In electronics, the 300B is a directly-heated power triode vacuum tube with a four-pin base, introduced in 1938 by Western Electric to amplify telephone signals. It measures 6.4 inches high and 2.4 inches wide, and the anode can dissipate 40 watts.
The 300B is a type of power triode vacuum tube used in electronics, specifically designed for amplifying telephone signals by Western Electric in 1938. The device has dimensions of 6.4 inches by 2.4 inches and can handle an anode dissipation of 40 watts.