4049-C

After shipment the filament must be run at full voltage for 30 minutes, before any anode voltage is applied. This rectifier being directly heated, the output circuit must be connected to the mid-point of the filament transformer. The filament transformer should be so connected that the anode and filament voltages are 90 degrees out of phase. Maximum current should be reduced by 50% if quadrature operation is not possible.