Description
The Audio Diode FA10AM-4 is an inline analog security device that enforces unidirectional audio flow between a host PC and connected audio peripherals. It is designed to mitigate eavesdropping and audio-based data exfiltration in sensitive environments. The device allows standard playback to speakers or headphones while preventing reverse audio paths.
Key features include an enforced unidirectional audio path, an integrated low-pass filter, and a manually enabled microphone option. The unidirectional design prevents speakers or headphones from being repurposed as microphones by malicious software. The low-pass filter restricts signals to the human-audible band to block ultrasonic or high-frequency covert channels.
Technically the FA10AM-4 operates as an analog-to-analog diode inline between a source and an audio device. Audio passing through is filtered to the human hearing range to reduce risk from high-frequency attacks. The microphone function is hardware gated and only enabled via the front-panel push-button control, preserving the unidirectional guarantee unless explicitly activated by the user.
Connectivity is simple and compatible with standard analog audio interfaces used in desktop and workstation environments. The device is installed inline between the PC audio output and the speaker or headphone input and is compatible with typical analog audio cabling. No protocol conversion is performed – the unit enforces directionality and filtering at the analog level.
Typical use cases include secure conference rooms, classified workspaces, research labs, and any scenario that requires prevention of audio-based data leaks. The device reduces risk of attackers converting output devices to input devices or of exfiltrating data via ultrasonic channels. It is appropriate where preserving standard audio playback while preventing reverse-channel attacks is required.
The FA10AM-4 is built for straightforward installation and daily use – it installs inline with minimal configuration and uses a push-button to enable the optional microphone only when needed. The passive analog design minimizes dependencies on host drivers or firmware updates. Rugged mechanical design and simple controls make it suitable for deployed secure environments where reliability and predictable behavior are essential.


