re tempest whughes lonestar utsa edu william w hughes writes hell just set up a spark jammer or some other very electrically noisy device this doesn t work due to the near field far field effect you may stop someone five yards away from listening in but someone fifty yards away will be relatively unaffected unless you pump out hundreds of watts and jam all the neighbourhood tv s as well in that case the government will stomp on you ask any radio ham democratic governments care even more about their voters right to watch soap operas than they do about national security and dictators consider their propaganda to be an integral part of their national security and holland cs colostate edu doug holland writes another idea use a laptop computer as mentioned earlier the lcd screen is a lot less noisy than a standard crt but since many laptops have power supplies that run at volts instead of they would be considerably quieter i m afraid this doesn t work either we can pick up laptop screens without any problem most of the so called low radiation monitors are also useless the description turns out to a marketing assertion rather than an engineering one we thought there might be a market for a monitor which was not as hugely expensive as the military tempest kit but which was well enough shielded to stop eavesdropping using available receivers we built a prototype it works and it s still sitting on my lab bench commercial interest was exactly zero in the absence of open standards a monitor which really is low radiation and costs dollars more can t compete against a monitor which just claims to be low radiation and whose only extra cost of production is the pretty blue sticker on the box ross
