Cathode output tube power amplifier circuit

The figure below uses cathode output mode. Since the power stage has no voltage gain, two stages of voltage amplification are required to meet the requirements. Only one stage of amplifier is drawn in the circuit. It is mainly to reflect the special form of power supply. The circuit has good experimental results, and the first stage of voltage amplification can also output about one watt of power. If a two-stage voltage amplifier is used, negative feedback can be added between the two poles to improve performance. In the circuit, the primary DC resistance of the output transformer should be selected between 27O and 3OOΩ. When using different power tubes, different primary DC resistance values ​​of the output transformer should be selected to meet the requirements of the power tube for cathode resistance. This circuit is not suitable for power tubes with higher gate negative voltage.