Developed by the designers while in Government service, Bloodhound is a fully portable acoustically stimulated microphone detection system.
Its use should be planned in concert with the rest of the Technical Security Inspector’s equipment to maximize the Inspector’s chances of discovering a technical attack, and minimizing the chances of alerting the eavesdropper’s listening post, which may allow the eavesdropper to instigate effective countermeasures. Capability

Bloodhound can be used to detect the following types of espionage attack:

• Primary:

– Amplified wired microphone system where the target site is wired directly to a listening post.
– Audio attack on telephone instruments.
– Audio presence on cables.

• Secondary:

– Radio Microphones – audio component.
– Tape recorder attacks (many types).
– Video camera surveillance (many types).
– General purpose amplification, especially on very weak and noisy signals.
– Cable tracing. Operating Features:

BloodHound can be used in Two modes, Covert (Passive) and Overt (Active)

A typical operation may use either passive, active, or both, depending upon the perceived threat and target environment.

• Covert Mode (Passive):

In this mode the operator uses the filter and headset units to listen for room noises as detected by the eavesdropping microphone.

Advantages:
1. A properly conducted Covert search can be carried out in an environment with staff present and will not alert the listening post.
2. Less prone to false responses than Active mode.

Disadvantages:
1. Takes longer to do properly than active mode.
2. A little less sensitive than active mode.

• Overt Mode (Active):

In this mode the power amplifier is added to the system. If the probe detects a microphone the system goes into acoustic feedback and a characteristic howl is produced.

Advantages:
1. Active mode is the easiest to use mode of operation.
2. Quicker than passive mode.
3. More sensitive than passive mode.

Disadvantages::
1. The high sound level produced can alert the listening post that a sweep is in progress.
2. The high sound level prevents use in a normal office environment with normal staff present.
3. More prone to false responses than Passive mode. System Components
♦ Probe and Antenna
♦ Belt-worn Filter
♦ Headset
♦ Power Amplifier
♦ Sound Source
♦ Robust Transit Case

Материалът BloodHound- microphone detection system е публикуван за пръв път на Profisec.