03-06-2017, 10:34 AM
Yeah it is kinda counter-intuitive. Especially if the person who restores/repairs it is new to tubes and has been dealing mostly with solid state or is learning on the fly. From the solid state the depleted mode FETs are the only ones that use negative bias and their usage since has dwindled.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.