The SED™ EL509/6KG6 is a beam power tetrode intended for use in class A, AB or B audio amplifiers and for class B or C RF amplification. Close manufacturing specification tolerances and improved high voltage processing provides improved reliability and superior performance. The SED™ EL509/6KG6 features: Increased peak cathode emission from new cathode materials; Stable operation from extended processing and aging; Gold-plated grid; Precise grid/screen alignment; Extra-heavy glass envelope for ruggedness; Improved vacuum processing; Comprehensive testing before and after aging.
The SED™ EL509/6KG6 is manufactured in Russia at the SED SPb factory and is designed to be a direct replacement for any 6KG6 or EL509

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