Technical Surveillance Counter-Measures

TSCM (Technical Surveillance Counter-Measures) is the original military abbreviation provided to the trade of bug-sweeping or electronic counter-surveillance. It is related to ELINT, SIGINT and ECM.
The United States Department of Defense defines a TSCM survey as a service provided by qualified personnel to detect the presence of technical surveillance devices and hazards and to identify technical security weaknesses that could aid in the conduct of a technical penetration of the surveyed facility. A TSCM survey will provide a professional evaluation of the facility's technical security posture and normally will consist of a thorough visual, electronic, and physical examination in and about the surveyed facility.
This definition is however lacking some of the technical scope involved. COMSEC (Communications Security), ITSEC (Information Technology Security) and physical security are also a major part of the work in the modern environment. The advent of multimedia devices and remote control technologies allow huge scope for removal of massive amounts of data in very secure environments by the staff employed within, with or without their knowledge. Even PlayStation Portables (PSPs) have wireless connectivity and optional storage capacity. Therefore connection and forward on receive over 54 Mbit/s wireless for hundreds of meters is achievable.

Technology used for a bug sweep includes but is not limited to:

Multimeters for general measurements
Time-domain reflectometer (TDR) for testing integrity of telephone lines and other communication cables
Frequency scanner with a range of antennas and filters for checking the electromagnetic spectrum for signals that should not be there
Oscilloscope for visualisation of signals
Spectrum analyzer and vector signal analyzer for more advanced analysis of signals
Nonlinear junction detector (NLJD) for detection of hidden electronics
Portable x-ray machine for checking the inside of objects and walls.
Computer security devices and tools for computer-related threats
Tools for manual disassembling of objects and walls in order to visually check their content. This is the most important, most laborious, least glamorous and hence most neglected part of a check