Figure 16, simplified schematic of Heath and Eico power supplies. Except for tube numbers there are no component values given in this schematic. Rectifier and filters are replaced by battery symbols. There are 3 of them labeled E1, E2, and E g 2. The negative of E1 connects to the negative output terminal of the power supply. The positive of E1 connects to the plate of the pass tube labeled as two 6L6GBs in parallel. The negative of E g 2 connects to the cathode of the pass tube. The positive end of E g 2 connects to the screen grid of the pass tube. The cathode of the pass tube connects to the positive output terminal of the supply. There is a resistor connected from the cathode to the control grid of the pass tube. The positive of E2 connects to the negative of E1. As you remember the negative of E1 connects to the negative output terminal of the power supply. The negative end of E1 connects to the anode of a gas discharge regulator tube, zero eh two. The cathode of the zero eh two connects to the anode of another zero eh two. The cathode of the second zero eh two connects through a resistor to the negative of E2. A small pentode, 6 B H 6 has its cathode connected to the junction of the two V R tubes, zero eh two. This point will be at 150 volts negative with respect to the negative output terminal of the power supply. The positive of E1 connects through a resistor then another resistor to the junction of the two V R tubes. The junction of these two resistors connects to the screen grid of the 6 B H 6. The screen grid also connects through a capacitor to the negative of E1. The suppressor grid of the 6 B H 6 connects to its cathode. The plate of the 6 B H 6 connects to the grid of the pass tube. One end of a pot connected as a rheostat connects to the cathode of the pass tube. This pot is labeled zero volt adjust. The other end of the pot goes through a fixed resistor then to the top of the output voltage pot. The wiper of this pot goes through a resistor to the grid of the 6 B H 6. There is a capacitor connected between the grid of the 6 B H 6 and the cathode of the pass tube. The bottom of the output voltage pot goes through a resistor to one side of another pot connected as a rheostat. This pot is labeled 400 volt adjust. The other end of this pot connects to the cathode of the second zero eh two. This point will be 300 volts negative with respect to the negative output terminal of the power supply. This completes the verbal description.
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