YouTube Tutorial: Spying on Computer Monitors with TempestSDR

Over on YouTube SignalsEverywhere (aka Corrosive) has uploaded a tutorial video showing how to use TempestSDR with an Airspy SDR. Back in November 2017 we posted about how we were able to get TempestSDR to run with an RTL-SDR, Airspy and SDRplay, and showed some results. Since then several people have managed to repeat our results, but many have also had trouble understanding how to make TempestSDR work and what all the settings are for.

TempestSDR is an open source tool that allows you to use any SDR that has a supporting ExtIO (such as RTL-SDR, Airspy, SDRplay, HackRF) to receive the unintentional signal radiation from a screen, and turn that signal back into a live image. This can let you view what is on a screen without any physical connections.

Corrosive's tutorial video shows us how to tune the signal in the TempestSDR software in order to receive a clear image as well as showing the software in action.

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Thanks for sharing! Totally awesome work in modern times!

Have you figured out why your images aren’t as clear?

Do you need a more directional antenna focused on the target and maybe a background antenna to subtract out all the other environmental signals versus the target signal like as a hardware, or even a software, pre-processing step before processing through the system?

I’m not sure how the hardware is setup. I’m still reading into this system. Interesting research!


Yeah… you figure unless you have digital signals… they’re pure analog RF signals with some multiplexing and/or modulation I guess in general.

The analog are easier to acquire and decode I’m thinking with commercial off the shelf equipment and not extra software even.

In regards to shielding… think like the system has to be like the super quiet systems build that are more like passive and/or anechoic chamber style… however, more Faraday Cage style using copper braid around all the wires with continuous shielding maybe even considering materials like Mu-Metal depending if shielding from electric or magnetic more-so field leakage.

j hill

nice to someone besides the goverment able to tap into the signals , is this from the video driver card or generated in the monitor it self ? is this a CRT or flat screen ?
have you found each model use’s a different frequency ? find any that do not leak ?

GiamMa-based researchers SDR R&D IoT

the signals are generated by the video card and more precisely by the signal passing in the cable creating an RF / EMI / electromagnetic field. My tests have focused on video cards both NVIDIA and AMD and LCD monitor (also works with CRT) with different resolutions (1280×800, 1280×1024), different physical connections (VGA, DVI, XVGA) and the various combinations (1280×800 xvga, 1280×1024 vga and 1280×1024 dvi). it is not easy to calculate the exact frequency of RF / EMI / electromagnetic (you can see frequaency on video). Depends on many factors, then the frequency of the original vertical and orrizontal signals, then the refresh rate, the cable length and more. These factors then create an interference between the main signal and the other main and related harmonic signals.

GiamMa-based researchers SDR R&D IoT

This is my test:

Test – TempestSDR with RTL SDR on windows – Desktop DVI Monitor

Test – TempestSDR with RTL SDR on windows – Desktop VGA Monitor

Test – TempestSDR with RTL SDR on windows – Laptop Monitor

During my windows tests I encountered various errors and exceptions such as “Exception in thread” AWT-EventQueue-0 “java.lang.UnsatisfiedLinkError:”.

The solution that worked for me was to follow the following tutorial, How to settings MinGW / MinGW C++ Download and Installation:

The version of java to be used must be higher than release 52, with version 8 I have not encountered problems on windows 32 and 64 bit.

My test of Eavesdropping on DELL Laptop Computer Screens via electromagnetic interference (EMI) using rtl sdr on Windows. Monitor Resolution WXGA 1280×800 60hz:

To look for the frequency of interference signal, I recommend searching by scanning one waveform with many subsequent peaks between 300 and 700 Mhz.

After tuning in to the targhet frequency let the software take autocalibriums and try to move a few Mhz to center the targe