DV (CL) type power amplifier circuit

The resistance value of each resistor in the circuit should be selected based on factors such as the quiescent current of each tube . First determine
the ^FE and VBE of each tube . Then select the quiescent current D of each level to select the quiescent current of the output tube based on the two points of reducing crossover distortion and not making the DC
power consumption too large. This can be determined based on the shape of their VBE-LC curve, which is roughly About 20mA
. Determining the quiescent current of push tubes VT7 and VT8 can be done at the same time as selecting RE7 and R. The circuit
is shown in Figure 1-38 . Their resistance is smaller, which is beneficial to work under high frequency conditions and has good thermal stability. A little. But if it is too small, the DC
power consumption of the push tube will increase, and the output power will be affected due to the limitation of saturation voltage drop. Under normal circumstances, the quiescent current of the push tube can be 4 to 50 degrees. The quiescent current of VTs and VT6 Sample selection should be made: first find the working current of Vn and VT8 base at full power output , and then take 3-5 times of this value