The term balun (pronounced bal-un) is derived from the function of the passive device that converts between a BAL anced and UNbalanced electrical signal. Common types of baluns convert 100 Ohm twisted pair (balanced) to 75 Ohm coaxial (unbalanced).
Commercial Driver License (Class A, B or C) A commercial driver license (CDL) is required for drivers of heavyweight vehicles, 26,001 lbs. or more gross vehicle weight rating (GVWR), vehicles hauling a trailer that is 10,001 lbs.
The type of vehicle you intend to operate dictates your CDL classification, and vice versa. Classes for commercial driver licenses are: Class A. Class B. Class C. Each CDL classification is distinguished by the vehicle's gross vehicle weight rating (GVWR) among other items. Keep in mind that the CDL classification you apply for will determine not only the type of vehicle you are allowed to drive, but also which endorsements you may be required to obtain.