If you use those plastic insulation troughs and overlap the top one of the lower ones even if rain should sneak up past the shingles, past the builders felt it will fall on the plastic trough and be carried out past the building envelope.. 1  Reply. 2  Reply to Original. 3  Print this page. 4  Email this Message.
Double-sideband suppressed-carrier transmission. Double-sideband suppressed-carrier transmission (DSB-SC) is transmission in which frequencies produced by amplitude modulation (AM) are symmetrically spaced above and below the carrier frequency and the carrier level is reduced to the lowest practical level, ideally being completely suppressed.
SOS signal. SOS (Save Our Souls) is the best known international distress signal. Everyone should be familiar with SOS. The SOS signal can be transmitted by any method, visual or audio. The code for SOS is 3 short, 3 long and 3 short signals. Pause. Repeat the signal. The SOS signal can, for instance, be constructed as a ground to air signal with rocks and logs, or whatever material you have available. At night you can use a flashlight or a strobe light to send an SOS to, for instance, an aircraft.