].

The device itself could be hidden inside the wall socket of the telephone, or behind a plastered wall, in such a way that the microphone was able to pick up any sound in the room. The highly sensitive subminiature microphone was made by US manufacturer Knowles, and is also found in hearing aids of the era. Ironically, the development of these microphones had been funded for many years by the US Central Intelligence Agency (CIA), especially for use inside American bugs.

It is currently unknown where the bug was manufactured, but it is likely that it was made in a former Eastern Bloc country, such as Bulgaria, Hungary, East Germany (DDR) or Romania itself, despite the fact that it is entirely made with Western components. The device shows similarity to contemporary bugs, like Bodil (Bulgaria), Botond (Hungary) and 33014 (East Germany), but is far less sophisticated. If you have additional information about this kind of bugs, please contact us.

  1. As the offical name and/or designator of this bug is currently unknown, we have nicknamed it 'Securitate', after the repressive Cold War secret police agency of Romania, who alledgedly exploited it.
  2. Originally there were two black wires and a white one, but these were worn out, and were replaced by black, yellow and blue wires as part of the restoration by Crypto Museum in May 2020.

Securitate wired bug Wired bug used by the Securitate Securitate wired miniature covert listening device Close-up of the Securitate bug Microphone port protruding the upper case shell Securitate bug compared to the size of a hand Interior of the Securitate bug compared to the size of a hand Securitate bug (left) aside Bodil (Bulgaria) and 33014 (DDR)
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Securitate wired bug
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Wired bug used by the Securitate
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Securitate wired miniature covert listening device
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Close-up of the Securitate bug
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Microphone port protruding the upper case shell
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Securitate bug compared to the size of a hand
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Interior of the Securitate bug compared to the size of a hand
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Securitate bug (left) aside Bodil (Bulgaria) and 33014 (DDR)

Features
The diagram below shows the properties of the device. It is housed in a silver-plated brass case that consists of two halves, held together by a piece of cellotape. The device has no controls and is enabled by supplying 48V DC to the blue and yellow wires, typically from a free telephone line.


Inside the device is a two-stage audio amplifier, of which the output is fed back to the telephone line. This signal was then picked up by a Securitate listening post near the telephone exchange. This is illustrated in the diagram below. As soon as the subscriber line is occupied — the user has lifted the handset from the cradle (off-hook) — the line voltage drops and the device is disabled.


This system has several advantages. The device does not interfere with a regular telephone call — it is disabled — and can therefore not be discovered accidentally. Furthermore, room audio and telephone conversations could be recorded at the listening post without additional means.


History
During the Cold War, Romania was a communist country under strong influence of the Soviet Union (USSR). Like the other countries of the Eastern Block, it had a repressive secret police agency that spied on its citizens. It was known as the Securitate and was omni-present [2].

The history of the Securitate dates back to the beginning of the Cold War. It was founded on 30 August 1948, with help from the Soviet Ministry of Internal Affairs (MVD). 1 It was initially known as the General Directorate for the Security of the People (DGSP), and later also as Departamentul Securităţii Statului (DSS), but it was generally known by the public as Securitate. At its height, it had 11,000 agents and 500,000 informers on a population of 22 million [2]. Under the regime of Nicolae Ceauşescu, the Securitate was one of the most brutal secret police forces in the world.

The Securitate was responsible for the arrests, torture and deaths of thousands of people. Like its sister organisations in other East European countries, such as the Stasi (DDR), the StB (Czecho­slovakia) and ÁVH (Hungaria), it kept files on dissidents, placed them under surveillance and tapped their telephone lines. The latter was the responsibility of General Directorate for Technical Operations, that had been established in 1954 with help from the Soviet intelligence services.

In the late 1970s or early 1980s, the device featured here, was planted by the Securitate in the one of the walls of an unnamed Romanian institution, where it was connected to the (analogue) telephone line. It was not intended for tapping the telephone line — that could be done in the exchange anyway — but for overhearing conversations in the room. It was powered by the DC voltage that was present on the telephone line, and delivered its audio signal to the Securitate listening post via the same line. At least two of these bugs were planted in the institution.

  1. Until 1946 known as NKVD. Forerunner of the KGB.

Discovery
After the revolution of December 1989 – that led to the end of the Socialist Republic of Romania – many of the state-owned institutions were privatised, but only very few eventually managed to survive. Between 1997 and 2000 — in the days before mobile phones became mainstream — a person working at the forementioned institution asked a friend to make a device for recording telephone conversions, as there were regular disputes about instructions that had been given.

The friend came up with a simple solution in which he used a portable voice actuated dictation machine (voice recorder) of which the external microphone input was connected directly to the telephone line by means of a separation transformer. It did not require any modification of the telephone set, and would automatically start recording when it picked up an audio signal (voice).


A few days after the installation, the dictation machine appeared to record not only the telephone conversations, but any conversation in the room. Initially it was thought that perhaps the internal microphone of the recorder had not been disconnected properly, but after the microphone was removed completely, it appeared that it still recorded all conversations in the room, and not just the telephone calls. It then began to dawn that perhaps there was a hidden 'bug' in the room.


After following the telephone cables and cutting through several brick walls, the bug was finally discovered and removed from the telephone line. It made the personnel of the institution pretty nervous, and gave them the impression that everything they said was being overheard. People started whispering and turned up the volume of the radio when serious matters were discussed.

Further investigation revealed that there was one more bug in the building: in the office of the general manager. Rather than removing that bug from the plastered wall, the line was simply cut at both ends, and replaced by a new one. The affected institution no longer exists today [3].

Origin
It is currently unknown which company or country produced the bug, but it is likely that it was made by, or on behalf of, the Securitate itself, or at least by a sister organisation from one of the former Eastern Block countries, despite the fact that it is entirely built with Western components.

The miniature resistors and the ceramic capacitors are all made by Philips, whilst the electret microphone is from the American manufacturer Knowles. The two miniature BC123 transistors were made by Siemens in Germany, and the remaining components were made by various other Western manufacturers. None of the parts are made in Eastern Europe. The big capacitor on the top surface of the PCB, gives us a clue when the bug may have been manufactured. As its date code is 08 78 (week 8 of 1978), it was made after this date, probably late 1978 or early 1979.

There are various reasons why the device does not contain any East European parts: (1) miniature parts were not available in Eastern Europe at the time, or were hard to obtain, (2) to hide the true origin of the device, and (3) to blame Western intelligence agencies when it was discovered.

Donation
The device first appeared on a Romanian internet forum in February 2020, where it was described by the person who alledgedly found it in the walls of the forementioned (undisclosed) institution. He also offered it for sale. The story above is largely based on his description on the forum [3].

The device was eventually purchased by a forum participant – Silviu Groza – who sub­sequently donated it to Crypto Museum in May 2020 [1]. We are most grateful for this, as it is one of the rare ocassions in which not only the device has survived, but also some of its history. It is also unique in the sense that it is the first covert listening device (bug) that we have come across, that transmits a plain audio signal over a regular telephone line, without using subcarrier modulation.


Countermeasures
The Securitate bug is a simple yet very effective device. When installed properly, it will be very difficult to discover it. As it is disabled auto­matically when the telephone line is occupied, it will not be noticed by the calling participants.

The only way to discover it on a (suspicuous) telephone line (apart from a visual inspection of the line), is to connect an audio amplifier in parallel (which was how this bug was found) or by using a non-linear wire-line bug detector, such as the Orchidea-2 shown on the right.

 More information

  
Orchidea-2 main unit




Click to see more

Interior
The device is housed in a silver-plated metal enclosure that measures just 46 × 9 × 8 mm. It consists of two high precision manufactured shells, that fit tightly together. Judging from the discolouration of the silver-plated body, the two halves were previously held together by a piece of cellotape, which might have been removed by the finder after its discovery in the late 1990s.

Inside the enclosure is a double-sided epoxy-based printed circuit board (PCB), that measures 42 x 7 mm and has components on both sides. At one end are the wires to the telephone line. At the other end is a Knowles miniature electret microphone, embedded in a cutout of the PCB.

All of the electronic components are made by by Western manufacturers: the microphone is from Knowles (USA), resistors and ceramic capacitors are from Philips (Netherlands) and the miniature transistors are made by Siemens (Germany). The rest was made by various Western companies.
  
Interior -- bottom side

It is possible that suitable miniature parts were not available from local manufacturers at the time, but it is also possible that Western parts were chosen deliberately to hide the true origin of the device. The image above shows the bottom side of the PCB, with a large black 1N... rectifier diode at the center. The two miniature BC123 transistors are to the left and in front of this diode.

Securitate bug after removing the upper case shell Securitate bug after removing both use shells Bare PCB of the Securitate bug Interior -- top side Interior -- bottom side Bottom side of the Securitate bug Seen from the side Miniature transistior
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Securitate bug after removing the upper case shell
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Securitate bug after removing both use shells
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Bare PCB of the Securitate bug
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Interior -- top side
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Bottom side of the Securitate bug
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Seen from the side
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Miniature transistior

Circuit diagram
Below is the circuit diagram of the device, which is built around two BC123 miniature low-noise LF transistors, introduced by the German manufacturer Siemens in 1970 [A]. They were made especially for use in miniature electronic devices like hearing aids. At the far left is the electret microphone, made by US manufacturer Knowles. The signal from the microphone is amplified in the 2-stage audio amplifier (2 x BC123), and is then injected back into the telephone line.


At the far right are the (a) and (b) wires from the telephone line. The device is polarity-sensitive, and has to be connected the right way around. The 20V zener diode protects the second BC123 when the phone rings (60-100V AC). The function of the 0.66µF capacitor is to short out the 22k resistor for AC signals (audio). In this configuration, T2 acts as a current source. The two 1µF capacitors – that were clearly added later – deliver the audio directly back to the telephone line.

The device is powered by the 48V DC voltage 1 that is present on a line when it is in rest (i.e. when the handset is on-hook). As soon as the handset is picked up, this voltage drops to 6-10V DC and the device is disabled. This ensures that the subscribers will not accidentally overhear the audio signal from the bug during a telephone call. The circuit is far less sophisticated than that of contemporary line-carrier bugs, such as the East German 33014 and the Bulgarian Bodil, which used subcarrier modulation to hide the bug's audio signal, and were extremely difficult to detect. However, that fact that it was not discovered until 2000, proves that it was just as effective.

 See how the East-German Stasi used bugs over telephone lines

  1. The exact DC voltage on an unoccupied (analogue) telephones line differs per country and sometimes even per exchange. It was commonly between 30 and 60V DC.

Restoration
When we received the bug featured on this page, the wiring was about to break. The isolation of the wires had become stiff over time, and the solder joints at the cable-end of the device were about to separate, probably due to frequent handling in the years after the bug was discovered. It was therefore decided to replace the wires with modern pliant ones. The white wire was replaced by a yellow one, black became blue, and a black wire was soldered to the case shell (ground).


After connecting the device to a simulated telephone line, using the above circuit, it appeared to be in full working condition. The microphone is very sensitive and the (external) audio amplifier produces a clear high-fidelity audio signal, with very good legibility, without replacing any parts.


Documentation
  1. BC123 low-noise LF transistor 45V/75mA, datasheet
    Siemens, 1972/73.  Alternative datasheet 1970/71
References
  1. Silviu Groza, Original Securitate bug - THANKS !
    Received May 2020.

  2. Wikipedia, Securitate
    Retrieved May 2020.

  3. User Ovidanie (YO8TPP), How the bug was discovered
    ELFORUM - Formul Electronistilor, 28 February 2020.
Further information
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Crypto Museum. Created: Saturday 02 May 2020. Last changed: Saturday, 09 May 2020 - 05:48 CET.
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