It is known that the computer display images can be reconstructed from display's radio frequency emanations. This is a big information leakage threat for information security. Recently published eavesdropping systems are very expensive and not portable. Furthermore all the published eavesdropping attacks are demonstrated for distance up to 10 meters away from display. In this work, a low-cost and all-in-one mobile receiver is combined to capture emanations from long distance approximately 50 meters away from display and to reconstruct the display images. In our eavesdropping scenario, receiver system is in a building and the target display is in another building. These experiments show that 26 points and bigger fonts can be read easily from the reconstructed images which are captured from the target display approximately 50 meters away. With this new system, we can also capture emanations from 3 meters away of the target display in an office environment for comparison. In this latter experiment 9 points and bigger fonts can be read easily.
