Diver down flag. A diver down flag, or scuba flag, is a flag used on the water to indicate that there is a diver below. Two styles of flag are in use. Internationally, the code flag alfa/alpha, which is white and blue, is used to signal that the vessel has a diver down and other vessels should keep well clear at slow speed.
Familiarize yourself with some friendly network cables and take a closer look at common types of network media, including twisted-pair cable, coaxial cable, fiber-optic cable, and wireless.
Twinax cable. Twin-lead â This type of cable is a flat two-wire line. It is commonly called a 300 Ï line because the line has an impedance of 300 Ï. It is often used as a transmission line between an antenna and a receiver (e.g., TV and radio). These cables are stranded to lower skin effects.