Sometimes it is difficult to understand why in a 6-tube radio receiver with a universal power supply unit, which already automatically leads to the idea of its simplification due to the rejection of a power transformer, a sophisticated system of switching from direct current to alternating current is installed using ... an autotransformer )) , and for switching the voltage power supply from 220 volts to 127 volts, it is necessary to change the urdox in the power supply unit to the corresponding voltage value.