Reminds me of techniques used to detect CRT radiation to rebuild what is being displayed. <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Van_Eck_phreaking" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Van_Eck_phreaking</a>