Thermal Emissions Spectrum Analysis® (TESA®)


Minute amounts of heat are generated as electricity moves through surveillance device circuitry. Our laboratory grade TESA® instrumentation senses and displays these temperature differentials... as little as eighteen-thousandths of a degree Celsius!

This eavesdropping detection technique allows us to discover surveillance cameras and bugs hidden in ceilings, walls, and antique furniture - without damaging these items during the inspection process.

Our movie page. See this exciting eavesdropping detection technology in action, case histories, and interviews.

A covert TV camera in a ceiling tile shows up as a bright dot.

The large glowing area reveals the power supply.

The center strip ceiling material is solid 5/8" plaster board.

This is a typical corporate conference room with a speakerphone / teleconferencing system.

The system consists of the large viewing screen; a TV camera to the left; and several table microphones… all apparently inactive.



Using Murray Associates' TESA® we see that only the screen is turned off.

The camera and microphones are alive.

Should the system auto-answer a call, or if it is left secretly connected (to any phone, anywhere) the room becomes bugged!

Turn the system off? Good idea, but if one mike is hotwired - an old spy trick - the room is still bugged.


TESA® is just one the techniques we have developed to enhance the speed, and effectiveness of our surveillance and eavesdropping detection audits.

We sincerely thank our long-term client family for their loyal support. Their serious commitment to information security makes our proprietary technical advances possible.