ULTRA   LINEAR AUDIO AMPLIFIERSUltra-Linear operation provides a compromise between the high efficiency of tetrodes and the low distortion and uncritical load impedance of triodes.There is an undoubted advantage in modulator service because the matching of the modulator to the RF stage is not so critical and the screen (DC) supply is obtained “automatically” from the transformer.

ULTRA - LINEAR AUDIO AMPLIFIERS
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ULTRA   LINEAR AUDIO AMPLIFIERS