Use continued to grow until the 1920s when vacuum tube radios replaced them. IC chips reversed the economics of radio design used with vacuum tube receivers. He built his higher order filters from 2-pole filters separated by vacuum tube amplifiers. However his achievements were overlooked because of the success of vacuum tube technology. The principle of operation is identical to that of a vacuum tube triode. Together they established a vacuum tube laboratory. Cooper had developed an alloy that could be used in the manufacture vacuum tube components. A catastrophic failure is one which suddenly makes the vacuum tube unusable. The dc bias current of vacuum tube V1 also flows through the lamp. His assistant in vacuum tube research was his cousin William Comings White. Other components in vacuum tube circuitry can be damaged by EMP. This type of circuit was used for thermionic valve (vacuum tube) technology. This, in turn, led to the development of the vacuum tube. The Anger camera uses sets of vacuum tube photomultipliers (PMT). This invention was the first vacuum tube.