Devices exist which, by sending an electrical impulse of ultrasonic frequency through a telephone circuit by tapping, will permit remote surveillance of any office in which a telephone is located by utilizing the telephone microphone as a pick-up. Such eavesdropping may be accomplished without additional wires and is possible even though the handset is in a “hung-up” position.
Below, you will find thousands of pages archived from the FBI on ultrasonic listening devices, wiretapping, violations, and countermeasures.
This post was published on January 29, 2023 7:00 am
The Department of Defense (DoD) has released a set of heavily redacted emails in response…
A Freedom of Information Act (FOIA) response has raised new questions about a widely circulated…
In March 2024, the Department of Defense (DoD) published publicly its Report on the Historical…
In September 2024, a Freedom of Information Act (FOIA) request was filed with NASA seeking…
Background Welcome to the FBI Files on Historical Figures & Groups archive at The Black…
A new release of Department of Defense (DoD) emails obtained through the Freedom of Information…