TSCM - Equipment Description
The following is a description of the most commonly used Technical Surveillance Counter Measures (TSCM) equipment employed by most professional TSCM Providers. This list is not all-inclusive, but does provide a general understanding of the breadth of equipment needed to conduct a thorough and effective TSCM inspection.
Please keep in mind that the most important piece of equipment in a TSCM Inspection is not a piece of equipment at all, it is a person, the TSCM Technician. All of the following equipment is practically useless in the hands of someone without the proper training and Practical experience in TSCM inspections.
No one piece of test equipment can locate eavesdropping devices, all they can do is give the TSCM technician a clue where to investigate further. Ultimately the only things that can ever detect an eavesdropping devices are the eyes, ears and hands of an experienced and well educated TSCM technician. When operated properly, this equipment can only tell the TSCM technician where to look, NOT what's located there.
Spectrum Analyzer
A Spectrum Analyzer is the workhorse and a must have in any proper Technical Surveillance Counter Measure (TSCM) analysis. The Spectrum Analyzer is a free air sweep engine that captures transmissions that are traveling through the air. When coupled with a Vector Signal Analyzer a TSCM Technician can detect virtually any Radio Frequency (RF) transmission present within the environment including friendly and hostile transmissions that include AM, FM, SSB, Sub-carrier, Carrier Current, Infra Red, Video Transmissions and Intermittent Digital Transmitters.
Vector Signal Analyzer
A Vector Signal Analyzer (or VSA) is an instrument that provides a more advanced analysis of threatening and friendly RF signals and allows for modulation identification and evaluation of modern digital signals including AM, FM, BPQSK, QSK, and Pulse. Although this instrument is similar to an oscilloscope, the Vector Signal Analyzer also allows the additional analysis of two components (I and Q) of a signal. Modern eavesdropping devices, that utilize vector modulation techniques, typically may only be identified by examining both the I and Q components of an electromagnetic anomaly. This will instrument identify all but the most exotic digital eavesdropping devices
Non-Linear Junction Detector
A quality NLJD provides the capability to detect hidden electronic devices, regardless of whether the device is radiating, hard wired, or even turned on and functioning at all, as its detects the electronic components (typically a semi-conductor) associated with most electronics, including hidden eavesdropping devices.
A Non Linear Junction Detector finds potential eavesdropping devices by flooding a suspect area or target with a spectrally pure microwave RF signal. Various frequencies are then monitored for a reflected harmonic signal indicating a potential device. Any positive indication would be further investigated with a metal detector, X-Ray examination, thermal viewer and/or a physical inspection to confirm the actual presence or absence of an eavesdropping device.
When Hollywood wants to portray a “bug sweep” (TSCM survey) in a movie or TV show, the NLJD is typically the device that they will have the actor use. The actor will be shown holding the a device that looks somewhat like a metal detector on a boom, slowly walking and waving the end of the device over furniture and walls, while listening on a set of headphones.
An NLJD can help to detect:
Active or Live Bugs
Inactive Bugs
Turned On, Turned Off, and Burned Out
Covert or Concealed Video Cameras
Microwave Transmitters
Remote Control or Remote Powered Bugs
Resonant Cavity Devices
Concealed Cellular, PCS, and GSM Telephones
Wireless Microphones
Hidden Tape Recorders (even broken ones)
Covert Eavesdropping Devices
Multimeter
A basic instrument for TSCM that is used for the general measurement of power supplies and device components. The multimeter can measure volts, amps and resistance. Most TSCM professionals will utilize three (3) different multimeters including an Analog Handheld VOM, a Handheld Digital Multimeter and a High Grade Bench-Top Digital Multimeter.
Time Domain Reflectometer
A Time Domain Reflectometer analyzes the integrity of a conductor (wire, cable, or fiber optic) typically used for communications, by sending a pulsed signal into the conductor and then examining the reflection of that pulse. By examining the polarity, amplitude, frequencies and other electrical signatures of the reflections, the TSCM Technician can locate the presence of and the immediate location of eavesdropping devices or other source of tampering. Any device or wire attached to the conductor will cause a detectable anomaly; the TSCM Technician will then perform a physical inspection at the location of the anomaly to determine if an eavesdropping devise is present.
Thermal and Infra-red Imaging Instruments

A Thermal Imager is used by the TSCM Technician to detect areas in the environment with suspicious heat signatures (hot spots) that may indicate anomalies caused by active eavesdropping devices that are generating heat or structural elements, including structural modifications that are used or created to secrete an eavesdropping device, such as a wall acvity.
An Infrared Imager will allow the TSCM Technician to observe Infra-red (IR) blooming commonly emitted by optical eavesdropping devices that may be secretred in the area. These optical eavesdropping devices may include live feed as well as recording cameras. The Infrared Imager is able to identify a spectrum of light that cannot normally be seen with the naked human eye.
Carrier Current Analysis Instruments
A TSCM technician will use various instruments and tools to test the electrical, phone and unused lines to determine if they are used as an egress for intercepted communications.This would include devices like a high gain audio amplifier for testing wiring systems and phone lines, or the new TALAN Telephone and Line Analyzer that provides a complete integrated suite of tools to analyze, inspect, and test digital telephone lines (and other wiring) for taps and other eavesdropping devices.
Portable Digital X-Ray Imaging System
When a suspect area is identified within the environment, some TSCM Technicians will utilize an xray imaging system to take an image of the inside of the wall, package or object in question to determine the existence of any eavesdropping devices. The image can be seen on a computer screen and can either lead to further examination or clearing of the suspect area, without having to mechanically and physically disrupt the area for an indepth physical examination.
Digital Oscilloscopes
This instrument is used for the visualization of signals. Most TSCM professional ls will utilize a hand held digital oscilloscope as well as a high-grade bench-top oscilloscope
Acoustic Leakage Probing Devices
These probing devices are used for the testing and determination of the propensity for information to be lost through acoustic leakage. Typically areas to be tested include water pipes, windows, air ducts, etc.
Physical Inspection Tools
During the physical search the TSCM Technicians will use miscellaneous tools and test sets to assist with locating and identifying eavesdropping devices. This is the most important, most laborious and least glamorous part of a TSCM sweep. During the physical inspection the following tools and devices will typically be used:
Stethoscopes
Physical Probes
Audio Probes
Audio Preamps
Audio Amplifiers.
White Light Flashlights
Directional and Forensic Lighting Sources
Ladders
Handheld inspection mirror
Borescopes (tubular mirrors)
Tools for manual disassembling of objects and walls in order to visually check their contents.